Version 1: Differences in the sequence analysis sequence analysis of pMGA 1.2 and pMGA 1.3 among isolated field strains of Mycoplasma gallisepticum that produce deformed eggs in laying hens.

Mycoplasmosis in poultry is a chronical disease that causes economical losses in farming, and it is difficult to eradicate in flocks. Mycoplasma gallisepticum (MG) is one agent of this disease, this bacterium has many important superficial proteins to get infection, working as adhesin, transporter and evasion of immune system. The adhesin lipoprotein designed as pMGA has this function, present variability antigenic and it is conformed for 9 regions being the sequences pMGA1.2 and pMGA1.3 which have a 97% identity of amino acid conformation, for this reason they could be stables segments. The aim of this study was to determine the differences and similar regions in field strains through M83178.1 sequence. From 18 field strains collected (16 form egg, 1 oviduct and 1 air sac) of laying hen flocks. The 18 strains typified as Myc. gallisepticum by PCR with mgc2 gene. There were performed 6 internal primers to cover all sequences, while MGS6 and MSWUV1853 strains were used as positive and negative controls respectively. The results showed more frequently amplification close to the C-terminal region, but interesting no field strain presented the same amplification region as MGS6. The bioinformatic analysis was made for internal segments 4 and 6 only, analysis shows cluster affinity at sequence 6, when the sequences were translated to amino acids through MEGA program, they were compatible with conserved sequences in Myco_haema proteins domains in the genus Mycoplasma that belong to Q7NAP3_MYCGA VlhA.3.04. Differences in the sequence analysis of the field strain were demonstrated, but at the same time was identified a homologue region protein domain what can indicate a genetic transference as consequence of bacteria evolution. The outcomes showed the dynamic variability in pMGA protein, whose difference could represent an important factor for the development for vaccines to provide protection against Myc. gallisepticum infection in chickens.