TY - JOUR
T1 - Remodeling of Cardiolipin by Phospholipid Transacylation
AU - Xu, Yang
AU - Kelley, Richard I.
AU - Blanck, Thomas J.J.
AU - Schlame, Michael
PY - 2003/12/19
Y1 - 2003/12/19
N2 - Mitochondrial cardiolipin (CL) contains unique fatty acid patterns, but it is not known how the characteristic molecular species of CL are formed. We found a novel reaction that transfers acyl groups from phosphatidylcholine or phosphatidylethanolamine to CL in mitochondria of rat liver and human lymphoblasts. Acyl transfer was stimulated by ADP, ATP, and ATPγS, but not by other nucleotides. Coenzyme A stimulated the reaction only in the absence of adenine nucleotides. Free fatty acids were not incorporated into CL under the same incubation condition. The transacylation required addition of exogenous CL or monolyso-CL, whereas dilyso-CL was not a substrate. Transacylase activity was decreased in lymphoblasts from patients with Barth syndrome (tafazzin deletion), and this was accompanied by drastic changes in the molecular composition of CL. In rat liver, where linoleic acid was the most abundant residue of CL, only linoleoyl groups were transferred into CL, but not oleoyl or arachidonoyl groups. We demonstrated complete remodeling of tetraoleoyl-CL to tetralinoleoyl-CL in rat liver mitochondria and identified the intermediates linoleoyl-trioleoyl-CL, dilinoleoyl-dioleoyl-CL, and trilinoleoyl-oleoyl-CL by high-performance liquid chromatography. The data suggest that CL is remodeled by acyl specific phospholipid transacylation and that tafazzin is an acyltransferase involved in this mechanism.
AB - Mitochondrial cardiolipin (CL) contains unique fatty acid patterns, but it is not known how the characteristic molecular species of CL are formed. We found a novel reaction that transfers acyl groups from phosphatidylcholine or phosphatidylethanolamine to CL in mitochondria of rat liver and human lymphoblasts. Acyl transfer was stimulated by ADP, ATP, and ATPγS, but not by other nucleotides. Coenzyme A stimulated the reaction only in the absence of adenine nucleotides. Free fatty acids were not incorporated into CL under the same incubation condition. The transacylation required addition of exogenous CL or monolyso-CL, whereas dilyso-CL was not a substrate. Transacylase activity was decreased in lymphoblasts from patients with Barth syndrome (tafazzin deletion), and this was accompanied by drastic changes in the molecular composition of CL. In rat liver, where linoleic acid was the most abundant residue of CL, only linoleoyl groups were transferred into CL, but not oleoyl or arachidonoyl groups. We demonstrated complete remodeling of tetraoleoyl-CL to tetralinoleoyl-CL in rat liver mitochondria and identified the intermediates linoleoyl-trioleoyl-CL, dilinoleoyl-dioleoyl-CL, and trilinoleoyl-oleoyl-CL by high-performance liquid chromatography. The data suggest that CL is remodeled by acyl specific phospholipid transacylation and that tafazzin is an acyltransferase involved in this mechanism.
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U2 - 10.1074/jbc.M307382200
DO - 10.1074/jbc.M307382200
M3 - Article
C2 - 14551214
AN - SCOPUS:0345803935
SN - 0021-9258
VL - 278
SP - 51380
EP - 51385
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 51
ER -