were quantified by ESI-MS/MS. We show that CPT2 is active with medium (C8-C12) and long-chain (C14-C18) acyl-CoA esters, whereas virtually no activity was found with short- and very long-chain acyl-CoAs or with branched-chain amino acid oxidation intermediates. Trans-2-enoyl-CoA intermediates were also found to be poor substrates for CPT2. Inhibition studies performed revealed that trans-2-C16:1-CoA may
近年来,酰基肉碱已成为诊断线粒体
脂肪酸β-氧化(mFAO)和支链
氨基酸氧化障碍的重要
生物标志物,前提是它们反映了潜在的毒性酰基
辅酶A物种,在线粒体内积累在酶嵌段的上游。但是,这些中间体的起源仍然知之甚少。肉碱航天飞机成员肉碱棕榈酰转移酶2(C
PT2)可能参与了线粒体内由积累的酰基CoA代谢产物合成的酰基肉碱。为了解决这个问题,本文研究了C
PT2的底物特异性概况。将表达人C
PT2的啤酒酵母匀浆与饱和和不饱和的C2-C26酰基
辅酶A和支链
氨基酸氧化中间体孵育。通过ESI-MS / MS对产生的酰基肉碱进行定量。我们显示C
PT2与中等(C8-C12)和长链(C14-C18)酰基
辅酶A酯具有活性,而实际上未发现短链和长链酰基
辅酶A或支链
氨基具有活性酸氧化中间体。还发现反式-2-烯酰基-CoA中间体是C
PT2的不良底物。进行的抑制研究表明,trans-2-C16:1-CoA可以作为C
PT2的竞争性
抑制剂(K(i)为18