Pseudomurein endoisopeptidases PeiW and PeiP, two moderately related members of a novel family of proteases produced in Methanothermobacter strains
- 作者：Luo ; Yongneng ; Pfister ; Peter ; Leisinger ; Thomas ; Wasserfallen ; Alain
- 关键词：Archaeon ; Methanothermobacter ; Enzyme characterization ; Pseudomurein endoisopeptidase ; Metal-activated protease
- 刊名：FEMS Microbiology Letters
- 出版年：2002
- 期刊代码：34_03781097
- 类别：imm
- 出版时间：February 19, 2002
- 卷：208
- 期：1
- 页码：47-51
- 文件大小：572 K
摘要
Sequence comparison of pseudomurein endoisopeptidases PeiW encoded by the defective prophage ΨM100 of Methanothermobacter wolfeii, and PeiP encoded by phage ΨM2 of Methanothermobacter marburgensis, revealed that the two enzymes share only limited similarity. Their amino acid sequences comprise an N-terminal domain characterized by the presence of direct repeats and a C-terminal domain with a catalytic triad C-H-D as in thiol proteases and animal transglutaminases. Both PeiW and PeiP catalyze the in vitro lysis of M. marburgensis cells under reducing conditions and exhibit characteristics of metal-activated peptidases. Optimal temperature and pH were determined to be 63°C and 6.4 for His-tagged PeiP and 71°C and 6.4 for His-tagged PeiW, respectively. Database search results suggest that PeiW and PeiP are the first two experimentally identified members of a novel family of proteases in a superfamily of archaeal, bacterial, and eukaryotic protein homologs of animal transglutaminases.