P. Liras

Amy as a reporter gene for promoter activity in Nocardia lactamdurans: comparison of promoters of the cephamycin cluster.

Chary, V K, De La Fuente, J L, Liras, P, Martin, J F

Promoter probe vectors containing the pA origin of replication and the Streptomyces griseus promoterless amy gene (encoding alpha-amylase) as reporter have been constructed to study transcription...

A two-protein component 7 alpha-cephem-methoxylase encoded by two genes of the cephamycin C cluster converts cephalosporin C to 7-methoxycephalosporin C.

Coque, J J, Enguita, F J, Martín, J F, Liras, P

Two genes, cmcI and cmcJ, corresponding to open reading frames 7 and 8 (ORF7 and ORF8) of the cephamycin C cluster of Nocardia lactamdurans encode enzymes that convert cephalosporin C to...

A regulatory gene (ccaR) required for cephamycin and clavulanic acid production in Streptomyces clavuligerus: amplification results in overproduction of both beta-lactam compounds.

Pérez-Llarena, F J, Liras, P, Rodríguez-García, A, Martín, J F

A regulatory gene (ccaR), located within the cephamycin gene cluster of Streptomyces clavuligerus, is linked to a gene (blp) encoding a protein similar to a beta-lactamase-inhibitory protein....

The bla gene of the cephamycin cluster of Streptomyces clavuligerus encodes a class A beta-lactamase of low enzymatic activity.

Pérez-Llarena, F, Martín, J F, Galleni, M, Coque, J J, Fuente, J L, Frère, J M, ...

A gene (bla) encoding a beta-lactamase is present in the cephamycin gene cluster of Streptomyces clavuligerus, the strain producing clavulanic acid and a beta-lactamase inhibitory protein. The bla...

Efficient plasmid transformation of the beta-lactam producer Streptomyces clavuligerus.

Garcia-Dominguez, M, Martin, J F, Mahro, B, Demain, A L, Liras, P

The conditions for optimal formation and regeneration of protoplasts of Streptomyces clavuligerus were established. The optimal temperature for regeneration of protoplasts and for transformation was...

Characterization of the Streptomyces clavuligerus argC gene encoding N-acetylglutamyl-phosphate reductase: expression in Streptomyces lividans and effect on clavulanic acid production.

Ludovice, M, Martin, J F, Carrachas, P, Liras, P

The argC gene of Streptomyces clavuligerus encoding N-acetylglutamyl-phosphate reductase (AGPR) has been cloned by complementation of argC mutants Streptomyces lividans 1674 and Escherichia coli...

Characterization, expression in Streptomyces lividans, and processing of the amylase of Streptomyces griseus IMRU 3570: two different amylases are derived from the same gene by an intracellular processing mechanism.

Garcia-Gonzalez, M D, Martin, J F, Vigal, T, Liras, P

Extracellular amylase in Streptomyces lividans was undetectable in starch-supplemented medium. However, S. lividans produced fivefold-higher levels of amylase than Streptomyces griseus IMRU 3570 when...

A gene encoding lysine 6-aminotransferase, which forms the beta-lactam precursor alpha-aminoadipic acid, is located in the cluster of cephamycin biosynthetic genes in Nocardia lactamdurans.

Coque, J J, Liras, P, Laiz, L, Martín, J F

A gene (lat) encoding lysine 6-aminotransferase was found upstream of the pcbAB (encoding alpha-aminoadipylcysteinyl-valine synthetase) and pcbC (encoding isopenicillin N synthase) genes in the...

Characterization of sugar uptake in wild-type Streptomyces clavuligerus, which is impaired in glucose uptake, and in a glucose-utilizing mutant.

Garcia-Dominguez, M, Martin, J F, Liras, P

Wild-type Streptomyces clavuligerus NRRL 3585 is unable to utilize glucose. A glucose-utilizing (gut-1) mutant of S. clavuligerus NRRL 3585 has been obtained by N-methyl-N'-nitro-N-nitrosoguanidine...

Utilization of ornithine and arginine as specific precursors of clavulanic acid.

