pregnenolone + PAPS => pregnenolone sulfate + PAP EC Number: 2.8.2.15 Edited: D'Eustachio, P, 2006-03-11 18:40:17 Pubmed11457664 Pubmed12145317 Reactome Database ID Release 43176517 Reactome, http://www.reactome.org ReactomeREACT_6805 Reviewed: D'Eustachio, P, 2008-05-28 08:30:54 The sulfonation of pregnenolone is catalyzed by both the a and b isoforms of SULT2B1, although the a isoform is more active in assays in vitro (Fuda et al. 2002; Meloche and Falany 2001).