Sequence analysis of the S1 glycoprotein gene of infectious bronchitis viruses: identification of a novel phylogenetic group in Korea.
Twelve Korean infectious bronchitis viruses (IBVs) were isolated in the field from chickens suspected of being carriers of infectious bronchitis between 2001 and 2003. The S1 glycoprotein genes of these IBV isolates were amplified by reverse transcriptase-polymerase chain reaction (RTPCR) and analyzed by restriction fragment length polymorphism (RFLP) analysis. These Korean IBV isolates were classified into three groups according to their RFLP patterns obtained using the restriction enzyme HaeIII. Half of the twelve isolates were similar to the KM91 RFLP pattern, which is a common pattern in Korea. Three more isolates were related to the Arkansas strain pattern, but with some unique variations. The other three viruses showed variant RFLP patterns. For a comparison with the published sequences for non-Korean IBV strains, amplified PCR products from the twelve isolates were cloned and sequenced. The Korean IBV field isolates had 71.2-99.7% nucleotide sequence homology with each other and 45.9-80.7% nucleotide sequence homology with non-Korean IBV strains. With respect to the deduced amino acid sequence, the Korean IBV isolates had 71.5-99.3% similarity with each other and 44.9-80.3% similarity with non-Korean IBV strains. Phylogenetic tree analysis revealed that some of the IBV isolates appear to belong to a new group, different from the non-Korean IBV strains or from previously isolated Korean IBV strains. Specifically, the new Korean IBV isolates K10217-03, K3-3 and K1255-03 represented a separate group. These findings suggest that the Korean IBVs appear to be continuously evolving.
Jang
Ji-Hyun
JH
School of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon 200-701, Korea.
Sung
Haan-Woo
HW
Song
Chang-Seon
CS
Kwon
Hyuk-Moo
HM
D000595:Amino Acid Sequence; D000818:Animals; D018352:Coronavirus Infections / Q000662:veterinary* / Q000821:virology; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics*; D001351:Infectious bronchitis virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D011200:Poultry; D011201:Poultry Diseases / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D016415:Sequence Alignment / Q000662:veterinary; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics
D006023:Glycoproteins; D014764:Viral Proteins