Sequencing analysis reveals a unique gene organization in the gyrB region of Mycoplasma hominis

Ladefoged, Søren; Christiansen, Gunna

doi:10.1128/jb.176.18.5835-5842.1994

Cited by 26 publications

(25 citation statements)

References 32 publications

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“…AY819796 and AY819797, respectively. QRDR sequences of M. synoviae were compared to homologous sequences of M. hominis [4,6,24], M. pulmonis [8], M. gallisepticum [28] and E. coli [40].…”

Section: Nucleotide Sequence Accession Numbersmentioning

confidence: 99%

Persistence of Mycoplasma synoviae in hens after two enrofloxacin treatments and detection of mutations in the parC gene

et al. 2006

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-The ability of Mycoplasma synoviae, an avian pathogen, to persist despite fluoroquinolone treatments was investigated in hens. Groups of Mycoplasma-free hens were experimentally infected with the M. synoviae 317 strain and treated twice with enrofloxacin at the therapeutic dose. The results show that the two treatments did not have any influence on this strain of M. synoviae recovery from tracheal swabs. Mycoplasmas were isolated from tracheal swab cultures, but not from inner organs such as the liver or spleen, suggesting that this strain of M. synoviae was not able to cross the mucosal barrier to disseminate throughout the host. A significant increase of the resistance level to enrofloxacin of five re-isolated mycoplasma clones, was observed after the second treatment. This increase was associated in two clones to a Ser81→Pro substitution, found in the ParC quinolone-resistance determining region (QRDR) of DNA topoisomerase IV. This is the first time that a mutation in a gene coding for topoisomerase IV is described in M. synoviae after in vivo enrofloxacin treatments in experimentally infected hens.Mycoplasma synoviae / fluoroquinolone / persistence / topoisomerase / poultry

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“…AY819796 and AY819797, respectively. QRDR sequences of M. synoviae were compared to homologous sequences of M. hominis [4,6,24], M. pulmonis [8], M. gallisepticum [28] and E. coli [40].…”

Section: Nucleotide Sequence Accession Numbersmentioning

confidence: 99%

Persistence of Mycoplasma synoviae in hens after two enrofloxacin treatments and detection of mutations in the parC gene

et al. 2006

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“…In the genome of some mycoplasmas, the gyrA and gyrB genes were identified (1,3,4,13,26), and parC and parE, the topo IV genes, were identified in M. genitalium (2). Therefore, it can be assumed that these genes are also present in the species examined in this study.…”

Section: Discussionmentioning

confidence: 90%

“…The genes, gyrA and gyrB, that encode both subunits of DNA gyrase were identified in Mycoplasma pneumoniae (3). The gyrB gene was identified in Mycoplasma hominis (13), Mycoplasma genitalium (1), Mycoplasma capricolum (26), and Mycoplasma gallisepticum (4). In addition, the genes encoding topo IV were identified in M. genitalium (2).…”

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confidence: 99%

Characterization of DNA topoisomerase activity in two strains of Mycoplasma fermentans and in Mycoplasma pirum

1997

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DNA topoisomerases (topos) are essential enzymes that participate in many cellular processes involving DNA. The presence of the DNA-gyrase genes in various mycoplasmas has been reported elsewhere. However, the characterization of DNA topo activity in mycoplasmas has not been previously undertaken. In this study, we characterized the topo activity in extracts of Mycoplasma fermentans K7 and incognitus and in Mycoplasma pirum, as well as in partially purified extract of M. fermentans K7. The topo activity in these microorganisms had the following properties. These results suggest that the properties of the topo enzyme in these mycoplasma species resemble those of the bacterial topo IV and the eukaryotic and the bacteriophage T4 topo II. The findings that mycoplasma topo is inhibited by both eukaryotic topo II and topo I antagonists and that m-AMSA and camptothecin inhibited the growth of M. fermentans K7 in culture support our conclusion that these mycoplasma species have topo with unique properties.

