苹果酸脱氢酶和葡萄糖-6-磷酸脱氢酶，用于研究伴放线放线杆菌遗传多样性的关键标志物。

Malate dehydrogenase and glucose-6-phosphate dehydrogenase, key markers for studying the genetic diversity of Actinobacillus actinomycetemcomitans.

作者信息

Shah H N, Andrews D M

机构信息

Department of Microbiology, Eastman Dental Institute, University of London, UK.

出版信息

FEMS Microbiol Lett. 1994 Sep 15;122(1-2):69-73. doi: 10.1111/j.1574-6968.1994.tb07145.x.

DOI:10.1111/j.1574-6968.1994.tb07145.x

PMID:7958779

Abstract

Cell-free extracts of strains belonging to the 5 serotypes of A. actinomycetemcomitans were screened for several enzymes. Enzymes representative of the pentose phosphate pathway/hexose monophosphate shunt and the TCA cycle were present. Of these glucose-6-phosphate dehydrogenase (G6PDH) and malate dehydrogenase (MDH) were the most readily detected and stable. MDH and G6PDH retained more than 50% of their activities at alkaline pHs (10-11) for up to 6 h and 3 h at 25 degrees C, respectively, while at pH 6.5, 50% of their activities were lost within 2-3 h. The Km for malate oxidation catalysed by MDH was 5.8 x 10(-4) M while that for glucose-6-phosphate oxidation was 2.0 x 10(-4) M. The pH optima for MDH and G6PDH oxidation activities were 10 and 9.5, respectively. Among the 5 designated serotypes of A. actinomycetemcomitans three groups were delineated by multilocus enzyme electrophoresis using MDH and G6PDH.

摘要

对属于伴放线放线杆菌5种血清型的菌株的无细胞提取物进行了几种酶的筛选。存在代表磷酸戊糖途径/磷酸己糖支路和三羧酸循环的酶。其中，葡萄糖-6-磷酸脱氢酶（G6PDH）和苹果酸脱氢酶（MDH）最容易检测到且最稳定。MDH和G6PDH在碱性pH值（10 - 11）下，在25℃分别可保持6小时和3小时以上其活性的50%以上，而在pH 6.5时，2 - 3小时内其活性丧失50%。MDH催化苹果酸氧化的Km为5.8×10⁻⁴ M，而葡萄糖-6-磷酸氧化的Km为2.0×10⁻⁴ M。MDH和G6PDH氧化活性的最适pH分别为10和9.5。在伴放线放线杆菌的5种指定血清型中，使用MDH和G6PDH通过多位点酶电泳划分出了三组。