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R S Kataria

Publications and source records attributed to R S Kataria.

At least 19 recordsLinked to original sources

Sequence analysis of VP7 gene of Indian bluetongue virus serotype-23 shows its close phylogenetic relationship to Australian and Chinese serotypes.

Bluetongue, an arthropod borne viral disease of wild and domestic ruminants, causes heavy economic losses throughout the world. In the present study, full-length VP7 gene of Indian bluetongue virus (BTV) serotype 23 was sequenced and compared with prototype strains of BTV reported from different countries. Nucleotide sequence analysis of VP7 gene revealed Indian BTV serotype 23 to have 1154 nucleotides with the deletion of two nucleotides at 3' non-coding region and a unique amino acid change 211S-N. The Indian virus also demonstrated a maximum similarity of 94.2% with Australian serotype 1 and a minimum similarity of 67.4% with Australian serotype 15. However, at deduced amino acid level, it had maximum similarity of 99.7% and a minimum of 82.5% with Chinese serotypes 1, 2 and 4 and Australian serotype 15, respectively. Deduced amino acid sequence analysis of putative receptor binding domain (121-249) revealed all the nine hydrophilic domains to be conserved across the serotypes. Functional motifs present in VP7 protein were also conserved in almost all the BTV serotypes including Indian serotype 23. Phylogenetic analysis based on VP7 gene sequence revealed Indian BTV serotype 23 segregating into a monophyletic group along with Australian serotype 1 and Chinese serotypes 1, 2 and 4, indicating its close evolutionary relationship with these Australian and Chinese serotypes.

Amino Acid Sequence↗

Differential detection of Newcastle disease virus strains by degenerate primers based RT-PCR.

Degenerate primers based RT-PCR (previously described by [Avian Dis 26 (1997) 837]) has been used for the detection and differentiation of Newcastle disease (ND) viruses. Two sets of primers (A+B and A+C), with common forward primer and distinct reverse degenerate primers, designed from fusion protein gene encoding for cleavage site, could differentiate virulent and avirulent Newcastle disease viruses (NDV). Both sets of primers amplified "F" gene sequence of virulent (velogenic and mesogenic) viruses, whereas in avirulent strains, amplification was only with primer set A+C. Total 10 NDV isolates and two clinical samples including both known and unknown pathotypes, were checked. Based on amplification results 5 viruses were found to be virulent type and 6 as avirulent with one of the two clinical samples, earlier positive by RT-PCR using non-degenerate "F" gene specific primers was found negative in this study. The technique has been found to be a simple and quick for the detection and differentiation of virulent and avirulent NDV, which is important for control of the disease in the events of the outbreaks.

Animals↗

Differentiation of infectious bursal disease viruses by restriction enzyme analysis of RT-PCR amplified VP1 gene sequence.

In order to differentiate infectious bursal disease virus (IBDV) isolates/strains, a quick method of RT-PCR followed by restriction enzyme analysis of VP1 gene sequence is being reported for the first time. A 480 bp fragment, comprising one of the RNA dependent RNA polymerase motifs of VP1 gene sequence of an Indian classical virus, an attenuated vaccine strain, Georgia and two Indian field isolates, genetically similar to reported very virulent strains of IBDV, was amplified by RT-PCR. Restriction enzyme digestion of PCR products with Taq1 enzyme generated distinct profile for field isolates, different from the classical and attenuated viruses, whereas restriction profile with BstNI restriction enzyme was similar in all the viruses, irrespective of the pathotype. Therefore, the present results suggest that Taq1 digestion can be taken up for the differentiation of field isolates from the classical and vaccine strains. The sequence analysis of VPI gene of reported very virulent IBD viruses from Europe and Japan, using 'MapDraw' programme of Lasergene software, revealed similar restriction enzyme profile as in Indian field isolates.

Animals↗

Sequence analysis of segment a of a field virus isolate from an outbreak of Infectious bursal disease in India.

