title: Diversity of retron elements in a population of rhizobia and other gram-negative bacteria.
abstract: Genetic elements called retrons reside on the chromosome of Escherichia coli and the myxobacteria and represent the first reverse transcriptase-encoding element to be found in a prokaryotic cell. All known retrons produce a functionally obscure RNA-DNA satellite molecule called multicopy single-stranded DNA (msDNA). We report here the presence of msDNA-producing retron elements in a number of new bacterial groups, including strains of the genera Proteus, Klebsiella, Salmonella, Nannocystis, Rhizobium, and Bradyrhizobium. Among a population of 63 rhizobia strains, only 16% contain a retron element. The rhizobia retrons appear to be heterogeneous in nucleotide sequence and show little similarity to previously studied retrons of E. coli and the myxobacteria.
authors.affiliation: Department of Microbiology, University of Tennessee, Knoxville 37996-0845.
authors.forename: S A
authors.initials: SA
authors.lastname: Rice
authors.forename: J
authors.initials: J
authors.lastname: Bieber
authors.forename: J Y
authors.initials: JY
authors.lastname: Chun
authors.forename: G
authors.initials: G
authors.lastname: Stacey
authors.forename: B C
authors.initials: BC
authors.lastname: Lampson
mesh_terms: D004277:DNA, Single-Stranded / Q000235:genetics*; D006090:Gram-Negative Bacteria / Q000201:enzymology / Q000235:genetics*; D007709:Klebsiella / Q000201:enzymology / Q000235:genetics; D009692:Nucleic Acid Heteroduplexes / Q000235:genetics*; D011511:Proteus / Q000201:enzymology / Q000235:genetics; D012194:RNA-Directed DNA Polymerase / Q000235:genetics*; D012230:Rhizobiaceae / Q000201:enzymology / Q000235:genetics*; D012475:Salmonella / Q000201:enzymology / Q000235:genetics; D013045:Species Specificity
chemical_list: D004277:DNA, Single-Stranded; D009692:Nucleic Acid Heteroduplexes; D012194:RNA-Directed DNA Polymerase