Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Feline aminopeptidase N (fAPN) is a major cell surface receptor for feline infectious peritonitis virus (FIPV), transmissible gastroenteritis virus (TGEV), human coronavirus 229E (HCV 229E) and canine coronavirus (CCV). By using chimeric molecules assembled from porcine, human and feline APN we have analysed the determinants involved in the coronavirus receptor function of fAPN. Our results show that amino acids 670-840 of fAPN are critically involved in its FIPV and TGEV receptor function whereas amino acids 135-297 are essential for the HCV 229E receptor function. We also demonstrate that a chimeric molecule assembled from human and porcine APN is able to act as a receptor for FIPV. This is surprising as neither human nor porcine APN by themselves mediate FIPV infection. These results suggest that different determinants in the APN protein are involved in mediating the coronavirus receptor function.
J Gen Virol 1998 Jun
PMID:Characterization of determinants involved in the feline infectious peritonitis virus receptor function of feline aminopeptidase N. 963 79

G2 rotavirus was prevalent in a 1993 epidemic of acute gastroenteritis in Taiwan. In this study, the genetic relationship among G2 rotavirus strains was analysed. The VP7 genes were amplified and sequenced. Except for one strain isolated in 1981, the nucleotide sequences of the VP7 genes of most of the G2 rotaviruses were very similar (identity > 97%) and were closely related to that of a Japanese G2 reference strain, S2. The genetic relatedness of G2 rotaviruses was analysed further by RNA-RNA hybridization. The genomes of the major G2 strains of 1993 did not hybridize well with those of the G2 strains of previous seasons in RNA segments 1, 6 and 7. Partial nucleotide sequences of the VP1 gene were analysed and appeared to be similar among the major G2 strains from the same epidemic (identity > 98%), whereas the identity of the VP1 genes of the major G2 strains of the 1993 epidemic to those of previous seasons was only about 84%. Since the numbers of mutations accumulated in the VP1 and VP7 genes over a period of 10 years were comparable, the significant change in the VP1 genes of the major strains of the 1993 epidemic suggests that these G2 rotaviruses had evolved by genetic reassortment.
J Gen Virol 1999 Jun
PMID:Sequence analysis of VP1 and VP7 genes suggests occurrence of a reassortant of G2 rotavirus responsible for an epidemic of gastroenteritis. 1037 58

Cell-culture-adapted (ca) porcine epidemic diarrhoea virus (PEDV) contains three internal open reading frames (I ORF) within the nucleocapsid protein gene and lacks the downstream counterpart of porcine transmissible gastroenteritis virus ORF7 or feline infectious peritonitis virus ORF6a. To confirm whether such features also exist in wild-type (wt) PEDV, the 3' 1800 nucleotides of its genome were sequenced and were found to be identical to those of ca virus. The coding potential of I-1 ORF was ascertained by transient expression in Vero cells followed by immunofluorescence using antipeptide sera. The I-1 protein was synthesized as a 12 kDa non-phosphorylated PEDV-specific protein that was not present in detectable amounts in virions. However, a low copy number of I-1 in the virion would suggest it is a structural component. Nevertheless, identical nucleotide sequences and gene expression strategies of attenuated ca virus and its virulent parent, wt PEDV, demonstrate that the 3' 1800 nucleotides or the genes and gene products encoded therein may not contribute to virus attenuation.
J Gen Virol 1999 Aug
PMID:A novel internal open reading frame product expressed from a polycistronic mRNA of porcine epidemic diarrhoea virus may not contribute to virus attenuation. 1046 91

Transmissible gastroenteritis coronavirus (TGEV) agglutinates erythrocytes of several species by virtue of sialic acid binding activity of the surface protein S. We have isolated and characterized five haemagglutination-defective (HAD) mutants. In contrast to the parental virus, the mutants were unable to bind to porcine submandibulary mucin, a substrate rich in sialic acid. Each of the mutants was found to contain a single point mutation in the S protein (Cys155Phe, Met195Val, Arg196Ser, Asp208Asn or Leu209Pro), indicating that these amino acids are affecting the sialic acid binding site. In four of the HAD mutants a nearby antigenic site is affected in addition to the sialic acid binding site, as indicated by reactivity with monoclonal antibodies. The parental virus was found to have an increased resistance to the detergent octylglucoside compared to the HAD mutants. This effect depended on cellular sialoglycoconjugates bound to the virion. If the binding of sialylated macromolecules was prevented by neuraminidase treatment, the parental virus was as sensitive to octylglucoside as were the HAD mutants. We discuss the possibility that the sialic acid binding activity helps TGEV to resist detergent-like substances encountered during the gastrointestinal passage and thus facilitates the infection of the intestinal epithelium. An alternative function of the sialic acid binding activity - accessory binding to intestinal tissues - is also discussed.
J Gen Virol 2000 Feb
PMID:Characterization of the sialic acid binding activity of transmissible gastroenteritis coronavirus by analysis of haemagglutination-deficient mutants. 1064 48

