Cloning and sequencing of 3ABC gene of foot and mouth disease virus type O from a Thai pig isolate from Ratchaburi province in 2005

Abstract

Foot and mouth disease (FMD) is an important epidemic disease of swine in Thailand. It causes negative effect on swine production and also creates export trade restriction. Consequently, the economic loss is enormous in swine industries. The major type of Foot and mouth disease virus (FMDV) found in Thailand and has been recently isolated from an outbreak in 2005 is FMDV type O. To control this disease is to distinguish the naturally infected swine from the vaccinated ones. In this study, viral RNA was extracted from vesicular fluid and erosion tissue found in coronary band of hoof in FMD infected pigs from Ratchaburi province in 2005. The first strand of FMDV-cDNA was synthesized by reverse transcription reaction. FMD Type O was confirmed by PCR technique using the O-1C124 primer set. Then, the full length of 3ABC gene was amplified by using PCR technique. The PCR products of 3ABC gene were cloned into pET160/GW/TOPO® vector. In addition, the nucleotide sequences were analyzed and compared with previously reported 3ABC nucleotide’s databases. The results showed that five clones of 3ABC expression vectors were successfully collected (1,303 bp). As a result, phylogenetic tree analysis of 3ABC nucleotides revealed that this gene of FMDV type O isolated from pig in Ratchaburi province in 2005 had 100 % homology to those of FMDV type O strain Tibet /CHA/99 (Genbank accession number is AJ539138).