Isolation and structure of a .BETA.-lactamase inhibitor from Streptomyces.

Isolation and characterization of a phage active against streptomyces griseus

The crystal structure of the beta-lactamase of Streptomyces albus G at 0.3 nm resolution.

The crystal structure of the beta-lactamase of Streptomyces albus G has been solved at 0.3 nm resolution by X-ray-diffraction methods. The enzyme is a typical two-domain protein. One domain consists of five alpha-helices, and the other is five-stranded beta-sheet with alpha-helices on both sides of the sheet. The active-site serine residue (Ser-48) is within a cleft located between the two doma...

Isolation and Identification of Streptomyces ramulosus from Soil and Determination of Antimicrobial Property of its Pigment

Background and objective: Pigment production by microorganisms is important due to more rapid growth, higher efficiency, easier extraction, and antimicrobial effects compared to other methods. The aim of the present study is to isolate and identify antibiotic pigment-producing actinomycetes from the soil of the Persian Gulf and to evaluate the antibiotic activity of their pigments in the second...

Cloning, sequencing, and site-directed mutagenesis of beta-lactamase gene from Streptomyces fradiae Y59.

The beta-lactamase gene from Streptomyces fradiae Y59 was cloned and sequenced. To determine which amino acid residues are critical in binding activity to blue dextran, chimera beta-lactamases were constructed and their binding abilities were determined. The results suggested that blue dextran binding may depend more on overall conformation of about two-thirds of the beta-lactamase molecule fro...

Isolation and expression of a novel molecular class D beta-lactamase, OXA-61, from Campylobacter jejuni.

A novel beta-lactamase gene, blaOXA-61, from Campylobacter jejuni GC015 was cloned and its nucleotide sequence determined. blaOXA-61 encodes a protein of 257 amino acids in which the active-site STFK tetrad and conserved class D beta-lactamase motifs YGN and KTG were identified. A conserved sequence upstream of blaOXA-61 is required for expression in Campylobacter.