Skip to main content
NCBI home page
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1996 May;178(10):2775–2784. doi: 10.1128/jb.178.10.2775-2784.1996

Analysis of 0.5-kilobase-pair repeats in the Mycoplasma hominis lmp gene system and identification of gene products.

S A Ladefoged 1, L T Jensen 1, B Brock 1, S Birkelund 1, G Christiansen 1
PMCID: PMC178011  PMID: 8631664

Abstract

Mycoplasma hominis, an opportunistic pathogenic bacterium of humans, has a small genome of 700 kb. Despite this, multiple copies of gene sequences with similarities to the structural gene (lmp1) of a 135-kDa surface-located membrane protein (Lmp1) have been identified on the genome of M. hominis PG21 (lmp2, lmp3, and lmp4). The distance between the lmp1-lmp2 region and the lmp3-lmp4 region was more than 110 kb. lmp3-lmp4 of M. hominis PG21 was sequenced and found to contain two putative genes. The gene region of 6.5 kb contained a 5' unique region and a 3' unique region separated by 9 0.5-kb repeats with 51 to 90% similarity to 10 similar repeats found in the lmp1-lmp2 region. The 0.5-kb DNA repeats thus comprised about 1% of the entire genome. In both regions, a base change in one of the repeats gave rise to a stop codon, and thereby lmp2 and lmp4 occurred. By PCR amplification of reverse-transcriptase-generated cDNA it was shown that all four genes were transcribed. By use of Lmp-specific antibodies we showed that both lmp1 and lmp3 were translated into proteins (Lmp1 and Lmp3). Each of the four lmp genes represented by their unique cloned segments was used as a probe to analyze the presence, distribution, and organization of the genes within the genome in 13 M. hominis isolates. The repetitive element was detected at one or two locations on the chromosome for all isolates. The lmp3-specific element was present in all isolates, and lmp1- and lmp2-specific elements were present in all but one isolate. The lmp4-specific element was present in about half the isolates tested. For five M. hominis isolates the chromosomal location of the lmp genes was mapped.