Romero, J, Liras, P, Martín, J F

Ornithine and arginine (5 to 20 mM), but not glutamic acid or proline, exerted a concentration-dependent stimulatory effect on the biosynthesis of clavulanic acid in both resting-cell cultures and...

Cloning and characterization of the isopenicillin N synthase gene of Streptomyces griseus NRRL 3851 and studies of expression and complementation of the cephamycin pathway in Streptomyces clavuligerus.

García-Domínguez, M, Liras, P, Martín, J F

A gene, pcbC, encoding the isopenicillin N synthase of Streptomyces griseus NRRL 3851, has been cloned in a 6.4-kb Bg/II DNA fragment and located in an internal 1.55-kb PvuII segment by hybridization...

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

Coque, J J, Liras, P, Martín, J F

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....

Two Proteins with Ornithine Acetyltransferase Activity Show Different Functions in Streptomyces clavuligerus: Oat2 Modulates Clavulanic Acid Biosynthesis in Response to Arginine

De La Fuente, A., Martín, J. F., Rodríguez-García, A., Liras, P.

The oat2 gene, located in the clavulanic acid gene cluster in Streptomyces clavuligerus, is similar to argJ, which encodes N-acetylornithine:glutamic acid acetyltransferase activity. Purified...

New type of hexameric ornithine carbamoyltransferase with arginase activity in the cephamycin producers Streptomyces clavuligerus and Nocardia lactamdurans.

De La Fuente, J L, Martin, J F, Liras, P

The ornithine carbamoyltransferases (OTCases) from the beta-lactam-producing actinomycetes Streptomyces clavuligerus and Nocardia lactamdurans have been purified to near-homogeneity by...

Delta-1-piperideine-6-carboxylate dehydrogenase, a new enzyme that forms alpha-aminoadipate in Streptomyces clavuligerus and other cephamycin C-producing actinomycetes.

De La Fuente, J L, Rumbero, A, Martín, J F, Liras, P

Delta-1-Piperideine-6-carboxylate (P6C) dehydrogenase activity, which catalyses the conversion of P6C into alpha-aminoadipic acid, has been studied in the cephamycin C producer Streptomyces...

Amy as a reporter gene for promoter activity in Nocardia lactamdurans: comparison of promoters of the cephamycin cluster.

Chary, V K, De La Fuente, J L, Liras, P, Martin, J F

Promoter probe vectors containing the pA origin of replication and the Streptomyces griseus promoterless amy gene (encoding alpha-amylase) as reporter have been constructed to study transcription...

A two-protein component 7 alpha-cephem-methoxylase encoded by two genes of the cephamycin C cluster converts cephalosporin C to 7-methoxycephalosporin C.

Coque, J J, Enguita, F J, Martín, J F, Liras, P

Two genes, cmcI and cmcJ, corresponding to open reading frames 7 and 8 (ORF7 and ORF8) of the cephamycin C cluster of Nocardia lactamdurans encode enzymes that convert cephalosporin C to...

A regulatory gene (ccaR) required for cephamycin and clavulanic acid production in Streptomyces clavuligerus: amplification results in overproduction of both beta-lactam compounds.

Pérez-Llarena, F J, Liras, P, Rodríguez-García, A, Martín, J F

A regulatory gene (ccaR), located within the cephamycin gene cluster of Streptomyces clavuligerus, is linked to a gene (blp) encoding a protein similar to a beta-lactamase-inhibitory protein....

The bla gene of the cephamycin cluster of Streptomyces clavuligerus encodes a class A beta-lactamase of low enzymatic activity.

Pérez-Llarena, F, Martín, J F, Galleni, M, Coque, J J, Fuente, J L, Frère, J M, ...

A gene (bla) encoding a beta-lactamase is present in the cephamycin gene cluster of Streptomyces clavuligerus, the strain producing clavulanic acid and a beta-lactamase inhibitory protein. The bla...

Efficient plasmid transformation of the beta-lactam producer Streptomyces clavuligerus.

Garcia-Dominguez, M, Martin, J F, Mahro, B, Demain, A L, Liras, P

The conditions for optimal formation and regeneration of protoplasts of Streptomyces clavuligerus were established. The optimal temperature for regeneration of protoplasts and for transformation was...

