Assessment of PCR for routine identification of species of the Mycoplasma mycoides cluster in ruminantsDominique Le Granda, Estelle Sarasb, Denis Blondb, Michel Solsonab and François Poumaratb
a UMR Mycoplasmoses des Ruminants, Pathologie du Bétail, École Nationale Vétérinaire de Lyon, 1 avenue Bourgelat, 69280 Marcy-l'Étoile, France
b UMR Mycoplasmoses des Ruminants, AFSSA Site de Lyon, 31 avenue Tony Garnier, 69364 Lyon Cedex 07, France
(Received 15 December 2003; accepted 13 May 2004)
Abstract - DNA amplification techniques offer considerable promise for the identification of Mycoplasma mycoides cluster members. They avoid antigenic cross-reactivity and variability that hamper serological methods. Many sets of primers, specific of these different members and of Mycoplasma putrefaciens, have been proposed. To assess the reliability of some of these PCR tests in routine laboratory diagnostic use, 230 field strains supposed to belong to this group were simultaneously identified by PCR and an antigenic method. The results were well correlated to antigenic identification for M. putrefaciens, but PCR failed to identify respectively 74% and 52% of M. mycoides subsp. mycoides Large Colony type and M. capricolum subsp. capricolum strains. Any identification of M. mycoides subsp. mycoides Small Colony type must be confirmed by two different tests. Difficulties in defining the M. species bovine serogroup 7 were also encountered with both the PCR and immunological methods. The occurrence of putative variable antigen(s) on the mycoplasma surface may explain part of the identification difficulties encountered with the immunological methods.
Key words: Mycoplasma mycoides cluster / PCR / ruminants / identification / variable antigen
Corresponding author: François Poumarat firstname.lastname@example.org
© INRA, EDP Sciences 2004