Full Text

The Full Text of this article is available as a PDF (788.2 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Andersen H., Birkelund S., Christiansen G., Freundt E. A. Electrophoretic analysis of proteins from Mycoplasma hominis strains detected by SDS-PAGE, two-dimensional gel electrophoresis and immunoblotting. J Gen Microbiol. 1987 Jan;133(1):181–191. doi: 10.1099/00221287-133-1-181. [DOI] [PubMed] [Google Scholar]
  2. Bak A. L., Black F. T., Christiansen C., Freundt E. A. Genome size of mycoplasmal DNA. Nature. 1969 Dec 20;224(5225):1209–1210. doi: 10.1038/2241209a0. [DOI] [PubMed] [Google Scholar]
  3. Cassell G. H., Watson H. L., Blalock D. K., Horowitz S. A., Duffy L. B. Protein antigens of genital mycoplasmas. Rev Infect Dis. 1988 Jul-Aug;10 (Suppl 2):S391–S398. doi: 10.1093/cid/10.supplement_2.s391. [DOI] [PubMed] [Google Scholar]
  4. Chomczynski P., Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal Biochem. 1987 Apr;162(1):156–159. doi: 10.1006/abio.1987.9999. [DOI] [PubMed] [Google Scholar]
  5. Cleavinger C. M., Kim M. F., Im J. H., Wise K. S. Identification of mycoplasma membrane proteins by systematic Tn phoA mutagenesis of a recombinant library. Mol Microbiol. 1995 Oct;18(2):283–293. doi: 10.1111/j.1365-2958.1995.mmi_18020283.x. [DOI] [PubMed] [Google Scholar]
  6. Dallo S. F., Baseman J. B. Adhesin gene of Mycoplasma genitalium exists as multiple copies. Microb Pathog. 1991 Jun;10(6):475–480. doi: 10.1016/0882-4010(91)90113-o. [DOI] [PubMed] [Google Scholar]
  7. Devereux J., Haeberli P., Smithies O. A comprehensive set of sequence analysis programs for the VAX. Nucleic Acids Res. 1984 Jan 11;12(1 Pt 1):387–395. doi: 10.1093/nar/12.1part1.387. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. DiRita V. J., Mekalanos J. J. Genetic regulation of bacterial virulence. Annu Rev Genet. 1989;23:455–482. doi: 10.1146/annurev.ge.23.120189.002323. [DOI] [PubMed] [Google Scholar]
  9. Finlay B. B., Falkow S. Common themes in microbial pathogenicity. Microbiol Rev. 1989 Jun;53(2):210–230. doi: 10.1128/mr.53.2.210-230.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Fischetti V. A. Streptococcal M protein. Sci Am. 1991 Jun;264(6):58–65. doi: 10.1038/scientificamerican0691-58. [DOI] [PubMed] [Google Scholar]
  11. Jensen L. T., Ladefoged S., Birkelund S., Christiansen G. Selection of Mycoplasma hominis PG21 deletion mutants by cultivation in the presence of monoclonal antibody 552. Infect Immun. 1995 Sep;63(9):3336–3347. doi: 10.1128/iai.63.9.3336-3347.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Ladefoged S. A., Birkelund S., Hauge S., Brock B., Jensen L. T., Christiansen G. A 135-kilodalton surface antigen of Mycoplasma hominis PG21 contains multiple directly repeated sequences. Infect Immun. 1995 Jan;63(1):212–223. doi: 10.1128/iai.63.1.212-223.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Ladefoged S. A., Christiansen G. Analysis of the nucleotide sequence of the Mycoplasma hominis tuf gene and its flanking region. FEMS Microbiol Lett. 1991 Apr 15;63(2-3):133–139. doi: 10.1016/0378-1097(91)90075-l. [DOI] [PubMed] [Google Scholar]
  14. Ladefoged S. A., Christiansen G. Physical and genetic mapping of the genomes of five Mycoplasma hominis strains by pulsed-field gel electrophoresis. J Bacteriol. 1992 Apr;174(7):2199–2207. doi: 10.1128/jb.174.7.2199-2207.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Markham P. F., Glew M. D., Sykes J. E., Bowden T. R., Pollocks T. D., Browning G. F., Whithear K. G., Walker I. D. The organisation of the multigene family which encodes the major cell surface protein, pMGA, of Mycoplasma gallisepticum. FEBS Lett. 1994 Oct 3;352(3):347–352. doi: 10.1016/0014-5793(94)00991-0. [DOI] [PubMed] [Google Scholar]
  16. Meyer T. F., Gibbs C. P., Haas R. Variation and control of protein expression in Neisseria. Annu Rev Microbiol. 1990;44:451–477. doi: 10.1146/annurev.mi.44.100190.002315. [DOI] [PubMed] [Google Scholar]
  17. Neimark H. C. Division of mycoplasmas into subgroups. J Gen Microbiol. 1970 Oct;63(2):249–263. doi: 10.1099/00221287-63-2-249. [DOI] [PubMed] [Google Scholar]
  18. Notarnicola S. M., McIntosh M. A., Wise K. S. Multiple translational products from a Mycoplasma hyorhinis gene expressed in Escherichia coli. J Bacteriol. 1990 Jun;172(6):2986–2995. doi: 10.1128/jb.172.6.2986-2995.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Pyle L. E., Corcoran L. N., Cocks B. G., Bergemann A. D., Whitley J. C., Finch L. R. Pulsed-field electrophoresis indicates larger-than-expected sizes for mycoplasma genomes. Nucleic Acids Res. 1988 Jul 11;16(13):6015–6025. doi: 10.1093/nar/16.13.6015. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Ruland K., Wenzel R., Herrmann R. Analysis of three different repeated DNA elements present in the P1 operon of Mycoplasma pneumoniae: size, number and distribution on the genome. Nucleic Acids Res. 1990 Nov 11;18(21):6311–6317. doi: 10.1093/nar/18.21.6311. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Seifert H. S., So M. Genetic mechanisms of bacterial antigenic variation. Microbiol Rev. 1988 Sep;52(3):327–336. doi: 10.1128/mr.52.3.327-336.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Su C. J., Chavoya A., Baseman J. B. Regions of Mycoplasma pneumoniae cytadhesin P1 structural gene exist as multiple copies. Infect Immun. 1988 Dec;56(12):3157–3161. doi: 10.1128/iai.56.12.3157-3161.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Su C. J., Dallo S. F., Chavoya A., Baseman J. B. Possible origin of sequence divergence in the P1 cytadhesin gene of Mycoplasma pneumoniae. Infect Immun. 1993 Mar;61(3):816–822. doi: 10.1128/iai.61.3.816-822.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Sutcliffe I. C., Russell R. R. Lipoproteins of gram-positive bacteria. J Bacteriol. 1995 Mar;177(5):1123–1128. doi: 10.1128/jb.177.5.1123-1128.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Wang Y. Double-stranded DNA sequencing with T7 polymerase. Biotechniques. 1988 Oct;6(9):843–845. [PubMed] [Google Scholar]
  26. Woese C. R., Stackebrandt E., Ludwig W. What are mycoplasmas: the relationship of tempo and mode in bacterial evolution. J Mol Evol. 1984;21(4):305–316. doi: 10.1007/BF02115648. [DOI] [PubMed] [Google Scholar]
  27. Yogev D., Rosengarten R., Watson-McKown R., Wise K. S. Molecular basis of Mycoplasma surface antigenic variation: a novel set of divergent genes undergo spontaneous mutation of periodic coding regions and 5' regulatory sequences. EMBO J. 1991 Dec;10(13):4069–4079. doi: 10.1002/j.1460-2075.1991.tb04983.x. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES