RESUMO
Obtaining suitable seed viruses for influenza vaccines poses a challenge for public health authorities and manufacturers. We used reverse genetics to generate vaccine seed-compatible viruses from the 2009 pandemic swine-origin influenza virus. Comparison of viruses recovered with variations in residues 186 and 194 (based on the H3 numbering system) of the viral hemagglutinin showed that these viruses differed with respect to their ability to grow in eggs and cultured cells. Thus, we have demonstrated that molecular cloning of members of a quasispecies can help in selection of seed viruses for vaccine manufacture.
Assuntos
Surtos de Doenças , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/virologia , Mutação Puntual , Replicação Viral , Sequência de Aminoácidos , Animais , Linhagem Celular , Embrião de Galinha , Cães , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Vírus da Influenza A Subtipo H1N1/química , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/epidemiologia , Dados de Sequência Molecular , Alinhamento de SequênciaRESUMO
A new isofuranonaphthoquinone, 7,8-dihydroxy-1-methylnaphtho[2,3-c]furan-4,9-dione, was isolated from cultures of an Actinoplanes isolate obtained using an in situ diffusion technology that facilitates the isolation of soil microorganisms. This compound was demonstrated to have the ability to complex Fe(III). The structure was determined on the basis of spectroscopic data.
Assuntos
Actinomycetales/química , Furanos/isolamento & purificação , Naftoquinonas/isolamento & purificação , Furanos/química , Ferro/química , Ferro/metabolismo , Estrutura Molecular , Naftoquinonas/química , Ressonância Magnética Nuclear Biomolecular , Microbiologia do SoloRESUMO
Two novel antibiotics, neocitreamicins I and II, were isolated from a fermentation broth of a Nocardia strain. This producing strain was obtained using an in situ diffusion chamber that facilitates the cultivation of soil microorganisms. The structures of neocitreamicins I and II were elucidated using UV, MS, and NMR data, and found to be related to the polycyclic xanthone antibiotics of the citreamicin class. The neocitreamicins showed in vitro activity against Gram-positive bacteria including strains of methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis.