DeAngelis P L, Yang N, Weigel P H
Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77555-0647.
Biochem Biophys Res Commun. 1994 Feb 28;199(1):1-10. doi: 10.1006/bbrc.1994.1184.
We recently cloned the hyaluronan synthase gene (hasA) from Streptococcus pyogenes (DeAngelis et al., J. Biol. Chem. 268, 19181, 1993). Since this is the first glycosaminoglycan synthase gene to be cloned and these enzymes have also not been purified, nothing is yet known at the molecular level about the similarity or relatedness of hyaluronan synthase to other gene products. We found several proteins in the sequence database with substantial similarities to hyaluronan synthase (HasA), including NodC from Rhizobium, DG42 from Xenopus, and the three chitin synthases (Chs) from Saccharomyces. Like HasA, NodC and the Chs proteins all have at least an N-acetylglucosaminyl transferase activity in common and are membrane-associated. The polymerase chain reaction was also used to show that HasA, and probably the two gene operon for hyaluronan biosynthesis (hasA/hasB), is highly conserved among Group A streptococcal strains. In nine strains, isolated from 1917 through 1993, only five silent mutations were detected. The results show that hyaluronan synthase is highly conserved within Group A strains, although another virulence factor, the M protein, varies considerably in these same strains.
我们最近从化脓性链球菌中克隆了透明质酸合酶基因（hasA）（DeAngelis等人，《生物化学杂志》，第268卷，第19181页，1993年）。由于这是第一个被克隆的糖胺聚糖合酶基因，而且这些酶也尚未得到纯化，因此在分子水平上，关于透明质酸合酶与其他基因产物的相似性或相关性还一无所知。我们在序列数据库中发现了几种与透明质酸合酶（HasA）有显著相似性的蛋白质，包括根瘤菌的NodC、非洲爪蟾的DG42以及酿酒酵母的三种几丁质合酶（Chs）。与HasA一样，NodC和Chs蛋白都至少具有共同的N - 乙酰葡糖胺基转移酶活性，并且都与膜相关。聚合酶链反应也被用于表明，HasA以及可能的透明质酸生物合成双基因操纵子（hasA/hasB）在A组链球菌菌株中高度保守。在1917年至1993年分离出的9个菌株中，仅检测到5个沉默突变。结果表明，透明质酸合酶在A组菌株中高度保守，尽管另一种毒力因子M蛋白在这些相同的菌株中差异很大。
