Abstract: Foot-and-mouth disease virus strain OA/58 RNAs were used as templates for RT-PCR. The amplified cDNA products were cloned into pGEM-T Easy vectors and transformed into JM109. The recombinant plasmids were identified by electrophoresis, PCR, and EcoR I cleavage. The nucleotide and amino acid sequences were compared with the L genes of the other 4 reference strains. The results show that between 2 initiation codons, there is a special function sequence which enables small subunit of ribosome to recognize and utilize the second AUG to translate L protease that is called for Lb; the regions of 35-39th, 43-54th, 65-67th, 75-80th, 90-111th, 113-142th, 144-146th, 148-157th, 159-172th and 176-187th in L protease most probably are conservative. By homology modeling the FMDV strain OA/58 L protease, the 3D mold of this protease was obtained. Resolution of the 3D structure of L protease showed a compact globular form with a flexible C terminal extension from 187th to 201th. Depending on the region of hydrophilicity residues forming hydrophilicity power, L proteases can form dimmers. Lys144, His148 and Asp163 may be active amino acids which form the active site of L protease. By Ramachandran Plot showing, 3D mold of a FMDV strain OA/58 L protease is rather reasonable, this research should be used as an instruction in order to direct the work on FMDV L protease.

Key words: FMDV, L protease, Active site

CLC Number: 

• S852.66