Characterization of the Streptomyces clavuligerus argC gene encoding N-acetylglutamyl-phosphate reductase: expression in Streptomyces lividans and effect on clavulanic acid production.

Ludovice, M, Martin, J F, Carrachas, P, Liras, P

The argC gene of Streptomyces clavuligerus encoding N-acetylglutamyl-phosphate reductase (AGPR) has been cloned by complementation of argC mutants Streptomyces lividans 1674 and Escherichia coli...

Characterization, expression in Streptomyces lividans, and processing of the amylase of Streptomyces griseus IMRU 3570: two different amylases are derived from the same gene by an intracellular processing mechanism.

Garcia-Gonzalez, M D, Martin, J F, Vigal, T, Liras, P

Extracellular amylase in Streptomyces lividans was undetectable in starch-supplemented medium. However, S. lividans produced fivefold-higher levels of amylase than Streptomyces griseus IMRU 3570 when...

A gene encoding lysine 6-aminotransferase, which forms the beta-lactam precursor alpha-aminoadipic acid, is located in the cluster of cephamycin biosynthetic genes in Nocardia lactamdurans.

Coque, J J, Liras, P, Laiz, L, Martín, J F

A gene (lat) encoding lysine 6-aminotransferase was found upstream of the pcbAB (encoding alpha-aminoadipylcysteinyl-valine synthetase) and pcbC (encoding isopenicillin N synthase) genes in the...

Characterization of sugar uptake in wild-type Streptomyces clavuligerus, which is impaired in glucose uptake, and in a glucose-utilizing mutant.

Garcia-Dominguez, M, Martin, J F, Liras, P

Wild-type Streptomyces clavuligerus NRRL 3585 is unable to utilize glucose. A glucose-utilizing (gut-1) mutant of S. clavuligerus NRRL 3585 has been obtained by N-methyl-N'-nitro-N-nitrosoguanidine...

Utilization of ornithine and arginine as specific precursors of clavulanic acid.

Romero, J, Liras, P, Martín, J F

Ornithine and arginine (5 to 20 mM), but not glutamic acid or proline, exerted a concentration-dependent stimulatory effect on the biosynthesis of clavulanic acid in both resting-cell cultures and...

Cloning and characterization of the isopenicillin N synthase gene of Streptomyces griseus NRRL 3851 and studies of expression and complementation of the cephamycin pathway in Streptomyces clavuligerus.

García-Domínguez, M, Liras, P, Martín, J F

A gene, pcbC, encoding the isopenicillin N synthase of Streptomyces griseus NRRL 3851, has been cloned in a 6.4-kb Bg/II DNA fragment and located in an internal 1.55-kb PvuII segment by hybridization...

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

Coque, J J, Liras, P, Martín, J F

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....

Two Proteins with Ornithine Acetyltransferase Activity Show Different Functions in Streptomyces clavuligerus: Oat2 Modulates Clavulanic Acid Biosynthesis in Response to Arginine

De La Fuente, A., Martín, J. F., Rodríguez-García, A., Liras, P.

The oat2 gene, located in the clavulanic acid gene cluster in Streptomyces clavuligerus, is similar to argJ, which encodes N-acetylornithine:glutamic acid acetyltransferase activity. Purified...

New type of hexameric ornithine carbamoyltransferase with arginase activity in the cephamycin producers Streptomyces clavuligerus and Nocardia lactamdurans.

De La Fuente, J L, Martin, J F, Liras, P

The ornithine carbamoyltransferases (OTCases) from the beta-lactam-producing actinomycetes Streptomyces clavuligerus and Nocardia lactamdurans have been purified to near-homogeneity by...

Delta-1-piperideine-6-carboxylate dehydrogenase, a new enzyme that forms alpha-aminoadipate in Streptomyces clavuligerus and other cephamycin C-producing actinomycetes.

De La Fuente, J L, Rumbero, A, Martín, J F, Liras, P

Delta-1-Piperideine-6-carboxylate (P6C) dehydrogenase activity, which catalyses the conversion of P6C into alpha-aminoadipic acid, has been studied in the cephamycin C producer Streptomyces...