来自蚜虫内共生菌布赫纳氏菌（Buchnera aphidicola）的一段包含dapD-htrA-ilvI-ilvH-ftsL-ftsI-murE基因的DNA片段的序列分析。

Sequence analysis of a DNA fragment from buchnera aphidicola (Aphid endosymbiont) containing the genes dapD-htrA-ilvI-ilvH-ftsL-ftsI-murE.

作者信息

Thao ML, Baumann P

机构信息

Microbiology Section, University of California, Davis, CA 95616-8665, USA.

出版信息

Curr Microbiol. 1998 Sep;37(3):214-6. doi: 10.1007/s002849900365.

DOI:10.1007/s002849900365

PMID:9688822

Abstract

Buchnera aphidicola is a prokaryotic endosymbiont of the aphid Schizaphis graminum. One of the endosymbiont's functions is the synthesis of branched-chain amino acids. A 9.7-kilobase B. aphidicola chromosomal DNA fragment was cloned and sequenced and found to contain genes encoding acetohydroxy acid synthase (ilvIH), the first enzyme of the parallel pathway of isoleucine and valine biosynthesis. Previously we have detected ilvC and ilvD, encoding the two other enzymes of this pathway. In addition the DNA fragment contained genes for cell division (ftsL, ftsI), murein biosynthesis (murE), lysine biosynthesis (dapD) and a periplasmic protease (htrA). In these properties B. aphidicola resembles free-living bacteria.

摘要

蚜虫内共生菌是麦二叉蚜的一种原核内共生体。这种内共生体的功能之一是合成支链氨基酸。一个9.7千碱基的蚜虫内共生菌染色体DNA片段被克隆并测序，发现其包含编码乙酰羟酸合酶（ilvIH）的基因，该酶是异亮氨酸和缬氨酸生物合成平行途径的第一种酶。此前我们已检测到编码该途径另外两种酶的ilvC和ilvD。此外，该DNA片段还包含细胞分裂（ftsL、ftsI）、胞壁质生物合成（murE）、赖氨酸生物合成（dapD）和一种周质蛋白酶（htrA）的基因。在这些特性方面，蚜虫内共生菌类似于自由生活的细菌。