Penicillin-binding proteins of Streptomyces cacaoi, Streptomyces olivaceus, and Streptomyces clavuligerus

Ogawara, Hiroshi; Horikawa, Susumu

doi:10.1128/aac.17.1.1

Cited by 30 publications

(19 citation statements)

References 23 publications

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“…Although BLIP is active against the β-lactamase of S. clavuligerus, it does not seem to affect the innate resistance of S. clavuligerus to penicillin G either in surface-grown or in liquid cultures. This result is in agreement with previous findings that the resistance of S. clavuligerus cultures to β-lactam antibiotics is a result of the production of penicillin-binding proteins having low affinity for β-lactams (Ogawara & Horikawa, 1980 ;Paradkar et al, 1998).…”

Section: Discussionsupporting

confidence: 83%

Construction and analysis of β-lactamase-inhibitory protein (BLIP) non-producer mutants of Streptomyces clavuligerus The GenBank accession number for the sequence determined in this work is M34538.

2001

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The gene encoding BLIP, a beta-lactamase-inhibitory protein, was disrupted in wild-type Streptomyces clavuligerus and in a clavulanic acid non-producing mutant. The resulting BLIP mutant and BLIP/clavulanic acid double mutant showed no residual proteinaceous β-lactamase-inhibitory activity, indicating that only a single β-lactamase-inhibitory protein exists in S. clavuligerus. The lack of any proteinaceous β-lactamase-inhibitory activity in the bli and bli/claR mutants also indicates that BLP, the BLIP-like protein, encoded by S.clavuligerus does not possess β-lactamase-inhibitory activity despite its similarity to BLIP. The bli mutant and the bli/claR double mutant did not show any aberrant growth morphology, sporulation defects, or alterations in cephamycin C production or penicillin G resistance when compared to wildtype S. clavuligerus or to the claR single mutant. Mutants bearing the bli gene disruption did show an elevated level of production of clavam-2-carboxylate and hydroxymethyl clavam as well as clavulanic acid. This phenomenon was observed in the middle stages of production of these clavams but was not detected during maximum production. The production of BLIP was also determined to be down-regulated in a ccaR mutant, lacking the pathwayspecific transcriptional regulator required for production of cephamycin C and clavulanic acid. Sequencing of the regions flanking the bli gene showed the presence of a partial open reading frame that encodes a DNA-binding protein, and several open reading frames apparently involved in the production of an ABC transporter.

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Section: Discussionsupporting

confidence: 83%

Construction and analysis of β-lactamase-inhibitory protein (BLIP) non-producer mutants of Streptomyces clavuligerus The GenBank accession number for the sequence determined in this work is M34538.

2001

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“…Our results indicate that PBP4 and other N. lactamdurans PBPs do not bind cephamycin, which most likely contributes to the resistance of N. lactamdurans to its own antibiotic. Similar results were reported by Ogawara and Horikawa (1980) in S. clavuligerus, another cephamycin-producing strain.…”

supporting

confidence: 78%

“…represented by a group of oxacillin-hydrolysing 3-lactamases (Forsman et al, 1990). Several Streptomyces strains produce extracellular 3-lactamases, all of those studied belonging to class A (Ogawara and Horikawa, 1980 (Piepersberg et al, 1988;Kirby, 1991). It is well known that several actinomycetes, including species of the genera Streptomyces (Ogawara and Horikawa, 1980;Forsman et al, 1990) and Actinomadura (Ghuysen, 1991) lactamase in actinomycetes is always associated with the presence of a ,B-lactam biosynthetic cluster, or with silent 3-lactam biosynthetic genes.…”

mentioning

confidence: 99%

Genes for a beta-lactamase, a penicillin-binding protein and a transmembrane protein are clustered with the cephamycin biosynthetic genes in Nocardia lactamdurans.

