Author/Editor     Lanišnik-Rižner, T; Stojan, J; Adamski, J
Title     Searching for the physiological function of 17beta-hydroxysteroid dehydrogenase from the fungus Cochliobolus lunatus: studies of substrate specificity and expression analysis
Type     članek
Source     Mol Cell Endocrinol
Vol. and No.     Letnik 171
Publication year     2001
Volume     str. 193-8
ISSN     0303-7207
Language     eng
Abstract     17beta-hydroxysteroid dehydrogenase from the filamentous fungus Cochliobolus lunatus (17beta-HSDcI) has recently been characterized. Since its function is still unclear, we performed substrate specificity studies to obtain some indications about its physiological function. Different steroids were studied as putative substrates of recombinant 17beta-HSDcl, androgens and estrogens, brassinosteroids, and the fungal steroid herbarulid. Among these androgens and estrogens were most efficiently converted. The following substrates in decreasing order were best reduced: 4-estrene-3,17-dione, 5alpha-androstane-3,17-dione, 4-androstene-3,17-dione and estrone. Two typical inhibitors were tested: carbenoxolone - a representative inhibitor of the SDR family and quercetin - a diagnostic inhibitor of carbonyl reductases. Among these two quercetin was more efficient. Expression studies revealed that 17beta-HSDcl is mainly expressed in the stationary phase of growth indicating its possible involvement in secondary metabolism.
Descriptors     ASCOMYCETES
17-HYDROXYSTEROID DEHYDROGENASES
SUBSTRATE SPECIFICITY
ANDROGENS
ESTROGENS
5-ANDROSTANE-3,17-DIOL
ESTRENES
ANDROSTENEDIONE
ESTRONE
ESTRADIOL
CARBENOXOLONE
QUERCETIN
BLOTTING, NORTHERN