Characterization of two in vivo-expressed methyltransferases of the Mycobacterium tuberculosis complex: antigenicity and genetic regulation.
Genome sequencing of Mycobacterium tuberculosis complex members has accelerated the search for new disease-control tools. Antigen mining is one area that has benefited enormously from access to genome data. As part of an ongoing antigen mining programme, we screened genes that were previously identified by transcriptome analysis as upregulated in response to an in vitro acid shock for their in vivo expression profile and antigenicity. We show that the genes encoding two methyltransferases, Mb1438c/Rv1403c and Mb1440c/Rv1404c, were highly upregulated in a mouse model of infection, and were antigenic in M. bovis-infected cattle. As the genes encoding these antigens were highly upregulated in vivo, we sought to define their genetic regulation. A mutant was constructed that was deleted for their putative regulator, Mb1439/Rv1404; loss of the regulator led to increased expression of the flanking methyltransferases and a defined set of distal genes. This work has therefore generated both applied and fundamental outputs, with the description of novel mycobacterial antigens that can now be moved into field trials, but also with the description of a regulatory network that is responsive to both in vivo and in vitro stimuli.
Golby
Paul
P
Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
Nunez
Javier
J
Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
Cockle
Paul J
PJ
Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
Ewer
Katie
K
Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
Logan
Karen
K
Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
Hogarth
Philip
P
Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
Vordermeier
H Martin
HM
Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
Hinds
Jason
J
Bacterial Microarray Group, Department of Cellular and Molecular Medicine, St George's Hospital Medical School, Cranmer Terrace, London SW17 0RE, UK.
Hewinson
R Glyn
RG
Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
Gordon
Stephen V
SV
Veterinary Laboratories Agency (Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
D000818:Animals; D000942:Antigens, Bacterial / Q000096:biosynthesis* / Q000276:immunology*; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000276:immunology; D002417:Cattle; D005260:Female; D017353:Gene Deletion; D020869:Gene Expression Profiling; D005809:Genes, Regulator; D008780:Methyltransferases / Q000096:biosynthesis* / Q000276:immunology*; D051379:Mice; D016254:Mutagenesis, Insertional; D009163:Mycobacterium bovis / Q000201:enzymology* / Q000276:immunology; D009169:Mycobacterium tuberculosis / Q000201:enzymology* / Q000276:immunology; D020411:Oligonucleotide Array Sequence Analysis; D014376:Tuberculosis / Q000276:immunology; D014380:Tuberculosis, Bovine / Q000276:immunology; D015854:Up-Regulation
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D008780:Methyltransferases