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标题：Isolation, partial purification, and characterization of a novel petromyzonol sulfotransferase from Petromyzon marinus (lamprey) larval liver
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作者：K. V. Venkatachalam ; Domingo E. Llanos ; Kristophe J. Karami 等
期刊名称：JLR Papers In Press
印刷版ISSN：0022-2275
电子版ISSN：1539-7262
出版年度：2004
卷号：45
期号：3
页码：486-495
DOI：10.1194/jlr.M300346-JLR200
语种：English
出版社：American Society for Biochemistry and Molecular Biology
摘要：We have isolated, partially purified, and characterized the 5α–petromyzonol (5α-PZ), (5α-cholan- 3α, 7α, 12α, 24-tetrahydroxy-) sulfotransferase (PZ-SULT) from larval lamprey liver. Crude liver extracts exhibited a PZ-SULT activity of 0.9120 pmol/min/mg in juvenile and 12.62 pmol/min/mg in larvae. Using crude larval liver extracts and various 5 β-cholan substrates and allocholic acid there was negligible activity, however, with 5α-PZ and 3-keto-5α-PZ the SULT activity was 231.5 pmol/min/mg and 180.8 pmol/min/mg respectively. This established that the sulfotransferase of lamprey larval liver extracts prefers (5 α) substrates and it is selective for hydroxyl at C-24. PZ-SULT was purified through various chromatography procedures. Partially purified PZ-SULT exhibited a pH optimum of 8.0, a temperature optimum of 22°C, and activity was linear for 1h. PZ-SULT exhibited a K _m of 2.5 μM for PAPS and a K _m of 8 μM for PZ. The affinity purified peak PZ-SULT exhibited a specific activity of 2,038 pmol/min/mg. The peak protein upon SDS-PAGE, correlated to an Mw 47 kDa. Photoaffinity labeling with PAP³⁵S, specifically crosslinked the 47 kDa protein, further confirming the identity of PZ-SULT. Partial amino acid sequencing of the putative 47 kDa PZ-SULT protein yielded a peptide sequence (M)SISQAVDAAFXEI, which possessed an overall (∼35–40%) homology with mammalian SULT2B1a.