RESUMO
A comparative study of chromatography and centrifugation as applied to purification of 2 influenza virus strains with different antigenic structure (H0N1 and H2N2) and of some biological properties of the resulting preparations was carried out. Certain strain-specific differences manifested in their chromatographic behaviour and in the degree of purification of virions from the allantoic fluid proteins were found. Some quantitative differences observed in the capacity of the resulting virus preparations to infect chick embryos and primary and continuous cells are insignificant and cannot be used for judgement of advantages of one or the other of the methods used for influenza virus purification.
Assuntos
Vírus da Influenza A/isolamento & purificação , Animais , Centrifugação Isopícnica/métodos , Embrião de Galinha , Cromatografia DEAE-Celulose/métodos , Cromatografia em Gel , Especificidade da Espécie , Ultracentrifugação/métodosRESUMO
A thiol proteinase was isolated from buckwheat seeds and purified 300-fold, using ammonium sulfate, acetone fractionation ion-exchange chromatography on Sephadex CM-50 and electrofocussing. The proteinase preparation obtained was found homogenous after polyacrylamide gel electrophoresis at pH 4.5. The molecular weight of the enzyme (75.000) was determined by gel-filtration through Sephadex G-100. The activation of proteinase by cysteine, 2-mercaptoethanol and dithiothreitol, its inhibition by p-chloromercurybenzoate and the absence of inhibition by diisopropyl fluorophosphate and EDTA suggest that the enzyme isolated is a thiol proteinase. The enzyme hydrolyzed many peptide bonds in the B-chain of insulin, showing high substrate specificity. The glutelin and globulin fractions of buckwheat seed proteins were hydrolyzed by the enzyme. It is assumed that the hydrolysis of reserve proteins of buckwheat seeds is the main function of the proteinase isolated.