Arslan E, Schulz H, Zufferey R, Künzler P, Thöny-Meyer L
Mikrobiologisches Institut, Eidgenössische Technische Hochschule, Schmelzbergstrasse 7, Zürich, CH-8092, Switzerland.
Biochem Biophys Res Commun. 1998 Oct 29;251(3):744-7. doi: 10.1006/bbrc.1998.9549.
We report on a system to improve expression of mature c-type cytochromes in Escherichia coli. It is based on the use of plasmid pEC86 that expresses the E. coli cytochrome c maturation genes ccmABCDEFGH constitutively, whereby the production of both endogenous and foreign c-type cytochromes was increased substantially. The periplasmic soluble domains of the c-type cytochrome subunits FixO and FixP of the Bradyrhizobium japonicum cbb3 oxidase could be expressed in E. coli only when pEC86 was provided in a degP-deficient strain. This shows that a stimulation of heme attachment by the Ccm maturase system combined with the diminished proteolytic activity in the periplasm can increase c-type cytochrome yields.
我们报道了一种用于提高大肠杆菌中成熟c型细胞色素表达的系统。该系统基于使用质粒pEC86，其组成型表达大肠杆菌细胞色素c成熟基因ccmABCDEFGH，从而使内源性和外源性c型细胞色素的产量大幅增加。只有在degP缺陷型菌株中提供pEC86时，日本慢生根瘤菌cbb3氧化酶的c型细胞色素亚基FixO和FixP的周质可溶性结构域才能在大肠杆菌中表达。这表明Ccm成熟酶系统对血红素附着的刺激作用与周质中蛋白水解活性的降低相结合，可以提高c型细胞色素的产量。