Sequence analysis of genome segment A of an Indian Infectious bursal disease virus (IBDV) field isolate (KT1/99) revealed total 95 nucleotide substitutions, resulting in 17 amino acid changes. Of these, five amino acid changes, namely F60S, T137I, I374V, V519I and E682D were unique to the KT1/99 isolate. The amino acid change P222A and the proposed hot mutation spot 680Y, reported to be present in very virulent IBDV isolates were also found in KT1/99. This isolate had nucleotide divergence of 1.1% to 4.95% from the other reported serotype 1 IBDV isolates and 19.6% from serotype 2 strain OH in polyprotein gene sequence, while divergence at amino acid level was 0.6% to 2.9% and 11.4%, respectively. Based on both nucleotide and amino acid sequence analysis, KT1/99 was grouped phylogenetically with the reported Bangladesh isolate BD3/99 in one cluster along with other reported very virulent isolates in same lineage.

Amino Acid Sequence↗

Isolates of infectious bursal disease virus from India are of very virulent phenotype.

Four Indian field isolates, a classical virulent and an attenuated vaccine strains of Infectious bursal disease virus (IBDV) have been characterized by sequence analysis of part of the VP1 gene (from nucleotide 1538-1979) comprising one of viral RNA dependent RNA polymerase motifs. Sequence alignment of these viruses with reported viruses of other countries revealed Indian IBDV field isolates to be 100% similar to very virulent Japanese (OKYM), European (UK661) and Bangladesh (BD3/99) IBD viruses at amino acid level, whereas they had 0.2-0.9% divergence at nucleotide level. Out of the total 24 nucleotide changes found in the Indian field isolates, as well as reported very virulent viruses, only one resulted in amino acid change S-P at 562 position. The Indian field isolates displayed nucleotide divergence of 10.6-11.6% and amino acid divergence of 2.8-3.5% from the classical virulent and attenuated vaccine strains. The RNA dependent RNA polymerase motif from amino acid 528-541, present in the sequence analyzed, was conserved among all the viruses, irrespective of pathotype and serotype. In the phylogenetic tree, based on nucleotide sequence, Indian field viruses were grouped with reported very virulent viruses in one lineage whereas, classical virulent, attenuated vaccine and serotype 2 strains formed part of the second lineage. But in the phylogenetic tree based on amino acid sequence alignment, the serotype 2 strain OH grouped with Indian field isolates and reported very virulent viruses in one lineage and classical virulent and attenuated vaccine strains formed the second lineage.

Amino Acid Sequence↗

Characterisation of fowl adenoviruses from chickens affected with infectious hydropericardium during 1994-1998 in India.

In the present study characterisation has been done for six group I fowl adenoviruses (FAV) isolated from outbreaks of infectious hydropericardium (IHP) of chickens that occurred in different states/regions of India during the years 1994-98. These six viruses were identified as FAV serotype 4 by virus neutralisation and restriction endonuclease analyses. Antigenic analyses of the viruses revealed close relationship (R-values 0.93-0.96). Under the experimental conditions, we have been able to induce IHP using FAV serotype 4 isolate AD: 411 and were also able detect FAV antigens in myocardial tissues by immunofluorescence assay (a new observation), an indication that IHP causing FAV serotype 4 strain replicate in myocardial tissue. Restriction endonuclease analysis of the viral genomes (approximately 46 Kb), using Hind III, Sma I, Xba I, Bam HI, Pst I and Dra I produced identical genetic profiles. Pst I and Bam HI profiles for these six vitus isolates were identical to those published earlier for an IHP causing Pakistani FAV serotype 4 isolate KR31. The identical genetic profiles of viruses, chronology of the outbreaks of IHP in Pakistan during 1989 onward and later in Jammu and Kashmir, India (1994), suggest that FAV serotype 4 isolates involved in outbreaks of IHP in India had probably spread from Pakistan. In order to prevent further spread and economic losses due to IHP in India, based on the antigenic relatedness data in this paper, any one of the six studied FAV serotype 4 isolates can be used as a candidate for mass production of CEH culture based killed vaccine.