Human astroviruses are an important cause of gastroenteritis. As part of a molecular epidemiological study carried out in Mexico a human astrovirus isolate, Yuc-8, was adapted to grow in CaCo-2 cells, and its entire genome was sequenced. A 15 amino acid deletion in ORF1a, which has been associated with adaptation of astroviruses to grow in cells other than CaCo-2, was present in Yuc-8. Comparative sequence analysis of the Yuc-8 ORF2 with reported human astrovirus sequences revealed that this isolate belongs to genotype (serotype) 8. Two distinct domains in ORF2 were observed: an amino-terminal domain (residues 1 to 415), with identities higher than 81% among the strains analysed, and a carboxy-terminal domain (residues 416 to 782) with identities between 36 and 60%. Two non-superimposable phylogenetic trees were generated by separate analysis of these two domains, suggesting that a differential selective pressure is exerted along the structural polyprotein.
J Gen Virol 2000 Dec
PMID:Molecular analysis of a serotype 8 human astrovirus genome. 1108 20

Five recombinant porcine adenoviruses of serotype 5 (PAdV-5) carrying the full-length or the 5' 2.2 kb half of the transmissible gastroenteritis virus (TGEV) spike (S) gene were generated by homologous recombination in E. coli strain BJ5183 cells and subsequent transfection of swine testicle cells. The foreign genes were inserted into the E3 region of PAdV-5. One recombinant virus had no deletion in the E3 region, whereas a 1.2 kb fragment was removed from the E3 region in the remainder of the recombinant viruses. One stable construct with a 4.4 kb insertion had a genome size of 109.6% of the wild-type genome, the largest reported for any recombinant adenovirus. Only those viruses that carried the S gene in the left to right orientation expressed the S gene. Three recombinant viruses were tested by oral immunization of pigs and both antibody response and virus shedding were monitored. None of the pigs showed clinical signs and the virus was recovered from rectal swabs until 6-7 days post-infection. Viruses expressing the S gene induced TGEV- and PAdV-5-specific virus-neutralizing antibodies. Moreover, TGEV-specific secretory IgA was detected in the small intestine and in the lungs of the immunized animals.
J Gen Virol 2001 Jan
PMID:Construction and characterization of recombinant porcine adenovirus serotype 5 expressing the transmissible gastroenteritis virus spike gene. 1112 71

A helper-dependent expression system based on transmissible gastroenteritis coronavirus (TGEV) has been developed using a minigenome of 3.9 kb (M39). Expression of the reporter gene beta-glucuronidase (GUS) (2-8 microg per 10(6) cells) and the porcine respiratory and reproductive syndrome virus (PRRSV) ORF5 (1-2 microg per 10(6) cells) has been shown using a TGEV-derived minigenome. GUS expression levels increased about eightfold with the m.o.i. and were maintained for more than eight passages in cell culture. Nevertheless, instability of the GUS and ORF5 subgenomic mRNAs was observed from passages five and four, respectively. About a quarter of the cells in culture expressing the helper virus also produced the reporter gene as determined by studying GUS mRNA production by in situ hybridization or immunodetection to visualize the protein synthesized. Expression of GUS was detected in the lungs, but not in the gut, of swine immunized with the virus vector. Around a quarter of lung cells showing replication of the helper virus were also positive for the reporter gene. Interestingly, strong humoral immune responses to both GUS and PRRSV ORF5 were induced in swine with this virus vector. The large cloning capacity and the tissue specificity of the TGEV-derived minigenomes suggest that these virus vectors are very promising for vaccine development.
J Gen Virol 2002 Mar
PMID:In vitro and in vivo expression of foreign genes by transmissible gastroenteritis coronavirus-derived minigenomes. 1184 52

