Author/Editor		Matis, Maja
Title		Modern approaches for identification and characterization of enzymes that convert steroids in fungi Hortaea werneckii and Pleurotus ostreatus
Translated title		Sodobni pristopi za identifikacijo in karakterizacijo encimov, ki v glivah Hortaea werneckii in Pleurotus ostreatus pretvarajajo steroide
Type		monografija
Place		Ljubljana
Publisher		Univerza v Ljubljani, Medicinska fakulteta
Publication year		2005
Volume		str. 113
Language		eng
Abstract		Fungi are ubiquitous organisms that can be found in various ecological niches, and as such they are able to adapt to different conditions that are typical of specific environments. Throughout evolution, they have developed a variety of mechanisms for this adaptation. Among these, their ability to transform steroids is of great interest. As little is known concerning the general responses of yeast and fungi to exogenous steroids, we have studied the interactions between these organisms and steroids. Since every adaptation to new conditions requires a whole set of different proteins, including those that are newly synthesized as well as those constitutive, we have used two approaches in our study: a global approach and a targeted approach. With the first, we wanted to identify the proteins that are induced in the presence of progesterone, the identities of which could provide new insights into the steroid response. To reveal the roles of the constitutive steroid-transforming enzymes, which are widely distributed among fungi and yeast, we used the second approach. For a comparison of the protein expression profiles of the progesterone-stimulated samples versus the control samples in the halophilic black yeast Hortaea werneckii, fluorescent two-dimensional differential gel electrophoresis (2D-DIGE) technology was used. The results showed the up-regulation of twenty proteins. As the genome of H. werneckii has not yet been sequenced, de novo sequencing had to be carried out. The identities of the proteins from this study, however, are in a good agreement with the biological functions that have previously been postulated for them, namely growth inhibition of yeast cells by steroids. In this context, the over-expression of the members of the SIt2 kinase signalling pathway indicates the action of progesterone. The importance of cell signalling in steroid responses was additionally demonstrated by an analysis of the phosphoproteome. (Abstract truncated at 2000 characters)
Descriptors		BASIDIOMYCETES PROGESTERONE AMINO ACID SEQUENCE SIGNAL TRANSDUCTION 17-HYDROXYSTEROID DEHYDROGENASES PROTEINS ELECTROPHORESIS, GEL, TWO-DIMENSIONAL PHOSPHORYLATION CYTOSOL SPECTRUM ANALYSIS, MASS