Effect of D-amino acids on Escherichia coli strains with impaired penicillin-binding proteins.
Escherichia coli cells growing in the presence of some D-amino acids incorporate D-amino acid into the peptidoglycan layer of the cell wall by a mechanism most likely independent of the normal biosynthetic pathway. Analysis of the sensitivity of mutant strains with impaired penicillin-binding proteins (PBP) to D-amino acids indicated that ponB and DD-endopeptidase/DD-carboxypeptidase-I-defective strains are hypersensitive to D-amino acids. D-tryptophan containing peptidoglycan was found to be more susceptible to the action of lytic transglycosilases than native material, which could explain in part the harmful effects of D-amino acids. ponB strains carrying additional mutations suppressing hypersensitivity to D-amino acids have been obtained and the results of their initial characterization are reported.
Centro de Biologia Molecular CSIC-UAM, Facultad de Ciencias, Universidad Autónoma de Madrid.
M
M
Caparrós
J L
JL
Torrecuadrada
M A
MA
de Pedro
D000596:Amino Acids / Q000737:chemistry / Q000494:pharmacology*; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D005798:Genes, Bacterial; D006602:Hexosyltransferases / Q000378:metabolism; D008715:Methionine / Q000737:chemistry / Q000494:pharmacology; D002267:Muramoylpentapeptide Carboxypeptidase / Q000378:metabolism*; D009154:Mutation; D046915:Penicillin-Binding Proteins; D010457:Peptidoglycan / Q000378:metabolism; D046928:Peptidoglycan Glycosyltransferase; D010458:Peptidyl Transferases; D013237:Stereoisomerism; D014364:Tryptophan / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology
D000596:Amino Acids; D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D010457:Peptidoglycan; D014364:Tryptophan; D008715:Methionine; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D046928:Peptidoglycan Glycosyltransferase; D002267:Muramoylpentapeptide Carboxypeptidase