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“…A transcript of 3.2 kb had been identified previously (Ladefoged & Christiansen, 1994) using a hybridization probe (pE12H-23) derived from the 3' region of p120', which is similar to that of p220 (Fig. 2a, lane 2).…”

Section: Transcription Of the P12q Gene In M Horninismentioning

confidence: 98%

“…An open reading frame on the M. hominis chromosome (ORF445), the 3' end of which had been partly characterized previously (Ladefoged & Christiansen, 1994), was found to be similar to p220. The aim of this study was to characterize the remainder of ORF44.5 (the ~2 2 0 ' gene), the pIZO gene family in 24 M. hominis isolates, and the product of the p220' gene.…”

Section: Introductionmentioning

confidence: 99%

Mycoplasma hominis expresses two variants of a cell-surface protein, one a lipoprotein, and one not

Ladefoged¹,

Christiansen²

1998

Microbiology

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A protein similar to the previously characterized variable surface-exposed membrane protein P120 was identified (PlZO'), establishing that Mycop/asma hominis PG21 possesses a novel gene family. The gene, pIZO', was sequenced and found to have some distinctive properties including a putative start codon of GTG, rather than the common ATG codon, and a coding region with a high G+C content, characteristic of essential housekeeping genes in mycoplasmas. No sequence homology was found to known proteins. The genomic locations of the p120 and p120 genes were determined on the restriction map of five M.hominis strains by PFGE. The genes were localized in two separate regions separated by more than 6 kb. Genes as well as proteins corresponding to P120' were identified in 24/24 M. horninis isolates tested and no size variation was detected. P120' had a molecular mass of 98 kDa, 20 kDa smaller than P120 as estimated by SDS-PAGE. The protein was surface-exposed and associated with the mycoplasma membrane, but had predominantly hydrophilic characteristics upon Triton X-114 extraction. The N-terminal part of P120' had a hydrophobic leader sequence without the characteristics of a prolipoprotein. This might explain the membrane association of the protein. Unlike P120, which is frequently recognized by sera of patients seropositive for M. hominis, P120' was only rarely recognized. The conserved nature of the Pl20 gene family indicates that it has an essential, although currently unknown, function.Keywords : reiterated genes, chromosome mapping, membrane proteins, P120' protein, P120 protein INTRODUCTIONIn spite of their uniquely small chromosome (Himmelreich et al., 1996;Fraser et al., 1995;Bak et al., 1969), and consequently limited biosynthetic capability, mycoplasmas have successfully adapted to a wide range of hosts. Mycoplasmas lack a cell wall, and the surface components of the single limiting cell membrane are thus essential for host adaptation. Mycoplasma hominis is an opportunistic pathogen causing gynaecological infections, and is increasingly detected in extragenital infections (Meyer & Clough, 1993). Surface antigens of M . hominis vary considerably between isolates (Christiansen, 1992;Christiansen et al., 1994;Ladefoged et al., 1990Ladefoged et al., , 1995 Ladefoged et al., , 1996Jensen et al., 1995; The EMBL accession number for the sequence reported in this paper is Y 13476.1991b; Andersen et al., 1987). Even in isolates derived successively from a single chronically infected patient some antigenic variation was observed (Olson et al., 1991a). Three different surface-exposed membrane proteins have been characterized in detail in M. horninis. The Lmp family consists of two 135 kDa surfaceexposed proteins, Lmpl and Lmp3 (Ladefoged et al., 1995(Ladefoged et al., , 1996Jensen et al., 1995 S. A. LADEFOGED and G. C H R I S T I A N S E Ngen, identified as a lipoprotein, also shows variation in size and antigenicity between isolates (Henrich et al., 1996 ; Zhang & Wise, 1996). The size variation is caused by loss or...

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Sequencing analysis reveals a unique gene organization in the gyrB region of Mycoplasma hominis

Cited by 26 publications

References 32 publications

Persistence of Mycoplasma synoviae in hens after two enrofloxacin treatments and detection of mutations in the parC gene

Persistence of Mycoplasma synoviae in hens after two enrofloxacin treatments and detection of mutations in the parC gene

Characterization of DNA topoisomerase activity in two strains of Mycoplasma fermentans and in Mycoplasma pirum

Mycoplasma hominis expresses two variants of a cell-surface protein, one a lipoprotein, and one not

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