RESUMO
The analysis of recently published data on hepatitis A virus (HAV) genome clinical features, molecular diagnostic value and cell culture propagation are reviewed. The growing need in the study of the genetic diversity of HAV isolates and the search of its possible new antigenic variants are underlined. The results of the cultivation of different HAV strains are analyzed for possible application in vaccine and diagnostic kit production.
Assuntos
Variação Genética , Genoma Viral , Vírus da Hepatite A , Hepatite A , Kit de Reagentes para Diagnóstico , Animais , Hepatite A/diagnóstico , Hepatite A/genética , Hepatite A/metabolismo , Antígenos da Hepatite A/genética , Antígenos da Hepatite A/metabolismo , Vírus da Hepatite A/genética , Vírus da Hepatite A/crescimento & desenvolvimento , Vírus da Hepatite A/metabolismo , HumanosRESUMO
Complete nucleotide sequence of genomic RNA of hepatitis A virus (HAV) rapidly replicating strain MB-7 was determined. Comparison of nucleotide and deduced amino-acid sequences demonstrated the highest level of identity of MB-7 with strain HAS-15 (above 99%) and high homology with other HAV strains (HM 175/7, CR326, and GBM/HFS) used in production of anti-hepatitis A vaccines. MB-7 was classified as subgenotype IA. Phylogenetic analysis showed that MB-7 is most closely related to the strain HAS-15 and the HAV variants circulating in Russia. Comparative analysis of genomic differences between MB-7 and HAS-15 with other HAV strains revealed among changes characteristic of MB-7 those typical of the described earlier rapidly replicating HAV strains (nt. 149-162 in 5'-untranslated region and changes in the VP3 and 2C genes). These results suggest the functional importance of changes in above-mentioned regions of HAV genome for the increased replication level of MB-7 in vitro.
Assuntos
Vírus da Hepatite A Humana/genética , Hepatite A/virologia , RNA Viral/genética , Replicação Viral , Sequência de Bases , Vírus da Hepatite A Humana/classificação , Humanos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de RNA , Homologia de Sequência do Ácido Nucleico , Proteínas Virais/genéticaRESUMO
The nucleotide sequences of a region of VP1/2A genes of a large group of hepatitis A virus (HAV) isolates circulating in Siberia (the Altai Territory, the Irkutsk and Novosibirsk Regions) were determined. Comparison of these sequences with those of prototype HAV of genotypes IA, IB, and IIA revealed their high similarity to prototype genotype IA strains. The above domains were shown to contain the types of viruses, which were close to both the European subtypes of HAV genotypes IA (78.3%) and the Far Eastern subtypes of this genotype (21.7%). The similar comparison of the derived amino acid sequences suggests that VP1 and 2A contains the amino acid substitutions that are typical of this geographical region.
Assuntos
Vírus da Hepatite A/genética , Substituição de Aminoácidos , Cisteína Endopeptidases/genética , Variação Genética , Hepatite A/virologia , Vírus da Hepatite A/isolamento & purificação , Humanos , Sibéria , Especificidade da Espécie , Proteínas Virais/genética , Proteínas Estruturais Virais/genéticaRESUMO
On the basis of coding regions on the fragments of genes P1 and P2 of hepatitis A virus (HAV) recombinant proteins of this virus have been synthesized in the prokaryotic expressing system of E. coli, isolated and studied with the use of sera obtained from hepatitis A patients. The capacity of HAV recombinant proteins for binding with the sera of patients with hepatitis A in the acute stage has been shown with the use of immunoblotting and the indirect solid-phase enzyme immunoassay. The results obtained in this investigation are discussed in the light of the possible use of recombinant proteins for the detection of HAV markers.
Assuntos
Escherichia coli/metabolismo , Genoma Viral , Hepatovirus/metabolismo , Poliproteínas/metabolismo , Proteínas Virais/metabolismo , Proteínas Sanguíneas/metabolismo , Western Blotting , Escherichia coli/genética , Hepatite A/sangue , Hepatovirus/genética , Humanos , Técnicas Imunoenzimáticas , Poliproteínas/genética , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Virais/genéticaRESUMO
The bisulphite-catalysed transamination of cytosine residues by means of ethylenediamine generally used for the natural nucleic acids modification has been extended on relatively short synthetic oligonucleotides. One of the aminoalkyloligonucleotides thus obtained has been used for preparing a biotinylated hybridisation probe.
Assuntos
Aminas/química , Citosina/química , Oligodesoxirribonucleotídeos/química , Alquilação , Sequência de Bases , Biotina/metabolismo , Eletroforese em Gel de Poliacrilamida , Dados de Sequência MolecularRESUMO
Efficiencies of biotinylated DNAs as hybridisation probes in a model system of non-radioactive detection were compared. Probes were obtained by interaction of single-stranded DNA and each of four different hydrazides of biotin derivatives. The most sensitivity in detection of complementary target was obtained using (biocytin hydrazide)-treated DNA. Relations between hydrazide structures and sensitivity of biotinylated probes are discussed.