The Rhizobium leguminosarum h o s t-range (Sym) plasmid, pJB5JI, is a 130 Mdal conjugative plasmid which carries the genes for host-specificity (i.e., for peas) and some of the genes for ni trogen-fixation. We have t ransferred plasmid pJB5JI into different species of Rhizobium and examined the symbiotic propert ies of the result ing transconjugants. The donor strain R. leguminosarum 6015 (pJB5...

After enrichment by a tetracycline suicide under conditions nonpermissive for the growth of mutants defective in photosynthesis, colonies were screened for enhanced fluorescence in near-infrared light by using high-speed infrared photography. Twenty mutants were isolated, and the chromatophore membranes were analyzed by a new, rapid microprocedure that revealed many different phenotypes among t...

BACKGROUND & OBJECTIVES The multiple drug resistance (MDR) is a serious health problem and major challenge to the global drug discovery programmes. Most of the genetic determinants that confer resistance to antibiotics are located on R-plasmids in bacteria. The present investigation was undertaken to investigate the ability of organic extract of the fruits of Helicteres isora to cure R-plasmids...

Multi-antimicrobial-resistant Salmonella enterica strains frequently carry resistance genes on plasmids. Recent studies focus heavily on large conjugative plasmids, and the role that small plasmids play in resistance gene transfer is largely unknown. To expand our previous studies in assessing the prevalence of the isolates harboring ColE1-like plasmids carrying the aph gene responsible for kan...

1Department of Pathology and Microbiology, Faculty of Medicine, University of Jordan, Amman, Jordan. Received: 27/01/03; accepted: 06/05/03 ABSTRACT We investigated antimicrobial resistance patterns and plasmid profiles of uropathogenic Escherichia coli isolates from inpatients and outpatients at Jordan University Hospital in 2000 and 2001. E. coli accounted for 32.4% and 37.4% of all isolates ...

Different strains and species of the soil phytopathogen Agrobacterium possess the ability to transfer and integrate a segment of DNA (T-DNA) into the genome of their eukaryotic hosts, which is mainly mediated by a set of virulence (vir) genes located on the bacterial Ti-plasmid that also contains the T-DNA. To date, Agrobacterium is considered to be unique in its capacity to mediate genetic tra...

A 6.1 kb plasmid from the Lactococcus lactis subsp. cremoris strain UC509.9, named pCIS3, was found to mediate a restriction/modification (R/M) phenotype. Nucleotide sequence analysis of pCIS3 revealed the presence of an hsdS gene, typical of type I R/M systems. The presence of this plasmid resulted in a 10(4)-fold reduction in the efficiency of plating (e.o.p.) of unmodified phage. In addition...

Rhizobium etli type strain CFN42 contains six plasmids. We analyzed the distribution of genetic markers from some of these plasmids in bean-nodulating strains belonging to different species (Rhizobium etli, Rhizobium gallicum, Rhizobium giardinii, Rhizobium leguminosarum, and Sinorhizobium fredii). Our results indicate that independent of geographic origin, R. etli strains usually share not onl...

Inhalation of the facultative intracellular bacterium, Rhodococcus equi, can result in a severe pyogranulomatous pneumonia in young horses and immunocompromised people. This organism is able to resist innate immune defenses and establish residence within the intracellular environment of the alveolar macrophage. Virulence determinants of R. equi have yet to be fully elucidated, but all equine is...

Rickettsia felis (Alphaproteobacteria: Rickettsiales) is the causative agent of an emerging flea-borne rickettsiosis with worldwide occurrence. Originally described from the cat flea, Ctenocephalides felis, recent reports have identified R. felis from other flea species, as well as other insects and ticks. This diverse host range for R. felis may indicate an underlying genetic variability assoc...