Sequence and Analyzing of P2 Tract from a Virulent Foot and Month Disease Virus Strain China/99

Using a virulent foot and mouth disease virus strain China/99 RNA as templet to reverse transcript,amplify its P 2 tract with a pair of primers.The amplified cDNA products were cloned into pGEM-T Easy Vectors and transformed into JM 109 ,the recombinant plasmids were identified by electrophoresis,EcoR1 cleavage,and PCR.The nucleotide sequence of the expected P 2tract was determined by Sangers DNA sequence method,and amino acid sequence was compared with the P 2tracts of the other three FMDV strains.It was shown that the differential ratios of P2 tract of China/99 with O 1K,A 12 and TW45 strains were 7.79%,6.62% and 13.79% respectively and deduced animo acid sequence were 1.23%,1.85% and 5.74%,respectively.The sequence alignment of these strains shows that the higher conversions in T-C,A-G and A-C,hot nucleotides,mostly affect the stable of amino acid residues.