<informationTable xmlns="http://www.sec.gov/edgar/document/thirteenf/informationtable">		<infoTable>
			<nameOfIssuer>ACCESS MIDSTREAM PARTNERS L</nameOfIssuer>
			<titleOfClass>UNIT</titleOfClass>
			<cusip>00434L109</cusip>
			<value>476955</value>
			<shrsOrPrnAmt>
				<sshPrnamt>9999051</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>9437837</Sole>
				<Shared>0</Shared>
				<None>561214</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ANADARKO PETE CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>032511107</cusip>
			<value>27585</value>
			<shrsOrPrnAmt>
				<sshPrnamt>321018</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>321018</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>APACHE CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>037411105</cusip>
			<value>17087</value>
			<shrsOrPrnAmt>
				<sshPrnamt>203825</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>203825</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BAKER HUGHES INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>057224107</cusip>
			<value>1</value>
			<shrsOrPrnAmt>
				<sshPrnamt>24</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>24</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BOARDWALK PIPELINE PARTNERS</nameOfIssuer>
			<titleOfClass>UT LTD PARTNER</titleOfClass>
			<cusip>096627104</cusip>
			<value>241501</value>
			<shrsOrPrnAmt>
				<sshPrnamt>7996712</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>7996712</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BP PLC</nameOfIssuer>
			<titleOfClass>SPONSORED ADR</titleOfClass>
			<cusip>055622104</cusip>
			<value>10961</value>
			<shrsOrPrnAmt>
				<sshPrnamt>262600</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>262600</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BREITBURN ENERGY PARTNERS LP</nameOfIssuer>
			<titleOfClass>COM UT LTD PTN</titleOfClass>
			<cusip>106776107</cusip>
			<value>12674</value>
			<shrsOrPrnAmt>
				<sshPrnamt>694488</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>694488</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BUCKEYE PARTNERS L P</nameOfIssuer>
			<titleOfClass>UNIT LTD PARTN</titleOfClass>
			<cusip>118230101</cusip>
			<value>552286</value>
			<shrsOrPrnAmt>
				<sshPrnamt>7871806</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>7396437</Sole>
				<Shared>0</Shared>
				<None>475369</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CABOT OIL &amp; GAS CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>127097103</cusip>
			<value>17262</value>
			<shrsOrPrnAmt>
				<sshPrnamt>243055</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>243055</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CAMERON INTERNATIONAL CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>13342B105</cusip>
			<value>2</value>
			<shrsOrPrnAmt>
				<sshPrnamt>33</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>33</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CANADIAN NAT RES LTD</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>136385101</cusip>
			<value>5404</value>
			<shrsOrPrnAmt>
				<sshPrnamt>191240</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>191240</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CARRIZO OIL &amp; GAS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>144577103</cusip>
			<value>82</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2880</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>2880</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CENOVUS ENERGY INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>15135U109</cusip>
			<value>3756</value>
			<shrsOrPrnAmt>
				<sshPrnamt>131690</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>131690</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CENTERPOINT ENERGY INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>15189T107</cusip>
			<value>71953</value>
			<shrsOrPrnAmt>
				<sshPrnamt>3063126</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>3063126</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CHESAPEAKE ENERGY CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>165167107</cusip>
			<value>11982</value>
			<shrsOrPrnAmt>
				<sshPrnamt>587916</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>587916</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CHEVRON CORP NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>166764100</cusip>
			<value>9766</value>
			<shrsOrPrnAmt>
				<sshPrnamt>82523</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>82523</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CIMAREX ENERGY CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>171798101</cusip>
			<value>106</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1625</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1625</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CMS ENERGY CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>125896100</cusip>
			<value>1</value>
			<shrsOrPrnAmt>
				<sshPrnamt>20</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>20</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CONCHO RES INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>20605P101</cusip>
			<value>6834</value>
			<shrsOrPrnAmt>
				<sshPrnamt>81630</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>81630</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CONOCOPHILLIPS</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>20825C104</cusip>
			<value>8393</value>
			<shrsOrPrnAmt>