Adenoviridae Infections↗

Characterization of fowl adenovirus serotype-4 associated with hydropericardium syndrome in chicken.

The polypeptides of three fowl adenovirus-4 (FAV-4) field isolates of hydropericardium syndrome from various geographical areas of the country and the standard FAV-1 (CELO virus) were subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis and analysed by protein immunoblotting with polyclonal antibodies to FAV-4 and FAV-1. Protein profile analysis of FAV-4 isolates revealed similarity of all the eight polypeptides with molecular weight ranging from 20 to 107 kDa but differed from CELO, particularly in their 24.2 kDa protein. Subsequent immunoblotting showed relatedness of at least five protein fractions of FAV-4 to CELO virus.

Adenoviridae Infections↗

One-step RT-PCR for the detection of infectious bursal disease virus in clinical samples.

A single-tube, non-interrupted, one-step RT-PCR has been standardized to amplify the hypervariable region of the VP2 gene sequence of infectious bursal disease virus (IBDV). The technique standardized on purified viral RNA was successfully applied to the detection of the virus directly in clinical samples. The amplified products were confirmed to be IBDV specific by their size in ethidium bromide-stained agarose gel, nested PCR and restriction enzyme digestion. Digestion of the amplicons with StyI restriction enzyme also differentiated classical virus from six very virulent field isolates. The sensitivity of the one-step RT-PCR was found to be 0.2 pg of viral RNA.

Animals↗

Identification of Trypanosoma evansi by DNA hybridisation using a non-radioactive probe generated by arbitrary primer PCR: short communication.

A highly reproducible, dominant, monomorphic fragment of 473 base pair (bp) amplified from the genome of Trypanosoma evansi by arbitrary primer-polymerase chain reaction (AP-PCR) was labelled with digoxigenin and investigated for its potential as DNA probe. Dot-blot hybridisation of total genomic DNA with the probe proved useful in detecting bubaline, cameline and equine strains of T. evansi down to 10 pg of parasite template DNA. No cross-hybridisation was seen with Babesia bigemina, Theileria annulata and the bubaline host DNA. This probe may facilitate laboratory identification of T. evansi in developing countries, without the inherent risk associated with radioisotopes.

Animals↗

Pathotyping of Newcastle disease viruses by RT-PCR and restriction enzyme analysis.

The technique of RT-PCR and restriction enzyme analysis was standardized to detect and differentiate Newcastle disease viruses. Digestion of RT-PCR-amplified, F gene sequences encoding for the cleavage activation sites of fusion protein with restriction enzymes AluI, BglI, HaeIII, HinfI, HhaI, RsaI, StyI and TaqI was carried out in order to characterize Newcastle disease viruses of varying pathogenicity. Restriction enzyme digestion of the amplicons by BglI and HhaI could group eight viruses, both field isolates and known vaccine strains, into lentogenic, mesogenic and velogenic pathotypes. By employing this technique directly on a clinical sample, Newcastle disease virus of the lentogenic pathotype could be detected.

Animals↗

Characterization of an Indian bluetongue virus isolate by RT-PCR and restriction enzyme analysis of the VP-7 gene sequence.

The reverse transcription-polymerase chain reaction (RT-PCR) was standardized to amplify the VP-7 gene sequences of an Indian isolate of bluetongue virus serotype 23. Using two different sets of primers, a sequence of 1156 bp comprising the complete coding sequence of the VP-7 gene and its 770 bp internal sequence were amplified. The sensitivity of RT-PCR, using these two sets of primers individually was 40 pg and 4 pg, with the external and internal primers, respectively, whereas the nested PCR was 100-fold more sensitive than the single PCR with the external primers. Further, by restriction enzyme digestion of the 1156 bp amplicon, using CfoI, PstI and TaqI enzymes, the Indian isolate was found to be genetically different from isolates from the United States and Australia. RT-PCR and restriction enzyme digestion were applied to detect virus directly in blood samples taken from sheep suspected of bluetongue virus infection.

