title: Field isolates of transmissible gastroenteritis virus differ at the molecular level from the Miller and Purdue virulent and attenuated strains and from porcine respiratory coronaviruses.
abstract: The diversity in selected regions of the transmissible gastroenteritis virus (TGEV) and porcine respiratory coronavirus (PRCV) genomes was analyzed among known TGEV and PRCV strains and field isolates. The N-terminal half of the spike (S) glycoprotein gene and open reading frames (ORF) 3, 3-1 and 4 were amplified by reverse transcriptase reaction and polymerase chain reaction (RT/PCR), and analyzed using restriction fragment length polymorphism (RFLP) patterns of the amplified DNA. Reference TGEV strains (Miller and Purdue) and a PRCV strain (ISU-1), and TGEV and PRCV field isolates were analyzed. Based on the size of the ORF 3, 3-1 and 4 RT/PCR products, TGEV and PRCV strains could be quickly and easily differentiated into three groups designated TGEV Miller, Purdue types and PRCV. By RFLP analysis of the N-terminal region of the S glycoprotein gene and ORFs 3, 3-1 and 4, TGEV and PRCV strains were differentiated into five groups using the restriction enzyme Sau3AI. Sequence analysis of a PCR product in the ORFs 3, 3-1 and 4 from virulent and attenuated Miller strains demonstrated additional differences in that region which have been correlated with a change in virulence of TGEV isolates.
authors.affiliation: Department of Veterinary Preventive Medicine, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster 44691, USA.
authors.forename: H M
authors.initials: HM
authors.lastname: Kwon
authors.forename: L J
authors.initials: LJ
authors.lastname: Saif
authors.forename: D J
authors.initials: DJ
authors.lastname: Jackwood
mesh_terms: D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D018352:Coronavirus Infections / Q000662:veterinary* / Q000821:virology; D005761:Gastroenteritis, Transmissible, of Swine / Q000821:virology; D014644:Genetic Variation; D016679:Genome, Viral; D008297:Male; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D019318:Porcine Reproductive and Respiratory Syndrome / Q000821:virology; D019316:Porcine respiratory and reproductive syndrome virus / Q000235:genetics* / Q000302:isolation & purification; D017384:Sequence Deletion; D012689:Sequence Homology, Nucleic Acid; D013552:Swine; D013737:Testis / Q000166:cytology / Q000821:virology; D005760:Transmissible gastroenteritis virus / Q000235:genetics* / Q000302:isolation & purification