Antigenic and genetic characterisation of lipoprotein lppC from Mycoplasma mycoides subsp. mycoides SC

Abstract

-Lipoprotein LppC, an immunodominant antigen, and its corresponding gene lppC were characterised in Mycoplasma mycoides subspecies mycoides small colony (SC) type, the etiological agent of contagious bovine pleuropneumonia (CBPP). The lppC gene was found in the type strain of M. mycoides subsp. mycoides SC and in field strains isolated in Europe, Africa, and Australia, as well as in vaccine strains. Southern blot analysis indicated the presence of at least four copies of lppC in the genome of M. mycoides subsp. mycoides SC, of which only one seems to be functional. Genes homologous to lppC have also been detected in closely related mycoplasmas such as M. mycoides subsp. mycoides large colony (LC) type and in M. sp. bovine group 7. LppC is encoded as a precursor with a consensus sequence for a prokaryotic signal peptidase II. The amino acid sequence of LppC and its precursor showed similarity to both LppB (at the N-terminal domain) and LppQ (at the C-terminal domain), two lipoproteins described previously in M. mycoides subsp. mycoides SC. The N-terminal domain of the mature LppC seems to be surface exposed. The C-terminal domain presented an integral membrane structure made up of five repeated units, rich in hydrophobic and aromatic amino acids, which may have pore forming potential in the mycoplasmal membrane. A recombinant peptide representing the N-terminal half of LppC was obtained following cloning in vector pETHIS-1 and expression in Escherichia coli hosts. The recombinant protein was used on immunoblots for serological analysis of sera from cattle that were naturally or experimentally infected with M. mycoides subsp. mycoides SC.Mycoplasma mycoides subsp. mycoides SC / contagious bovine pleuropneumonia / multiple copy gene / antigenic protein / lipoprotein

A Metabolic Enzyme as a Primary Virulence Factor ofMycoplasma mycoidessubsp.mycoidesSmall Colony

“…Protein concentrations were determined using the method of Bradford (12). Monospecific rabbit serum directed against lipoprotein LppC has been previously described (37).…”

“…Purified Fab fragments from polyclonal IgG directed against the membrane lipoprotein LppC of M. mycoides subsp. mycoides SC were used as a control since LppC is not correlated to the glycerol metabolism (37). In order to determine whether Nucleotide sequence accession numbers.…”

Protein-Specific Analysis of Humoral Immune Responses in a Clinical Trial for Vaccines against Contagious Bovine Pleuropneumonia

“…Subunit vaccines are still desired for CBPP prevention (10), and possible components can be proteins of known pathogenicity mechanisms, as recently reviewed (30). Among these are the well-characterized lipoproteins LppA (6), LppB (38), LppC (31), and LppQ (1) and the variable surface protein Vmm (29). LppQ is the predominant antigen during infection in cattle (3) and has been subcloned to develop an enzyme-linked immunosorbent assay (ELISA) for CBPP diagnostics (5).…”

Multiplex Screening of Surface Proteins from Mycoplasma mycoides subsp. mycoides Small Colony for an Antigen Cocktail Enzyme-Linked Immunosorbent Assay

“…In sub-Saharan Africa, where the disease is endemic, this stamping-out procedure is not economically feasible. Vaccination is a better option for these countries, although existing vaccines so far give insufficient immunity and severe side effects (23). One of the main challenges within CBPP control is diagnosis of the subacute and chronic phases of the disease (14,22).…”

“…Methods including PCR have been shown to be successful (21) but put high demands on sampling procedures. Surface lipoproteins are of high interest both for diagnostic purposes and for studies regarding the pathogenicity of the bacterium (23). To date, only a few of the surface lipoproteins from M. mycoides SC have been studied thoroughly.…”