1993

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Three genes encoding a typical beta‐lactamase, a penicillin‐binding protein (PBP4) and a transmembrane protein are located in the cluster of cephamycin biosynthetic genes in Nocardia lactamdurans. The similarity of the N. lactamdurans beta‐lactamase to class A beta‐lactamases from clinical isolates supports the hypothesis that antibiotic resistance genes in pathogenic bacteria are derived from antibiotic‐producing organisms. The beta‐lactamase is secreted and is active against penicillins (including the biosynthetic intermediates penicillin N and isopenicillin N), but not against cephamycin C. The beta‐lactamase is synthesized during the active growth phase, prior to the formation of three cephamycin biosynthetic enzymes. The PBP of N. lactamdurans is a low‐M(r) protein that is very similar to DD‐carboxypeptidases of Streptomyces and Actinomadura. The pbp gene product expressed in Streptomyces lividans accumulates in the membrane fraction. By disruption of N. lactamdurans protoplasts, the PBP4 was shown to be located in the plasma membrane. Eight PBPs were found in the membranes of N. lactamdurans, none of which bind cephamycin C, which explains the resistance of this strain to its own antibiotic. A transmembrane protein encoded by the cmcT gene of the cluster also accumulates in the membrane fraction and is probably related to the control of synthesis and secretion of the antibiotic. A balanced synthesis of beta‐lactam antibiotics, beta‐lactamase and PBP is postulated to be critical for the survival of beta‐lactam‐producing actinomycetes.

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“…In addition, these species frequently possess PBPs with low affinities for penicillin, in comparison with PBPs of other gram-negative and gram-positive bacteria, and these PBPs are thought to contribute more to their intrinsic resistance than do ␤-lactamases (33). PBPs with even lower affinities for penicillin were detected among some penicillin-and cephalosporin-producing species, including S. clavuligerus, and therefore resistance in ␤-lactam producers is also thought to involve low-affinity PBPs (26,32,34). Although ␤-lactamases are not readily detectable in penicillin and cephalosporin producers, their presence and role in resistance cannot be ruled out.…”

mentioning

confidence: 97%

Molecular analysis of a beta-lactam resistance gene encoded within the cephamycin gene cluster of Streptomyces clavuligerus

et al. 1996

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A Streptomyces clavuligerus gene (designated pcbR) which is located immediately downstream from the gene encoding isopenicillin N synthase in the cephamycin gene cluster was characterized. Nucleotide sequence analysis and database searching of PcbR identified a significant similarity between PcbR and proteins belonging to the family of high-molecular-weight group B penicillin-binding proteins (PBPs). Eight of nine boxes (motifs) conserved within this family of proteins are present in the PcbR protein sequence in the same order and with approximately the same spacing between them. When a mutant disrupted in pcbR was constructed by gene replacement, the resulting pcbR mutant exhibited a significant decrease in its resistance to benzylpenicillin and cephalosporins, indicating that pcbR is involved in ␤-lactam resistance in this organism. Western blot (immunoblot) analysis of S. clavuligerus cell membranes using PcbR-specific antibodies suggested that PcbR is a membrane protein. PcbR was also present in cell membranes when expressed in Escherichia coli and was able to bind radioactive penicillin in a PBP assay, suggesting that PcbR is a PBP. When genomic DNAs from several actinomycetes were probed with pcbR, hybridization was observed to some but not all ␤-lactam-producing actinomycetes.

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Penicillin-binding proteins of Streptomyces cacaoi, Streptomyces olivaceus, and Streptomyces clavuligerus

Cited by 30 publications

References 23 publications

Construction and analysis of β-lactamase-inhibitory protein (BLIP) non-producer mutants of Streptomyces clavuligerus The GenBank accession number for the sequence determined in this work is M34538.

Construction and analysis of β-lactamase-inhibitory protein (BLIP) non-producer mutants of Streptomyces clavuligerus The GenBank accession number for the sequence determined in this work is M34538.

Genes for a beta-lactamase, a penicillin-binding protein and a transmembrane protein are clustered with the cephamycin biosynthetic genes in Nocardia lactamdurans.

Molecular analysis of a beta-lactam resistance gene encoded within the cephamycin gene cluster of Streptomyces clavuligerus

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