Biomedical subjects

R V Ferrell

Publications and source records attributed to R V Ferrell.

3 recordsLinked to original sources

PubMed1989

A Mycoplasma genetic element resembling prokaryotic insertion sequences.

Nucleotide sequence analysis of two Mycoplasma hyopneumoniae-derived copies of a repetitive genetic element revealed structural similarities to typical prokaryotic insertion sequences. This is the first such sequence identified in the class Mollicutes. The element spans approximately 1550bp, with 28bp inverted terminal repeats. Two open reading frames occur within the sequence, one potentially encoding a protein with a size-variant alpha-helical domain containing heptameric leucine periodicity. Hybridization data with several strains from each of two mycoplasma species showed that the repetitive sequence is variably distributed within the M. hyopneumoniae and Mycoplasma hyorhinis chromosomes and indicated that in some cases the repeated sequence is contained within a larger genetic element which may be the result of phage or plasmid insertion.

Amino Acid Sequence↗

PubMed1988

Reiterated DNA sequences defining genomic diversity within the species Mycoplasma hyorhinis.

Genomic restriction fragments isolated from Mycoplasma hyorhinis and Mycoplasma hyopneumoniae were shown by DNA hybridization and nucleotide sequence analyses to contain sequences common to these two species, as well as another porcine-derived mycoplasma, Mycoplasma flocculare. Intraspecies hybridization experiments using these fragments as probes indicated that the sequence is highly redundant in several strains of M. hyorhinis, but that there is diversity in the sizes of restriction fragments detected among these strains. In contrast, repetition of the sequence was limited in M. hyopneumoniae and M. flocculare, and no homologies to this repeated element were apparent in mycoplasma species isolated from animal hosts other than the swine. The reiterated sequence may reflect intraspecies genomic diversification in M. hyorhinis and its selective presence in otherwise unrelated species raises the possibility that it has been horizontally transmitted between these organisms.

Bacteriophages↗

PubMed1987

Identification of a repetitive genomic sequence that is distributed among a select group of mycoplasmas.

Homologous DNA sequences common to different Mycoplasma species were identified and isolated using interspecies DNA hybridization. Specific homologies were found in three species of porcine mycoplasmas that were not detected in species from other animal hosts. Restriction fragments bearing these common sequences were isolated from genomic libraries of M. hyorhinis and M. hyopneumoniae, and DNA sequence analysis confirmed the sequence conservation predicted from hybridization studies. Multiple homology signals were detected by probing M. hyorhinis genomic digests with the isolated restriction fragments, suggesting that these common sequences are present in many copies in that species. The repetition of this sequence is, however, more limited in the other porcine mycoplasma chromosomes.

Animals↗