The utilization of alanine, glutamic acid, and serine as amino acid substrates for glycineN-acyltransferase
作者:Francois H. van der Westhuizen、Petrus J. Pretorius、Elardus Erasmus
DOI:10.1002/(sici)1099-0461(2000)14:2<102::aid-jbt6>3.0.co;2-h
日期:——
The conjugation of benzoyl-CoA with the aliphatic and acidic amino acids by glycine N-acyltransferase, as well as the amides of the latter group, was investigated. Bovine and human liver benzoyl-amino acid conjugation were investigated using electrospray ionization tandem mass spectrometry (ESI-MS-MS). Bovine glycine N-acyltransferase catalyzed conjugation of benzoyl-CoA with Gly (Km(Gly) = 6.2 mM)
研究了甘氨酸N-酰基转移酶与苯甲酰基辅酶A与脂肪族和酸性氨基酸的缀合以及后一组的酰胺。使用电喷雾电离串联质谱(ESI-MS-MS)研究了牛和人肝脏的苯甲酰氨基酸结合。牛甘氨酸N-酰基转移酶催化苯甲酰辅酶A与Gly(Km(Gly)= 6.2 mM),Asn(Km(Asn)= 129 mM),Gln(Km(Gln)= 353 mM),Ala(Km(Ala )= 1573 mM),Glu(Km(Glu)= 1148 mM)以及Ser处于顺序机制中。在人类形式的情况下,检测到与Gly(Km(Gly)= 6.4 mM),Ala(Km(Ala)= 997 mM)和Glu结合。这些替代缀合物的存在没有明显抑制牛甘氨酸N-酰基转移酶活性。考虑到形成这些结合物的水平相对较低,在体内正常条件下,它们不太可能对酰基氨基酸结合产生重大影响。然而,它们在代谢疾病状态下对酰基-氨基酸缀合的累积贡献可能证明对升高的酰基-CoA的解毒具有有益的贡献。