Mukhopadhyay N K, Majumder S, Ghosh S K, Bose S K
Biochem J. 1986 May 1;235(3):639-43. doi: 10.1042/bj2350639.
Mycobacillin synthetase lacks aspartic acid racemase, alanine racemase and glutamic acid racemase activities. The enzyme also does not respond to ATP-[32P]Pi exchange, nor does it catalyse the antibiotic synthesis in presence of amino acids of configuration opposite to that present in the molecule. Preincubation with optical isomers of opposite configuration inhibited the ATP-[32P]Pi exchange reaction to the extent of 60-90%. None of the three fractions of mycobacillin synthetase contained a pantothenic acid arm. Two molecules of ATP are required to synthesize one peptide bond of mycobacillin. Intermediate peptides of mycobacillin are not covalently linked to the three-fraction mycobacillin synthetase.
分枝杆菌素合成酶缺乏天冬氨酸消旋酶、丙氨酸消旋酶和谷氨酸消旋酶活性。该酶也不参与ATP-[32P]Pi交换反应，在存在与分子中氨基酸构型相反的氨基酸时，它也不催化抗生素的合成。与构型相反的旋光异构体预孵育会使ATP-[32P]Pi交换反应受到60%-90%的抑制。分枝杆菌素合成酶的三个组分均不含有泛酸臂。合成一个分枝杆菌素肽键需要两分子ATP。分枝杆菌素的中间肽段与三组分分枝杆菌素合成酶没有共价连接。
