Summary of report: Determination of the genomic sequence of Mycoplasma gallisepticum

|| Home || SEARCH|| Contact || Free Research Publications || Eshop || Privacy Statement ||

Download full report (276k - HINT: right click and save the file to your hard disk before opening)
This report is available only in htis download version

Determination of the genomic sequence of Mycoplasma gallisepticum

by Dr GF Browning and Dr PF Markham

December 2004

RIRDC Publication No 04/140 RIRDC Project No UM-45J

Executive Summary

Although mycoplasmosis has been controlled with the current generation of vaccines, future control programs may need to focus on improvements in these vaccines so that they are compatible with eradication or so that they are effective in different strains of bird. In the last few years a number of human pathogens have been fully sequenced, including four human mycoplasmas, and parallel information for avian mycoplasmas would enable rapid application of findings on human mycoplasma genes to improving avian mycoplasma vaccines. The University of Melbourne was invited to participate in a project to sequence the Mycoplasma gallisepticum genome and subsequently to collaboratively examine the basis of virulence, with the ultimate aim of developing defined third generation vaccines. Involvement in this collaborative exercise has ensured early access to this data, thus enhancing current research programs on mycoplasmosis in Australia. The project presented a unique opportunity to obtain this data at cost, using highly specialised facilities developed in the USA for sequencing large genomes. The strain chosen for sequencing was the standard virulent strain used for challenge trials in the USA.

The genome of the virulent R strain of M. gallisepticum was sheared into fragments, which were then randomly cloned and sequenced. The genome was found to be 996,422 base pairs. It was predicted to contain 742 genes encoding proteins and some function could be assigned to 469 of these. A further 150 predicted genes are similar to genes in other bacterial species and 123 are thus far unique to Mycoplasma gallisepticum. The vlhA gene family, which is thought to play a key role in chronicity of mycoplasmosis in birds, contains 43 genes distributed among five loci containing 8, 2, 9, 12 and 12 genes and comprised 10.4% (103 kb) of the total genome. A total of 80 genes are predicted to encode lipoproteins which are likely to be involved intimately in interactions with the host and a number of other putative virulence factors have been identified. These data lay a strong basis for ongoing studies on the basis of virulence in M. gallisepticum. The data are publicly available at http://cevr.uconn.edu and through Genbank.

Links

Last updated: 19 December 2004Copyright RIRDC
http://www.rirdc.gov.au/reports/CME/04-140sum.html