				<sshPrnamt>138725</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>138725</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CONTINENTAL RESOURCES INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>212015101</cusip>
			<value>20925</value>
			<shrsOrPrnAmt>
				<sshPrnamt>243140</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>243140</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>CRESTWOOD MIDSTREAM PRTNERS</nameOfIssuer>
			<titleOfClass>COM UNITS REPSTG</titleOfClass>
			<cusip>226372100</cusip>
			<value>42360</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1697800</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1697800</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>DCP MIDSTREAM PARTNERS LP</nameOfIssuer>
			<titleOfClass>COM UT LTD PTN</titleOfClass>
			<cusip>23311P100</cusip>
			<value>341471</value>
			<shrsOrPrnAmt>
				<sshPrnamt>6311855</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>6002594</Sole>
				<Shared>0</Shared>
				<None>309261</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>DENBURY RES INC</nameOfIssuer>
			<titleOfClass>COM NEW</titleOfClass>
			<cusip>247916208</cusip>
			<value>1284</value>
			<shrsOrPrnAmt>
				<sshPrnamt>74135</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>74135</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>DEVON ENERGY CORP NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>25179M103</cusip>
			<value>7282</value>
			<shrsOrPrnAmt>
				<sshPrnamt>140355</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>140355</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>DOMINION RES INC VA NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>25746U109</cusip>
			<value>1</value>
			<shrsOrPrnAmt>
				<sshPrnamt>10</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>10</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>EASTMAN CHEM CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>277432100</cusip>
			<value>5</value>
			<shrsOrPrnAmt>
				<sshPrnamt>70</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>70</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>EL PASO PIPELINE PARTNERS L</nameOfIssuer>
			<titleOfClass>COM UNIT LPI</titleOfClass>
			<cusip>283702108</cusip>
			<value>495358</value>
			<shrsOrPrnAmt>
				<sshPrnamt>11343206</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>10770119</Sole>
				<Shared>0</Shared>
				<None>573087</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENBRIDGE ENERGY MANAGEMENT L</nameOfIssuer>
			<titleOfClass>SHS UNITS LLI</titleOfClass>
			<cusip>29250X103</cusip>
			<value>44070</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1455421</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1455421</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENBRIDGE ENERGY PARTNERS L P</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>29250R106</cusip>
			<value>164317</value>
			<shrsOrPrnAmt>
				<sshPrnamt>5389204</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>5389204</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENBRIDGE INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>29250N105</cusip>
			<value>74338</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1767012</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1767012</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENCANA CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>292505104</cusip>
			<value>65</value>
			<shrsOrPrnAmt>
				<sshPrnamt>3855</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>3855</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENERGEN CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>29265N108</cusip>
			<value>103</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1964</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1964</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENERGY TRANSFER EQUITY L P</nameOfIssuer>
			<titleOfClass>COM UT LTD PTN</titleOfClass>
			<cusip>29273V100</cusip>
			<value>423485</value>
			<shrsOrPrnAmt>
				<sshPrnamt>7079329</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>6479817</Sole>
				<Shared>0</Shared>
				<None>599512</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENERGY TRANSFER PRTNRS L P</nameOfIssuer>
			<titleOfClass>UNIT LTD PARTN</titleOfClass>
			<cusip>29273R109</cusip>
			<value>432365</value>
			<shrsOrPrnAmt>
				<sshPrnamt>8554908</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>8326038</Sole>
				<Shared>0</Shared>
				<None>228870</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENERPLUS CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>292766102</cusip>
			<value>4079</value>
			<shrsOrPrnAmt>
				<sshPrnamt>275800</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>275800</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENSCO PLC</nameOfIssuer>
			<titleOfClass>SHS CLASS A</titleOfClass>
			<cusip>G3157S106</cusip>
			<value>3</value>
			<shrsOrPrnAmt>
				<sshPrnamt>49</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>49</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ENTERPRISE PRODS PARTNERS L</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>293792107</cusip>
			<value>922219</value>
			<shrsOrPrnAmt>
				<sshPrnamt>14838603</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>13985111</Sole>
				<Shared>0</Shared>
				<None>853492</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>EOG RES INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>26875P101</cusip>
			<value>28104</value>
			<shrsOrPrnAmt>
				<sshPrnamt>213429</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>213429</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>EQT CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>26884L109</cusip>
			<value>49169</value>
			<shrsOrPrnAmt>
				<sshPrnamt>619495</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>619495</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>EQT MIDSTREAM PARTNERS LP</nameOfIssuer>
			<titleOfClass>UNIT LTD PARTN</titleOfClass>
			<cusip>26885B100</cusip>
			<value>82795</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1694892</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1603697</Sole>
				<Shared>0</Shared>
				<None>91195</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>EV ENERGY PARTNERS LP</nameOfIssuer>
			<titleOfClass>COM UNITS</titleOfClass>
			<cusip>26926V107</cusip>
			<value>5819</value>
			<shrsOrPrnAmt>
				<sshPrnamt>155700</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>155700</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>EXXON MOBIL CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>30231G102</cusip>
			<value>1475</value>
			<shrsOrPrnAmt>
				<sshPrnamt>16329</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>16329</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>FIRSTENERGY CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>337932107</cusip>
			<value>0</value>
			<shrsOrPrnAmt>
				<sshPrnamt>12</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>12</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>GENESIS ENERGY L P</nameOfIssuer>
			<titleOfClass>UNIT LTD PARTN</titleOfClass>
			<cusip>371927104</cusip>
			<value>75783</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1462140</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1351625</Sole>
				<Shared>0</Shared>
				<None>110515</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>HALLIBURTON CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>406216101</cusip>
			<value>3</value>
			<shrsOrPrnAmt>
				<sshPrnamt>79</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>79</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>HESS CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>42809H107</cusip>
			<value>5258</value>
			<shrsOrPrnAmt>
				<sshPrnamt>79076</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>79076</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>HOLLY ENERGY PARTNERS L P</nameOfIssuer>
			<titleOfClass>COM UT LTD PTN</titleOfClass>
			<cusip>435763107</cusip>
			<value>173112</value>
			<shrsOrPrnAmt>
				<sshPrnamt>4550781</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>4417814</Sole>
				<Shared>0</Shared>
				<None>132967</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>HOLLYFRONTIER CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>436106108</cusip>
			<value>1</value>
			<shrsOrPrnAmt>
				<sshPrnamt>34</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>34</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>INERGY MIDSTREAM LP</nameOfIssuer>
			<titleOfClass>U LTD PARTNERS</titleOfClass>
			<cusip>45671U106</cusip>
			<value>70398</value>
			<shrsOrPrnAmt>
				<sshPrnamt>3165387</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>3165387</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>KINDER MORGAN ENERGY PARTNER</nameOfIssuer>
			<titleOfClass>UT LTD PARTNER</titleOfClass>
			<cusip>494550106</cusip>
			<value>345248</value>
			<shrsOrPrnAmt>
				<sshPrnamt>4042719</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>3745720</Sole>
				<Shared>0</Shared>
				<None>296999</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>KINDER MORGAN INC DEL</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>49456B101</cusip>
			<value>98974</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2594343</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>2452849</Sole>
				<Shared>0</Shared>
				<None>141494</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>KINDER MORGAN MANAGEMENT LLC</nameOfIssuer>
			<titleOfClass>SHS</titleOfClass>
			<cusip>49455U100</cusip>
			<value>286118</value>
			<shrsOrPrnAmt>
				<sshPrnamt>3422868</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>3422866</Sole>
				<Shared>0</Shared>
				<None>2</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>LEGACY RESERVES LP</nameOfIssuer>
			<titleOfClass>UNIT LP INT</titleOfClass>
			<cusip>524707304</cusip>
			<value>8540</value>
			<shrsOrPrnAmt>
				<sshPrnamt>321055</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>321055</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>LINN ENERGY LLC</nameOfIssuer>
			<titleOfClass>UNIT LTD LIAB</titleOfClass>
			<cusip>536020100</cusip>
			<value>18462</value>
			<shrsOrPrnAmt>
				<sshPrnamt>556420</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>556420</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>LYONDELLBASELL INDUSTRIES N</nameOfIssuer>
			<titleOfClass>SHS - A -</titleOfClass>
			<cusip>N53745100</cusip>
			<value>6</value>
			<shrsOrPrnAmt>
				<sshPrnamt>89</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>89</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MAGELLAN MIDSTREAM PRTNRS LP</nameOfIssuer>
			<titleOfClass>COM UNIT RP LP</titleOfClass>
			<cusip>559080106</cusip>
			<value>847356</value>
			<shrsOrPrnAmt>
				<sshPrnamt>15547811</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>14557664</Sole>
				<Shared>0</Shared>
				<None>990147</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MARATHON OIL CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>565849106</cusip>
			<value>14513</value>
			<shrsOrPrnAmt>
