Anaplasma marginale: analysis of variable fragment sequences in msp1α and msp4 genes in four new Mexican strains.

Bovine anaplasmosis, due to Anaplasma marginale, is responsible for substantial economic losses in livestock production of developing countries. Vaccine development is hampered by wide genetic and antigenic diversity in strains of distant geographical areas. The objective of the present study was to compare sequences of four non typified Mexican A. marginale strains in respect of msp1α and msp4 genes. Sequences of MSP-1a and MSP4 and major surface complex proteins were used, already used for phylogenetic studies. Through specific initiators, for variable areas of both the msp1 á and msp4 genes, DNA of the Pte. de Ixtla, Mor.; Aguascalientes, Ags; Pichucalco and Sta. Martha, Chis. strains was amplified. Analyses of nucleotide sequences and amino acids for msp1α showed a strong similitude between Pichucalco and Sta. Martha, both from Chiapas, same as against the isolates Mexico, Morelos and Veracruz. Isolates Pte. de Ixtla and Aguascalientes were different between them and previously identified Mexican strains and from other countries, while for msp4 no variation was reported for Mexican strains previously reported, which contain 849 pb and coincide with different isolates the world over. Studies comprising either regions or the whole country on the conservation rank of these proteins could open possibilities for vaccines based on these antigens and its efficacy could be predicted. [ABSTRACT FROM AUTHOR]