Open AccessThe lytic enzyme in bacteriophage ψM1‐induced lysates of Methanobacterium thermoautotrophicum Marburg
Author(s) -
Stax Dietmar,
Hermann René,
Falchetto Rocco,
Leisinger Thomas
Publication year - 1992
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1992.tb14073.x
Subject(s) - lytic cycle , endopeptidase , polyclonal antibodies , bacteriophage , enzyme , biochemistry , microbiology and biotechnology , biology , methanobacterium , chemistry , antibody , virus , gene , virology , escherichia coli , immunology , archaea
The lytic enzyme from bacteriophage ψM1‐induced lysates of Methanobacterium thermoautotrophicum was purified approx. 80‐fold to near electrophoretic homogeneity. It was a 31‐kDa monomeric, oxygen‐sensitive pseudomurein endopeptidase hydrolysing the ?‐Ala‐Lys bond of pseudomurein. Pseudomurein endopeptidase‐specific polyclonal antibodies reacted with a 31‐kDa protein in crude extracts of non‐infected host cells. This cross‐reacting protein was purified. It did not exhibit lytic activity but its N‐terminus was identical with the N‐terminus of pseudomurein endopeptidase. The 31‐kDa protein thus probably represents a pseudomurein endopeptidase whose autolytic activity is under control in non‐infected, but deregulated in phage ψM1‐infected cells. Its preferential location in the cell‐wall area was demonstrated by immuno‐electron microscopy and argued for a role of pseudomurein endopeptidase in the expansion of the cell wall during growth.