				<sshPrnamt>419698</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>419698</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MARATHON PETE CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>56585A102</cusip>
			<value>3</value>
			<shrsOrPrnAmt>
				<sshPrnamt>37</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>37</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MARKWEST ENERGY PARTNERS L P</nameOfIssuer>
			<titleOfClass>UNIT LTD PARTN</titleOfClass>
			<cusip>570759100</cusip>
			<value>318815</value>
			<shrsOrPrnAmt>
				<sshPrnamt>4769116</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>4480952</Sole>
				<Shared>0</Shared>
				<None>288164</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MPLX LP</nameOfIssuer>
			<titleOfClass>COM UNIT REP LTD</titleOfClass>
			<cusip>55336V100</cusip>
			<value>170985</value>
			<shrsOrPrnAmt>
				<sshPrnamt>4645063</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>4379046</Sole>
				<Shared>0</Shared>
				<None>266017</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MURPHY OIL CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>626717102</cusip>
			<value>1</value>
			<shrsOrPrnAmt>
				<sshPrnamt>9</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>9</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>NATIONAL FUEL GAS CO N J</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>636180101</cusip>
			<value>26316</value>
			<shrsOrPrnAmt>
				<sshPrnamt>454111</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>454111</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>NATIONAL OILWELL VARCO INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>637071101</cusip>
			<value>0</value>
			<shrsOrPrnAmt>
				<sshPrnamt>7</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>7</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>NEWFIELD EXPL CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>651290108</cusip>
			<value>1440</value>
			<shrsOrPrnAmt>
				<sshPrnamt>60295</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>60295</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>NEXTERA ENERGY INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>65339F101</cusip>
			<value>1</value>
			<shrsOrPrnAmt>
				<sshPrnamt>7</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>7</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>NISOURCE INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>65473P105</cusip>
			<value>66516</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2322498</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>2322498</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>NOBLE CORPORATION BAAR</nameOfIssuer>
			<titleOfClass>NAMEN -AKT</titleOfClass>
			<cusip>H5833N103</cusip>
			<value>3</value>
			<shrsOrPrnAmt>
				<sshPrnamt>85</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>85</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>NOBLE ENERGY INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>655044105</cusip>
			<value>9505</value>
			<shrsOrPrnAmt>
				<sshPrnamt>158305</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>158305</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>NUSTAR ENERGY LP</nameOfIssuer>
			<titleOfClass>UNIT COM</titleOfClass>
			<cusip>67058H102</cusip>
			<value>99407</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2177600</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>2177600</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>OCCIDENTAL PETE CORP DEL</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>674599105</cusip>
			<value>26303</value>
			<shrsOrPrnAmt>
				<sshPrnamt>294783</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>294783</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>OGE ENERGY CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>670837103</cusip>
			<value>12560</value>
			<shrsOrPrnAmt>
				<sshPrnamt>184162</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>184162</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>OIL STS INTL INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>678026105</cusip>
			<value>2</value>
			<shrsOrPrnAmt>
				<sshPrnamt>25</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>25</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>OILTANKING PARTNERS L P</nameOfIssuer>
			<titleOfClass>UNIT LTD</titleOfClass>
			<cusip>678049107</cusip>
			<value>114676</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2257404</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>2120960</Sole>
				<Shared>0</Shared>
				<None>136444</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ONEOK PARTNERS LP</nameOfIssuer>
			<titleOfClass>UNIT LTD PARTN</titleOfClass>
			<cusip>68268N103</cusip>
			<value>152903</value>
			<shrsOrPrnAmt>
				<sshPrnamt>3087705</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>3087705</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ONEOK INC NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>682680103</cusip>
			<value>53295</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1290134</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1290134</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PEMBINA PIPELINE CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>706327103</cusip>
			<value>38875</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1270517</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1270517</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PENN WEST PETE LTD NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>707887105</cusip>
			<value>68</value>
			<shrsOrPrnAmt>
