You can manage bookmarks using lists, please log in to your user account for this.
Media type:
E-Article
Title:
Penicillin‐binding Protein 7/8 of Escherichia coli is a dd‐endopeptidase
Contributor:
Romeis, Tina;
Höltje, Joachim‐Volker
Published:
Wiley, 1994
Published in:
European Journal of Biochemistry, 224 (1994) 2, Seite 597-604
Language:
English
DOI:
10.1111/j.1432-1033.1994.00597.x
ISSN:
0014-2956;
1432-1033
Origination:
Footnote:
Description:
<jats:p>Penicillin‐binding protein 7 (PBP7) and its proteolytic degradation product PBP8 are shown to be soluble proteins, which can be set free from whole cells of <jats:italic>Escherichia coli</jats:italic> by an osmotic shock. The proteins are loosely associated with the membranes and are totally released into the supernatant in the presence of 1 M NaCl. Partial purification of PBP8 was accomplished by hydroxyapatite, heparin‐Sepharose and Monos chromatography. Murein <jats:italic>meso</jats:italic>‐diaminopimelate‐<jats:sc>d</jats:sc>‐alanine <jats:sc>dd</jats:sc>‐endopeptidase activity was demonstrated for both PBP7 and PBP8, which specifically hydrolyse the <jats:sc>dd</jats:sc>‐diaminopimelatealanine bonds in high‐molecular‐mass murein sacculi but fail to cleave these bonds in isolated dimeric muropeptides. The enzyme is inhibited by the ‘penem’β‐lactam antibiotic CGP31608 at a concentration of 0.25 μg/ml by 50%. Thus besides PBP4 and the <jats:italic>mepA</jats:italic> gene product, a third endopeptidase exists in <jats:italic>E. coli.</jats:italic></jats:p>