tailieunhanh - Báo cáo khoa học: Identification of a novel thyroid hormone-sulfating cytosolic sulfotransferase, SULT1 ST5, from zebrafish Molecular cloning, expression, characterization and ontogenic study

By employing RT-PCR in conjunction with 3¢-RACE, a full-length cDNA encoding a novel zebrafish cytosolic sulfotransferase (SULT) was cloned and sequenced. Sequence analysis revealed that this zebrafish SULT (desig-nated SULT1 ST5) is, at the amino acid sequence level, close to 50% identical to human and dog SULT1B1 (thyroid hormone SULT). A recombinant form of zebrafish SULT1 ST5 was expressed using the pGEX-2TK bacterial expression system and purified from transformed BL21 (DE3) cells. | iFEBS Journal Identification of a novel thyroid hormone-sulfating cytosolic sulfotransferase SULT1 ST5 from zebrafish Molecular cloning expression characterization and ontogenic study Shin Yasuda A. Pavan Kumar Ming-Yih Liu Yoichi Sakakibara Masahito Suiko Lanzhuang Chen and Ming-Cheh Liu BiomedicalResearch Center The University of Texas Health Center Tyler USA Keywords molecular cloning sulfotransferase SULT1 thyroid hormone zebrafish Correspondence . Liu BiomedicalResearch Center The University of Texas Health Center 11937 . Highway 271 Tyler TX 75708 USA Fax 1 903 877 2863 Tel 1 903 877 2862 E-mail Received 7 February 2005 revised 20 April 2005 accepted 25 May 2005 doi By employing RT-PCR in conjunction with 3 -RACE a full-length cDNA encoding a novel zebrafish cytosolic sulfotransferase SULT was cloned and sequenced. Sequence analysis revealed that this zebrafish SULT designated SULT1 ST5 is at the amino acid sequence level close to 50 identical to human and dog SULT1B1 thyroid hormone SULT . A recombinant form of zebrafish SULT1 ST5 was expressed using the pGEX-2TK bacterial expression system and purified from transformed BL21 DE3 cells. Purified zebrafish SULT1 ST5 migrated as a 34 kDa protein and displayed substrate specificity for thyroid hormones and their metabolites among various endogenous compounds tested. The enzyme also exhibited sulfating activities toward some xenobiotic phenolic compounds. Its pH optima were and with 3 3 5-triiodo-L-thyronine l-T3 as substrate and with b-naphthol as substrate. Kinetic constants of the enzyme with thyroid hormones and their metabolites as substrates were determined. Quantitative evaluation of the regulatory effects of divalent metal cations on the L-T3-sulfating activity of SULT1 ST5 revealed that Fe2 Hg2 Co2 Zn2 Cu2 Cd2 and Pb2 exhibited dramatic inhibitory effects whereas Mn2 showed a significant stimulation. Developmental stage-dependent .