title: Beta-lactamase genes of Streptomyces badius, Streptomyces cacaoi and Streptomyces fradiae: cloning and expression in Streptomyces lividans.
abstract: Genes encoding extracellular beta-lactamases (EC 3.5.2.6) of Gram-positive Streptomyces badius, Streptomyces cacaoi and Streptomyces fradiae have been cloned into Streptomyces lividans. The beta-lactamase gene of S. badius was initially isolated on a 7 kb BamHI fragment and further located on a 1300 bp DNA segment. An 11 kb BamHI fragment was isolated encompassing the S. cacaoi beta-lactamase gene, which was subcloned to a 1250 bp DNA fragment. The beta-lactamase gene of S. fradiae was cloned on an 8 kb BamHI fragment and mapped to a 4 kb DNA segment. Each of the three BamHI fragments encompassing the beta-lactamase genes hybridized to a BamHI fragment of the corresponding size in chromosomal DNA from the respective strain used for cloning. The activities of the three beta-lactamases were predominantly found to be extracellular in the S. lividans recombinants. The S. badius and S. cacaoi beta-lactamases exhibited a 10-100-times lower activity in S. lividans, whereas the S. fradiae beta-lactamase showed an approximately 10-fold higher activity in the cloned state, compared with the activities found in the original strains.
authors.affiliation: Department of Cell and Microbiology, National Defence Research Institute, Umeå, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Jaurin
authors.forename: M
authors.initials: M
authors.lastname: Forsman
authors.forename: B
authors.initials: B
authors.lastname: Häggström
mesh_terms: D001692:Biological Transport; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D004269:DNA, Bacterial / Q000235:genetics; D005110:Extracellular Space / Q000201:enzymology; D005786:Gene Expression Regulation; D005798:Genes, Bacterial; D013045:Species Specificity; D013302:Streptomyces / Q000201:enzymology / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; D004262:DNA Restriction Enzymes; D001618:beta-Lactamases