INTRATYPIC GENOME VARIABILITY OF THE COXSACKIEVIRUS B1 2A PROTEASE REGION

To analyse the intratypic genome variability of coxsackievirus B1, 17 coxsackievirus B1 isolates were collected over a period of 10 years. N ucleotide sequences of the 2A coding region of the various coxsackievi rus B1 isolates and known sequences of other enteroviruses were compar ed. The maximum diversity observed within the entire group of coxsacki evirus B1 isolates was 25%. Comparison of deduced amino acid sequences revealed a maximum diversity of 5%. Phylogenetic analysis demonstrate s a close genetic relationship between these clinical isolates and the other different coxsackievirus B serotypes. Further analysis of nucle otide and amino acid sequences of the 2A region of known enteroviruses demonstrated that the genus enterovirus can be subdivided into a coxs ackievirus B-like group, including the coxsackie B viruses, coxsackiev irus A9, echovirus 11 and swine vesicular disease virus, and a poliovi rus-like group including the polioviruses 1 to 3, and the coxsackievir uses A21 and A24. Enterovirus type 70 and bovine enterovirus represent distinct groups. The 2A coding region of coxsackievirus B1 strains ca nnot be distinguished from that of other members of the coxsackievirus B-like group. Although conservation of the overall amino acid sequenc e was almost limited to residues essential for proposed enzymatic acti vity, the predicted secondary structures were well conserved within th e genus enterovirus.