The nucleotide sequence of a methyl-accepting chemotaxis protein gene,
mcpA, from Treponema denticola has been determined. The mcpA gene enc
odes a 729-amino acid protein whose deduced amino acid sequence has si
gnificant homology with several bacterial MCPs. T. denticola McpA cont
ains two N-terminal transmembrane regions and two C-terminal putative
methylation sequences that art separated by a highly conserved signali
ng domain. The organization of these structural features is characteri
stic of MCPs. The observed molecular mass of the in vitro synthesized
McpA (76.0 kDa) correlates with the predicted molecular mass of the pr
otein (80.1 kDa).