Immunological and Biochemical Characterization of Membrane Proteins

Membrane proteins of mycoplasmas assume particular significance in investigations of the pathogenesis of disease. They are involved in adhesion to, and probably in other interactions with, the cells of the target tissues of the host (1 –5 ). They are frequently significant antigens in the immune response (4 –7 ), and in some cases have been observed to undergo high-frequency size and/or phase variation (8 –13 ). In addition, many membrane proteins are also important in metabolic pathways, including transmembrane transport (14 ). The significance of future research on membrane proteins of mycoplasmas has been recently highlighted by the completion of the genomic sequences of Mycoplasma genitalium and Mycoplasma pneumoniae (15 ,16 ). In both species, the products of a number of open reading frames could not be assigned a function by comparison to known prokaryotic genes. The vast majority of these unassigned products were putative membrane proteins.