Avtor/Urednik		Pogačar, Martina
Naslov		Ločitev in delna karakterizacija 17beta-hidroksisteroidne dehidrogenaze in beta-hidroksibutiril CoA dehidrogenaze iz glive Pleurotus ostreatus
Tip		monografija
Kraj izdaje		Ljubljana
Založnik		Medicinska fakulteta
Leto izdaje		1999
Obseg		str. 70
Jezik		slo
Abstrakt		HSD's are NAD(P)+/NAD(P)H dependent oxidoreductases, catalysing stereospecific and reversibile interconversions of keto and hydroxy steroids. 17beta-HSD's are known as important mammalian enzymes which can be found in microorganisms, especially bacteria. The role of the fungal 17beta-HSD, on the other hand, is not yet clear. So far the only characterized fungal 17beta-HSD with hydroxysteroid dehydrogenase and carbonyl reductase activity has been found to be 17beta-HSD from the filamentous fungus Cochliobolus lunatus. Addictionally, constitutive 17beta-HSD activity has been to be widely distributed, also in Pleurotus ostreatus, indicating its possible common role in fungi. 16beta-HSD type 4 was found to be homologous to the multifunctional enzymes of peroxisomal fatty acids beta-oxidation in Candida tropicalis and Saharomices cerevisiae, indicating their possible common origin. In this sense the study of fungal beta-oxidation enzymes (beta-hydroxybutyryl CoA dehydrogenase) could be interesting from the point of view of the evolution of HSD. In my study the 17beta-HSD preparation from the fungus Pleurotus ostreatus was found to have a broad substrate specificity. Competition studies suggested the presence of two independent dehydrogenases, 17beta-HSD and beta-hydroxybutyryl CoA dehydrogenase. Dehydrogenase activities cound be separated by affinity chromatography. The purity of both enzymes was determined by separation on SDS PAGE and Western blotting. The presence of two independet dehydrogenases was laso indicated by inhibition studies. (Abstract truncated at 2000 characters.)
Deskriptorji		FUNGI 17-HYDROXYSTEROID DEHYDROGENASES CYTOSOL CHROMATOGRAPHY, THIN LAYER SPECTROPHOTOMETRY BINDING, COMPETITIVE HYDROXYBUTYRATE DEHYDROGENASE CHROMATOGRAPHY, GEL