				<sshPrnamt>6400</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>6400</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PHILLIPS 66</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>718546104</cusip>
			<value>3</value>
			<shrsOrPrnAmt>
				<sshPrnamt>47</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>47</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PIONEER NAT RES CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>723787107</cusip>
			<value>31909</value>
			<shrsOrPrnAmt>
				<sshPrnamt>220442</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>220442</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PIONEER SOUTHWST ENRG PRTNR</nameOfIssuer>
			<titleOfClass>UNIT LP INT</titleOfClass>
			<cusip>72388B106</cusip>
			<value>9975</value>
			<shrsOrPrnAmt>
				<sshPrnamt>291000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>291000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PLAINS ALL AMERN PIPELINE L</nameOfIssuer>
			<titleOfClass>UNIT LTD PARTN</titleOfClass>
			<cusip>726503105</cusip>
			<value>867108</value>
			<shrsOrPrnAmt>
				<sshPrnamt>15536790</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>14581563</Sole>
				<Shared>0</Shared>
				<None>955227</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>QUESTAR CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>748356102</cusip>
			<value>30040</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1259550</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1259550</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>RANGE RES CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>75281A109</cusip>
			<value>19789</value>
			<shrsOrPrnAmt>
				<sshPrnamt>255934</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>255934</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>REGENCY ENERGY PARTNERS L P</nameOfIssuer>
			<titleOfClass>COM UNITS L P</titleOfClass>
			<cusip>75885Y107</cusip>
			<value>456420</value>
			<shrsOrPrnAmt>
				<sshPrnamt>16923249</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>16265229</Sole>
				<Shared>0</Shared>
				<None>658020</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ROSE ROCK MIDSTREAM L P</nameOfIssuer>
			<titleOfClass>COM U REP LTD</titleOfClass>
			<cusip>777149105</cusip>
			<value>16067</value>
			<shrsOrPrnAmt>
				<sshPrnamt>438745</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>438745</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ROYAL DUTCH SHELL PLC</nameOfIssuer>
			<titleOfClass>SPONS ADR A</titleOfClass>
			<cusip>780259206</cusip>
			<value>7305</value>
			<shrsOrPrnAmt>
				<sshPrnamt>114500</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>114500</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SCHLUMBERGER LTD</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>806857108</cusip>
			<value>2</value>
			<shrsOrPrnAmt>
				<sshPrnamt>21</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>21</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SEADRILL PARTNERS LLC</nameOfIssuer>
			<titleOfClass>COMUNIT REP LB</titleOfClass>
			<cusip>Y7545W109</cusip>
			<value>2642</value>
			<shrsOrPrnAmt>
				<sshPrnamt>90000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>90000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SEMGROUP CORP</nameOfIssuer>
			<titleOfClass>CL A</titleOfClass>
			<cusip>81663A105</cusip>
			<value>20454</value>
			<shrsOrPrnAmt>
				<sshPrnamt>379760</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>379760</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SEMPRA ENERGY</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>816851109</cusip>
			<value>8651</value>
			<shrsOrPrnAmt>
				<sshPrnamt>105807</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>105807</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SOUTHERN CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>842587107</cusip>
			<value>0</value>
			<shrsOrPrnAmt>
				<sshPrnamt>11</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>11</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SOUTHWESTERN ENERGY CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>845467109</cusip>
			<value>5577</value>
			<shrsOrPrnAmt>
				<sshPrnamt>152680</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>152680</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SPECTRA ENERGY CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>847560109</cusip>
			<value>205984</value>
			<shrsOrPrnAmt>
				<sshPrnamt>5977469</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>5723634</Sole>
				<Shared>0</Shared>
				<None>253835</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SPECTRA ENERGY PARTNERS LP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>84756N109</cusip>
			<value>364924</value>
			<shrsOrPrnAmt>
				<sshPrnamt>7933127</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>7646122</Sole>
				<Shared>0</Shared>
				<None>287005</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SUMMIT MIDSTREAM PARTNERS LP</nameOfIssuer>
			<titleOfClass>COM UNIT LTD</titleOfClass>
			<cusip>866142102</cusip>
			<value>18899</value>
			<shrsOrPrnAmt>
				<sshPrnamt>553400</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>553400</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SUNCOR ENERGY INC NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>867224107</cusip>
			<value>5550</value>
			<shrsOrPrnAmt>
				<sshPrnamt>188215</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>188215</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SUNOCO LOGISTICS PRTNRS L P</nameOfIssuer>
			<titleOfClass>COM UNITS</titleOfClass>
			<cusip>86764L108</cusip>
