The purpose of the present study was to evaluate the usefulness of rpoB-PCR assay and concentration flurochrome (CF) staining against culture for direct detection of mycobacteria sp in respiratory specimen amongsymptomatic patients. Of the 900 specimens 52 were culture positive with Löwenstein-Jensen Medium (LJM). Of the 52 culture positive samples, 48 were positive by rpoB-PCR (sensitivity 92....

Rickettsiae are gram-negative, obligately intracellular bacteria responsible for arthropod-borne spotted fevers and typhus. Experimental studies have delineated a cluster of naturally rifampin-resistant spotted fever group species. We sequenced the 4, 122- to 4,125-bp RNA polymerase beta-subunit-encoding gene (rpoB) from typhus and spotted fever group representatives and obtained partial sequen...

The Escherichia coli GroP- phenotype, associated with some dnaB mutants and measured as a decreased ability to plate lambda bacteriophage, was altered by some rpoB mutations. The rpoB effect showed an allele specificity. The participation both of dnaB and of lambda P alleles in the GroP- phenotype was also allele specific. It was concluded that RNA polymerase, dnaB protein, and lambda P protein...

A cloned rpoB gene, specifying an apparently mutant RNA polymerase beta subunit, protected Escherichia coli against the cytocidal effects of the E3 protein of bacteriophage SPO1, suggesting that RNA polymerase is the primary cellular target of the E3 protein. Two segments of the wild-type E. coli genome, one of which specifies a suppressor of dnaK mutations, and thus, possibly, a molecular chap...

Resistance determinants that interfere with normal physiological processes in the bacterial cell usually cause a reduction in biological fitness. Fitness assays revealed that 17 of 18 in vitro-selected chromosomal mutations within the rpoB gene accounting for rifampin resistance in Staphylococcus aureus were associated with a reduction in the level of fitness. There was no obvious correlation b...

This study was designed with the aim of exploring efficacy RNA polymerase beta subunit, rpoB gene analysis for identification streptomycetes. A characteristic marine environment distinguished by their content streptomycetes were targeted, and two organisms genus Streptomyces isolated in Saudi Arabia. The spp., named isolates EH1 EH2 subjected to regular phenotypic characterization including mor...

We investigated the size and continuity of DNA segments integrated in Bacillus subtilis transformation. We transformed B. subtilis strain 1A2 toward rifampicin resistance (coded by rpoB) with genomic DNA and with a PCR-amplified 3.4-kb segment of the rpoB gene from several donors. Restriction analysis showed that smaller lengths of donor DNA integrated into the chromosome with transformation by...

Nucleocidin, a fairly broad antibacterial and trypanocidal agent produced by Streptomyces calvus, has the unique structure of 40-fluoro-50-O-sulfamoyl adenosine. This nucleoside antibiotic has been a target for organic synthesis in past decades; however, microbial large-scale production has not been established due to low yield and poor reproducibility. To activate the dormant secondary metabol...

The phytopathogenic genus Xanthomonas comprises numerous species and pathovars described primarily on their host and tissue specificities. Stenotrophomonas maltophilia , which is non-phytopathogenic and taxonomically closely related to Xanthomonas , has undergone several classifications from Pseudomonas to Xanthomonas and finally to Stenotrophomonas . In this study, we have investigated the phy...

The rpoB gene mutations in a 69-bp region of the gene, resulting in resistance to rifampin, were used to discriminate between Mycobacterium tuberculosis IS6110 fingerprint subclusters. These subclusters exhibited identical IS6110 fragments or had one or two additional fragments. In the two major subclusters all the analyzed strains have the same variant rpoB allele but are different from each o...