Probing Nucleotide Binding Site of Phenol Sulfotransferase by Site-Directed Mutangenesis at Lys-65 and Arg-68

• Main Authors: Tsan, Shu Ging, 詹淑菁
• Other Authors: Yuh-Shyong Yang
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/27421645456539039477

碩士 === 國立交通大學 === 生物科技研究所 === 86 === Sulfation in biological system plays important roles in regulating structure and function of macromolecules, availability of hormones and neurotransmitters, activation and deactivation of xenobiotics, and elimination of end products of catabolism. Sulfotransferase catalyze all the known biological sulfation which involves the transfer of a sulfuryl group from a common sulfate donor, a nucleotide called 3'-phospho adenosine 5'-phosphosulfate (PAPS). Another nucleotide, 3'-phospho adenosine 5'-phosphate (PAP)A double mutant (K65E+R68G) exhibits over 500-fold increase in Km for PAP with Vmax remained the same （6）. Adenosine 5'-monophosphate (AMP), Adenosine 2', 3'-cycliphosphate 5'-phosphate and Adenosine 2', 5'-bisphosphate were shown to replace PAP as cofactor for sulfuryl group transfer（24）. However neither mutant's Km nor Vmax of these nucleotides differ significantly with that of wild type's. According to the study of Yoshimitsu, et al, Lys 65 and Arg68 were not involved in enzyme PAP binding site. But w