The key enzyme in coronavirus replicase polyprotein processing is the coronavirus main protease, 3CL(pro). The substrate specificities of five coronavirus main proteases, including the prototypic enzymes from the coronavirus groups I, II and III, were characterized. Recombinant main proteases of human coronavirus (HCoV), transmissible gastroenteritis virus (TGEV), feline infectious peritonitis virus, avian infectious bronchitis virus and mouse hepatitis virus (MHV) were tested in peptide-based trans-cleavage assays. The determination of relative rate constants for a set of corresponding HCoV, TGEV and MHV 3CL(pro) cleavage sites revealed a conserved ranking of these sites. Furthermore, a synthetic peptide representing the N-terminal HCoV 3CL(pro) cleavage site was shown to be effectively hydrolysed by noncognate main proteases. The data show that the differential cleavage kinetics of sites within pp1a/pp1ab are a conserved feature of coronavirus main proteases and lead us to predict similar processing kinetics for the replicase polyproteins of all coronaviruses.
J Gen Virol 2002 Mar
PMID:Conservation of substrate specificities among coronavirus main proteases. 1184 54

Noroviruses (NoVs) are a leading cause of gastroenteritis worldwide and are recognized as the foremost cause of foodborne illness. Despite numerous efforts, routine cell cultures have failed to yield replicating NoV. This paper describes methods used to try to grow NoV in vitro in two laboratories. Cells (A549, AGS, Caco-2, CCD-18, CRFK, CR-PEC, Detroit 551, Detroit 562, FRhK-4, HCT-8, HeLa, HEC, HEp-2, Ht-29, HuTu-80, I-407, IEC-6, IEC-18, Kato-3, L20B, MA104, MDBK, MDCK, RD, TMK, Vero and 293) were cultured on solid or permeable surfaces. Differentiation was induced using cell culture supplements such as insulin, DMSO and butyric acid. In some cases, the cells and the NoV-containing stool samples were treated with bioactive digestive additives. Variables evaluated in cultivation experiments included the method of preparation of the virus inoculum, the genotype of the virus, conditions for maintenance of cell monolayers, additives in the maintenance medium and the method of inoculation of the cells. Serial blind passage studies were performed routinely. In addition to evaluation for CPE, evidence of virus replication was sought using immunofluorescent assays to detect newly produced viral capsid antigen and RT-PCR assays to detect the viral genome. Although some infected cultures remained NoV positive by RT-PCR for up to five passages and an occasional cell in a monolayer showed evidence of specific immunofluorescence, no reproducible NoV-induced CPE was observed and all RT-PCR results that were positive initially were negative following continued passaging. Thus, attempts to develop a method for the cultivation of NoV were unsuccessful.
J Gen Virol 2004 Jan
PMID:Laboratory efforts to cultivate noroviruses. 1471 22

A cytopathic agent (A308/99) was isolated using Vero cells from a stool specimen of a 1-year-old patient with transient paralysis. The agent was approximately 28 nm in diameter with a distinct ultrastructure resembling the virus particle of an enterovirus. It could not be neutralized by antisera against human picornaviruses such as human enterovirus, Aichi virus or human parechovirus. The virion contained three capsid proteins with molecular masses of 38, 30.3 and 30 kDa. Determination of the complete nucleotide sequence of A308/99 revealed that the nucleotide and deduced amino acid sequences were closely related to those of human parechoviruses. When 11 regions encoding the structural and non-structural proteins were compared, A308/99 had between 75 and 97 % and 73 and 97 % nucleotide identity with human parechovirus type 1 (HPeV-1) and type 2 (HPeV-2), respectively. The most distinctive divergence was seen in VP1, which had 74.5 % and 73.1 % nucleotide identity with HPeV-1 and HPeV-2, respectively. Viruses related to A308/99 were also isolated from three patients with gastroenteritis, exanthema or respiratory illnesses. A308/99 and these other three isolates had no arginine-glycine-aspartic acid (RGD) motif, which is located near the C terminus of VP1 in HPeV-1 and HPeV-2. A seroepidemiological study revealed that the prevalence of A308/99 antibodies was low (15 %) among infants but became higher with age, reaching more than 80 % by 30 years of age. These observations indicate that A308/99 is genetically close to, but serologically and genetically distinct from, HPeV-1 and HPeV-2 and accordingly can be classified as third serotype of human parechovirus.
J Gen Virol 2004 Feb
PMID:Isolation and identification of a novel human parechovirus. 1476 96


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