The characterization of Mycoplasma synoviae EF-Tu protein and proteins involved in hemadherence and their N-terminal amino acid sequences

An abundant cytoplasmic 43-kDa protein from Mycoplasma synoviae, a major pa thogen from poultry, was identified as elongation factor Tu. The N-terminal amino acid sequence (AKLDFDRSKEHVNVGTIGHV) has 90% identity with the seque nce of the Mycoplasma hominis elongation factor Tu protein. Monoclonal anti bodies reacting with the M. synoviae elongation factor Tu protein also reac ted with 43-kDa proteins from the avian Mycoplasma species Mycoplasma galli narum, Mycoplasma gallinaceum, Mycoplasma pullorum, Mycoplasma cloacale, My coplasma iners and Mycoplasma meleagridis, but not with the proteins from M ycoplasma gallisepticum, Mycoplasma imitans or Mycoplasma iowae. In additio n, two groups of phase variable integral membrane proteins, pMSA and pMSB, associated with hemadherence and pathogenicity of M, synoviae strains AAY-4 and ULB 925 were identified. The cleavage of a larger hemagglutinating pro tein encoded by a gene homologous to the vlhA gene of M. synoviae generates pMSB(1) and pMSA(1) proteins defined by mAb 125 and by hemagglutination in hibiting mAb 3E10, respectively. The N-terninal amino acid sequences of pMS A proteins (SENKLI... and SENETQ...) probably indicate the cleavage site of the M, synoviae strain ULB 925 hemagglutinin. (C) 1999 Federation of Europ ean Microbiological Societies. Published by Elsevier Science B.V. All right s reserved.