Kotb M, Geller A M, Markham G D, Kredich N M, De La Rosa J, Beachey E H
Veterans Administration Medical Center, Memphis, TN 38104.
Biochim Biophys Acta. 1990 Sep 3;1040(2):137-44. doi: 10.1016/0167-4838(90)90068-q.
Although the physical and kinetic properties of S-adenosylmethionine (AdoMet) synthetases from different sources are quite different, it appears that these enzymes have structurally or antigenically conserved regions as demonstrated by studies with AdoMet synthetase specific antibodies. Polyclonal anti-human lymphocyte AdoMet synthetase crossreacted with enzyme from rat liver (beta isozyme), Escherichia coli and yeast. In addition, polyclonal anti-E. coli enzyme and antibodies to synthetic peptides copying several regions of the yeast enzyme reacted with the human gamma and rat beta isozymes. Antibodies to yeast SAM1 encoded protein residues 6-21, 87-113 and 87-124 inhibited the activity of human lymphocyte AdoMet synthetase, while antibodies to residues 272-287 had no effect on the enzyme activity. Our results suggest that these conserved regions may be important in enzyme activity.
尽管来自不同来源的S-腺苷甲硫氨酸（AdoMet）合成酶的物理和动力学性质有很大差异，但研究表明，这些酶具有结构或抗原保守区域，如用AdoMet合成酶特异性抗体所证实的那样。多克隆抗人淋巴细胞AdoMet合成酶与大鼠肝脏（β同工酶）、大肠杆菌和酵母的酶发生交叉反应。此外，多克隆抗大肠杆菌酶以及针对复制酵母酶几个区域的合成肽的抗体与人γ同工酶和大鼠β同工酶发生反应。针对酵母SAM1编码蛋白残基6 - 21、87 - 113和87 - 124的抗体抑制人淋巴细胞AdoMet合成酶的活性，而针对残基272 - 287的抗体对酶活性没有影响。我们的结果表明，这些保守区域可能对酶活性很重要。
