title: Reconstruction of Escherichia coli mrcA (PBP 1a) mutants lacking multiple combinations of penicillin binding proteins.
abstract: Previously, we constructed a set of mutants from which eight penicillin binding protein (PBP) genes were deleted in 192 combinations from Escherichia coli (S. A. Denome, P. K. Elf, T. A. Henderson, D. E. Nelson, and K. D. Young, J. Bacteriol. 181:3981-3993, 1999). Although these mutants were constructed correctly as determined by restriction mapping and the absence of relevant protein products, we recently discovered by PCR mapping that strains from which mrcA (PBP 1a) was deleted were also missing two neighboring genes of unknown function (yrfE and yrfF). We created a new deletion mutation in mrcA and reconstructed 63 strains lacking PBP 1a and other PBP mutant combinations. The new mrcA mutants do not exhibit mucoidy, phage resistance, temperature sensitivity, growth rate defects, or antibiotic resistance, suggesting that these phenotypes require the loss of either yrfE or yrfF alone or in combination with the absence of multiple PBPs.
authors.affiliation: Department of Microbiology and Immunology, University of North Dakota School of Medicine, Grand Forks, North Dakota 58202-9037, USA.
authors.forename: B M
authors.initials: BM
authors.lastname: Meberg
authors.forename: F C
authors.initials: FC
authors.lastname: Sailer
authors.forename: D E
authors.initials: DE
authors.lastname: Nelson
authors.forename: K D
authors.initials: KD
authors.lastname: Young
mesh_terms: D001426:Bacterial Proteins; D002352:Carrier Proteins; D004926:Escherichia coli / Q000235:genetics*; D005798:Genes, Bacterial; D006602:Hexosyltransferases / Q000235:genetics*; D009097:Multienzyme Complexes / Q000235:genetics*; D002267:Muramoylpentapeptide Carboxypeptidase; D009154:Mutation; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases / Q000235:genetics*; D010641:Phenotype
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D009097:Multienzyme Complexes; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase