枯草芽孢杆菌细胞色素氧化酶突变体：两种aa3型氧化酶的生化分析及遗传学证据

Bacillus subtilis cytochrome oxidase mutants: biochemical analysis and genetic evidence for two aa3-type oxidases.

作者信息

van der Oost J, von Wachenfeld C, Hederstedt L, Saraste M

机构信息

European Molecular Biology Laboratory, Heidelberg, Germany.

出版信息

Mol Microbiol. 1991 Aug;5(8):2063-72. doi: 10.1111/j.1365-2958.1991.tb00829.x.

DOI:10.1111/j.1365-2958.1991.tb00829.x

PMID:1685007

Abstract

The ctaBCDEF genes coding for cytochrome c oxidase were found to reside adjacent to a regulatory gene ctaA at 127 degrees on the Bacillus subtilis chromosome. The structural genes for subunits I and II, ctaD and ctaC, were deleted by gene-replacement using a phleomycin-resistance marker. The mutant was unable to oxidize N,N,N',N'-tetramethyl-p-phenylene-diamine and oxidized cytochrome c at a significantly lower rate. Absorption spectra of the mutant and wild-type membranes confirmed the presence of two haem A-containing enzymes in B. subtilis. Another mutant, with a spontaneous deletion upstream from ctaC, was found to express neither of these enzymes. Radioactive haem-labelling was used to identify subunit II, which contains a haem C, and cytochrome c-550 among the membrane-bound c-type cytochromes of B. subtilis.

摘要

编码细胞色素c氧化酶的ctaBCDEF基因位于枯草芽孢杆菌染色体127°处的调控基因ctaA附近。使用博来霉素抗性标记通过基因置换删除了亚基I和II的结构基因ctaD和ctaC。该突变体无法氧化N，N，N'，N'-四甲基对苯二胺，并且以明显更低的速率氧化细胞色素c。突变体和野生型膜的吸收光谱证实枯草芽孢杆菌中存在两种含血红素A的酶。另一个在ctaC上游有自发缺失的突变体被发现不表达这两种酶中的任何一种。放射性血红素标记被用于在枯草芽孢杆菌的膜结合c型细胞色素中鉴定含有血红素C的亚基II和细胞色素c-550。