RESUMO
Permafrost is widely distributed in the Northern Hemisphere, and its age reaches hundreds of thousands and millions of years. Permafrost contains alive microorganisms which are not frozen due to relatively high temperature of the environment (-2...-8 degrees C), but the microorganisms are immobilized and therefore aged probably similar to the age of permafrost. Longevity of the relict microbial cells is related obviously to their mechanism of protection against heat, radiation, free radicals and other damaging agents. A strain of Bacillus sp. was isolated from permafrost aged of about 3 million years, 16S rDNA sequence was identified and preliminary testing of bacterial culture on Drosophila melanogaster and mice was made. Immune stimulation and improvement of physical condition were observed, and that, together with the age of the microbial cells, presents the relict microorganisms as objects of gerontology.
Assuntos
Envelhecimento/imunologia , Envelhecimento/fisiologia , Bacillus/crescimento & desenvolvimento , Bacillus/fisiologia , Clima Frio , Geriatria/métodos , Animais , Bacillus/isolamento & purificação , DNA Bacteriano/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/imunologia , Drosophila melanogaster/microbiologia , Imunidade Celular/fisiologia , Imunidade Humoral/fisiologia , Camundongos , Camundongos Endogâmicos , RNA Ribossômico 16S/genética , Sibéria , Microbiologia do Solo , Baço/imunologia , Timo/imunologia , Fatores de TempoRESUMO
Mutation Y168H of the human phenylalanine hydroxylase (PAH) gene determining phenylketonuria was described only twice: in a patient from Catalonia (Spain) and by us in a patient from Western Siberia (Russia). The association of Y168H in these families with allelic variants of STR and VNTR repeats and a number of neutral point polymorphisms of the PHA gene (IVS3nt-22C > T, Q232Q, V245V, L385L) was studied in this work. The Y186H mutation in these families was found to be associated with different haplotypes. Strong linkage of the selected markers and the mutation region excludes recombination as a possible cause of association of Y168H with different haplotypes. It was concluded that Y168H occurred independently in different populations.
Assuntos
Ligação Genética , Mutação de Sentido Incorreto , Fenilalanina Hidroxilase/genética , Fenilcetonúrias/genética , Polimorfismo Genético , Haplótipos , Humanos , Sibéria , EspanhaRESUMO
A new approach to the identification of point mutations by allele-specific PCR was proposed. The mutation R408W of the human phenylalanine hydroxylase gene was used as a model. A high specificity of the approach was achieved by the use of primers partially complementary to the genomic DNA. Polyethylene glycol covalently attached to one of the allele-specific primers provides for the differential identification of the PCR products due to a change in electrophoretic mobility.
Assuntos
Mutação Puntual , Polimorfismo de Nucleotídeo Único , Alelos , Primers do DNA , Eletroforese em Gel de Ágar , Humanos , Fenilalanina Hidroxilase/genética , Fenilcetonúrias/genética , Reação em Cadeia da PolimeraseRESUMO
Mutations were studied in phenylalanine hydroxylase gene of phenylketonuria patients from Kemerovo oblast and Altaiskii krai (15 and 2 families, respectively). The following mutations were identified in exons of this gene: R408W, R261Q, R243Q, Y414C, Y386C, P281L, Y168H, R68S (lead to amino acid substitutions), R243X (leads to stop codon formation), and three splice site mutations (IVS12nt 1g-->a, IVS2nt-13t-->g, IVS7nt 1g-->a).