			<value>580520</value>
			<shrsOrPrnAmt>
				<sshPrnamt>9077716</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>8573291</Sole>
				<Shared>0</Shared>
				<None>504425</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>TARGA RESOURCES PARTNERS LP</nameOfIssuer>
			<titleOfClass>COM UNIT</titleOfClass>
			<cusip>87611X105</cusip>
			<value>288604</value>
			<shrsOrPrnAmt>
				<sshPrnamt>5720592</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>5434506</Sole>
				<Shared>0</Shared>
				<None>286086</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>TARGA RES CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>87612G101</cusip>
			<value>27289</value>
			<shrsOrPrnAmt>
				<sshPrnamt>424209</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>424209</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>TC PIPELINES LP</nameOfIssuer>
			<titleOfClass>UT COM LTD PRT</titleOfClass>
			<cusip>87233Q108</cusip>
			<value>80743</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1672400</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1672400</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>TEEKAY LNG PARTNERS L P</nameOfIssuer>
			<titleOfClass>PRTNRSP UNITS</titleOfClass>
			<cusip>Y8564M105</cusip>
			<value>2338</value>
			<shrsOrPrnAmt>
				<sshPrnamt>53500</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>53500</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>TEEKAY OFFSHORE PARTNERS L P</nameOfIssuer>
			<titleOfClass>PARTNERSHIP UN</titleOfClass>
			<cusip>Y8565J101</cusip>
			<value>8963</value>
			<shrsOrPrnAmt>
				<sshPrnamt>276030</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>276030</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>TESORO LOGISTICS LP</nameOfIssuer>
			<titleOfClass>COM UNIT LP</titleOfClass>
			<cusip>88160T107</cusip>
			<value>203197</value>
			<shrsOrPrnAmt>
				<sshPrnamt>3360848</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>3138044</Sole>
				<Shared>0</Shared>
				<None>222804</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>TRANSCANADA CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>89353D107</cusip>
			<value>62350</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1446309</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>1446309</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>TRINITY INDS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>896522109</cusip>
			<value>3</value>
			<shrsOrPrnAmt>
				<sshPrnamt>66</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>66</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>VALERO ENERGY CORP NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>91913Y100</cusip>
			<value>2</value>
			<shrsOrPrnAmt>
				<sshPrnamt>53</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>53</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>VANGUARD NATURAL RESOURCES L</nameOfIssuer>
			<titleOfClass>COM UNIT</titleOfClass>
			<cusip>92205F106</cusip>
			<value>8094</value>
			<shrsOrPrnAmt>
				<sshPrnamt>290100</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>290100</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WESTERN GAS EQUITY PARTNERS</nameOfIssuer>
			<titleOfClass>COMUNT LTD PT</titleOfClass>
			<cusip>95825R103</cusip>
			<value>92113</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2237392</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>2056004</Sole>
				<Shared>0</Shared>
				<None>181388</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WESTERN GAS PARTNERS LP</nameOfIssuer>
			<titleOfClass>COM UNIT LP IN</titleOfClass>
			<cusip>958254104</cusip>
			<value>416712</value>
			<shrsOrPrnAmt>
				<sshPrnamt>6421819</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>6070552</Sole>
				<Shared>0</Shared>
				<None>351267</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WESTERN REFNG INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>959319104</cusip>
			<value>1</value>
			<shrsOrPrnAmt>
				<sshPrnamt>25</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>25</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WESTLAKE CHEM CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>960413102</cusip>
			<value>3</value>
			<shrsOrPrnAmt>
				<sshPrnamt>36</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>36</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WHITING PETE CORP NEW</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>966387102</cusip>
			<value>10419</value>
			<shrsOrPrnAmt>
				<sshPrnamt>226057</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>226057</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WILLIAMS COS INC DEL</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>969457100</cusip>
			<value>253098</value>
			<shrsOrPrnAmt>
				<sshPrnamt>7794820</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>7308763</Sole>
				<Shared>0</Shared>
				<None>486057</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WILLIAMS PARTNERS L P</nameOfIssuer>
			<titleOfClass>COM UNIT L P</titleOfClass>
			<cusip>96950F104</cusip>
			<value>231750</value>
			<shrsOrPrnAmt>
				<sshPrnamt>4491287</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>4491287</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>WISCONSIN ENERGY CORP</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>976657106</cusip>
			<value>8904</value>
			<shrsOrPrnAmt>
				<sshPrnamt>217213</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<otherManager>N/A</otherManager>
			<votingAuthority>
				<Sole>217213</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
</informationTable>
