Both kanamycin A and kanamycin B, antibiotic components produced by Streptomyces kanamyceticus, have medical value. Two different pathways for kanamycin biosynthesis have been reported by two research groups. In this study, to obtain an optimal kanamycin A-producing strain and a kanamycin B-high-yield strain, we first examined the native kanamycin biosynthetic pathway in vivo. Based on the prop...

Article history: Received on: 04/02/2014 Revised on: 28/02/2014 Accepted on: 12/03/2014 Available online: 28/07/2014 ATPbinding cassette (ABC) transporters are characterized as multi drug resistant transporters utilizing ATP hydrolysis. The SCO5113 (GeneID: 1100554) encoding a multidrug resistance ABC transporter in Streptomyces coelicolor was expressed in E.coli BL21 (DE3) plysS, using pET 21 ...

In bacteria, the first reaction of the tryptophan biosynthetic pathway involves the conversion of chorismate and glutamine to anthranilate by the action of anthranilate synthase, which is composed of the alpha (trpE gene product) and beta (trpG gene product) subunits. In this study, the tryptophan biosynthetic gene trpE of the spirochaete Leptospira meyeri was interrupted by a kanamycin-resista...

Oligoribonuclease, a 3'-to-5' exoribonuclease specific for small oligoribonucleotides, was purified to homogeneity from extracts of Escherichia coli. The purified protein is an alpha2 dimer of 40 kDa. NH2-terminal sequence analysis of the protein identified the gene encoding oligoribonuclease as yjeR (o204a), a previously reported open reading frame located at 94 min on the E. coli chromosome. ...

It has been reported that Neisseria gonorrhoeae possesses a very high level of catalase activity, but the regulation of catalase expression has not been investigated extensively. In Escherichia coli and Salmonella enterica serovar Typhimurium, it has been demonstrated that OxyR is a positive regulator of hydrogen peroxide-inducible genes, including the gene encoding catalase. The oxyR gene from...

A kanamycin-producing strain, Streptomyces kanamyceticus ISP5500, is resistant to kanamycin. A kanamycin resistance determinant was cloned from S. kanamyceticus into Streptomyces lividans 1326, using the plasmid vector pIJ702. The resulting plasmid, pMCP5, could also transform Streptomyces lavendulae S985 and Streptomyces parvulus 2283 to kanamycin resistance. Transformants carrying pMCP5 were ...

We have constructed new yeast vectors for targeted integration of desired sequences at the Saccharomyces cerevisiae HO locus. Insertion at HO has been shown to have no effect on yeast growth, and thus these integrations should be neutral. One vector contains the KanMX selectable marker, and integrants can be selected by resistance to G418. The other vector contains the hisG-URA3-hisG cassette, ...

Complete genome sequences are now available for many bacterial species that lack sophisticated genetic tools. We describe the development of a broad-host-range cre-lox system that allows antibiotic marker recycling in a variety of gram-negative bacteria. This system consists of an allelic exchange vector bearing a kanamycin cassette flanked by loxP sites and a tetracycline-resistant IncP plasmi...

We have investigated the use of a natural transformation protocol to introduce mutations into Actinobacillus pleuropneumoniae serotypes 1 and 5b. For both strains tested, we recovered 1 in 10(8) transformants during culture in rich medium, a result that was independent of the growth phase. This low frequency of transformation of A. pleuropneumoniae did not increase when bacteria were grown unde...