Animals↗

Purification and differentiation of three avian adenoviruses by restriction endonuclease analysis.

A rapid method of ultracentrifugation pelleting of avian adenovirus (AAV) from small volume of chloroform treated infected cell culture fluid or allantoic fluid was adapted for isolation of adenoviral DNA. The viral DNA extracted from semipurified viruses was found to be intact on agarose gel and pure enough (A260/280 = 1.85-1.92) for restriction enzyme analysis. Restriction endonuclease analysis of Indian strain of AAV serotype 1, AAV serotype 4 (group I AAVs) and egg drop syndrome-76 (EDS-76) virus genomes (group III AAV) with Hind III enzyme differentiated these viruses. The AAV serotype 1 and serotype 4 strain exhibited identical Hind III profile to European viral strains belonging to same serotypes however, the EDS-76 virus gave similar but not identical profile. The calculated genomic lengths for AAV serotype 1 and EDS-76 virus were approximately found to be 33.9 and 44.4 Kb, respectively.

Animals↗

Differentiation of infectious bursal disease virus strains by restriction analysis of RT-PCR-amplified VP2 gene sequences.

The techniques of reverse transcription-polymerase chain reaction (RT-PCR) and restriction analysis were used to differentiate highly virulent Indian field isolates of infectious bursal disease virus (IBDV) from vaccine strains. Primers were designed to amplify the variable region of VP2 gene coding for major virus neutralizing epitopes. The 552 bp PCR products generated from four vaccine strains and five field isolates were digested with restriction enzymes DraI, HhaI, MvaI, StuI, StyI, and TaqI, which could differentiate field isolates from vaccine strains. Based on restriction enzyme profiles derived from published sequences, Indian field isolates seem to be closely related to highly virulent Japanese, European, and Chinese strains of the virus.

Animals↗

Detection of infectious bursal disease virus of poultry in clinical samples by RT-PCR.

The RT-PCR technique was adopted to amplify variable region of VP2 gene of infectious bursal disease virus using three different sets of primers. These primers could generate products of 643, 474 and 552 bp sizes. The authenticity of the amplicons was confirmed by their size in agarose gel, restriction enzyme digestion and by nested PCR. Out of total five clinical samples tested, IBD viral genomic RNA could be detected in four by RT-PCR. Restriction enzyme digestion of PCR products with StuI could differentiate clinical samples from an intermediate vaccine strain currently being used in India.

Animals↗

Detection of bluetongue virus genome segment 6 sequences by RT-PCR.

Reverse transcription-PCR (RT-PCR) technique was adopted to amplify a 101 basepair nucleotide sequence of bluetongue virus (BTV) genome segment 6. The specificity of the amplicon was determined by its approximate size in 3% agarose gel electrophoresis, digestion with restriction enzyme MspI, dot-blot hybridization and cycle sequencing. The technique was found to be suitable for detection of bluetongue virus in infected cell culture and clinical samples.

Base Sequence↗

Detection of bovine herpesvirus 1 (BHV-1) genomic sequences in bovine semen inoculated with BHV-1 by polymerase chain reaction.

Polymerase chain reaction (PCR) technique was applied to detect BHV-1 in bovine semen inoculated with BHV-1. The technique was found to be 10(6) times more sensitive than a non-isotopic dot-blot hybridization method in detecting viral genomic DNA. Of the three primer pairs used, the one chosen from glycoprotein gC appeared to be most sensitive as it could detect up to 0.01 TCID50 of BHV-1 in the semen. The technique could be useful in screening breeding bulls or samples of frozen semen prior to use in artificial insemination.

Animals↗