« Previous AbstractThe mating-related loci sexM and sexP of the zygomycetous fungus Mucor mucedo and their transcriptional regulation by trisporoid pheromones    Next Abstract"Differential metabolism of pregnenolone by testicular homogenates of humans and two species of macaques. Lack of synthesis of the human sex pheromone precursor 5,16-androstadien-3 beta-ol in nonhuman primates" »

J Steroid Biochem

Title:		The mechanism of the synthesis of 16-androstenes in human testicular homogenates
Author(s):		Weusten JJ; Legemaat G; van der Wouw MP; Smals AG; Kloppenborg PW; Benraad T;
Address:		"Department of Medicine, St. Radboud Hospital, University of Nijmegen, The Netherlands"
Journal Title:		J Steroid Biochem
Year:		1989
Volume:		32
Issue:		5
Page Number:		689 - 694
DOI:		10.1016/0022-4731(89)90513-x
ISSN/ISBN:		0022-4731 (Print) 0022-4731 (Linking)
Abstract:		"The biochemical pathway leading to the 16-unsaturated C19 steroids--known as sex pheromone (precursors) in pig and man--is still a matter of dispute. In the 16-ene-synthetase process, via which 5,16-androstadien-3 beta-ol (ADL) or 4,16-androstadien-3-one (ADN) are biosynthesized from pregnenolone (P5) or progesterone (P4), a number of 2 or even 3 step conversions have been suggested in porcine tests, including 20 beta-reduction, 21-hydroxylation and 16,17-dehydrogenation. Studying the 16-ene-synthetase reaction in human testicular homogenates, we adduced evidence for the hypothesis that ADL is synthesized from P5 in a single step, not requiring separate intermediates. Our proposal for the 16-ene-synthetase mechanism also explains why, at least in our hands, synthesis of ADL is always accompanied by co-synthesis of its satellite 5-androstene-3 beta,17 alpha-diol (epiA5): both steroids are synthesized as a mere consequence of the fact that the proposed elimination and substitution reactions for the synthesis of ADL and epiA5, respectively, are competitive processes"
Keywords:		"Androstenes/*biosynthesis Androstenols/biosynthesis Humans In Vitro Techniques Male Models, Chemical Oxidoreductases/*metabolism Pregnenolone/metabolism Testis/*metabolism;"
Notes:		"MedlineWeusten, J J Legemaat, G van der Wouw, M P Smals, A G Kloppenborg, P W Benraad, T eng England 1989/05/01 J Steroid Biochem. 1989 May; 32(5):689-94. doi: 10.1016/0022-4731(89)90513-x"