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Penicillin-binding protein 4 overproduction increases beta-lactam resistance in Staphylococcus aureus.

ABSTRACT: The Staphylococcus aureus mutant strain PVI selected in vitro for methicillin resistance overexpressed penicillin-binding protein (PBP) 4. In the wild-type parent strain the pbp4 gene was separated by 419 nucleotides from a divergently transcribed abcA locus coding for an ATP-binding cassette transporter. The mutant PVI was shown to have a deletion in the pbp4-abcA promoter region that affected pbp4 transcription but not expression of abcA. Introduction of the pbp4 gene plus the mutant promoter region into different genetic backgrounds revealed that PBP 4 overproduction was sufficient to increase in vitro-acquired methicillin resistance independently of other chromosomal genes. The role of the AbcA transporter in methicillin resistance remained unknown.

SUBMITTER: Henze UU

PROVIDER: S-EPMC163484 | biostudies-other | 1996 Sep

REPOSITORIES: biostudies-other

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Penicillin-binding protein 4 overproduction increases beta-lactam resistance in Staphylococcus aureus.

Henze U U UU Berger-Bächi B B

Antimicrobial agents and chemotherapy 19960901 9

The Staphylococcus aureus mutant strain PVI selected in vitro for methicillin resistance overexpressed penicillin-binding protein (PBP) 4. In the wild-type parent strain the pbp4 gene was separated by 419 nucleotides from a divergently transcribed abcA locus coding for an ATP-binding cassette transporter. The mutant PVI was shown to have a deletion in the pbp4-abcA promoter region that affected pbp4 transcription but not expression of abcA. Introduction of the pbp4 gene plus the mutant promoter ...[more]

PMID: 8878592

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