Pseudomurein endoisopeptidases PeiW and PeiP, two moderately related members of a novel family of proteases produced in Methanothermobacter strains.
Sequence comparison of pseudomurein endoisopeptidases PeiW encoded by the defective prophage PsiM100 of Methanothermobacter wolfeii, and PeiP encoded by phage PsiM2 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 degrees C and 6.4 for His-tagged PeiP and 71 degrees 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.
Luo
Yongneng
Y
Institute of Microbiology, Swiss Federal Institute of Technology Zürich, Schmelzbergstrasse 7, CH-8092, Zürich, Switzerland.
Pfister
Peter
P
Leisinger
Thomas
T
Wasserfallen
Alain
A
D000595:Amino Acid Sequence; D002413:Cations, Divalent / Q000494:pharmacology; D003001:Cloning, Molecular; D004492:Edetic Acid / Q000494:pharmacology; D010450:Endopeptidases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004789:Enzyme Activation; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D017013:Methanobacteriaceae / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA
D002413:Cations, Divalent; C051467:peptidoglycan endopeptidase; D004492:Edetic Acid; D010450:Endopeptidases