Botanisches Institut der Universität München, Menzinger Str. 67, D-8000, München 19, Federal Republic of Germany.
Planta. 1978 Jan;140(3):239-44. doi: 10.1007/BF00390254.
A sulfotransferase isolated from the Cyanobacterium Synechococcus 6301 was found to be specific for 3'-phosphoadenosine-5'-phosphosulfate (PAPS). The molecular weight of this transferase has been estimated on a Sephadex-G-100 column to be about 58,000. The K m for PAPS was determined to be 20 μM. The pH optimum was 8.0. The thiol dithioerythritol was needed for activity; other thiols such as glutathione, cysteine, or mercaptoethanol did not catalyze this reaction. The transferase, however, could not react directly with the thiol. A heat-stable factor was needed in this reaction. This factor was purified by conventional techniques and its molecular weight was determined on a Sephadex-G-50 column to be about 11,500. The factor showed normal Michaelis-Menten behavior toward the PAPS-sulfotransferase. It has been identified as thioredoxin. The tranferase was inhibited by 3'-5'-ADP and 2'-5'-ADP; all other adenine-containing nucleotides such as 2'-AMP, 3'-AMP, 5'-AMP, ADP, and c-AMP did not influence this reaction.
从蓝藻集胞藻 6301 中分离出的一种磺基转移酶被发现对 3'-磷酸腺苷-5'-磷酸硫酸（PAPS）具有特异性。该转移酶的分子量在 Sephadex-G-100 柱上的估计约为 58000。PAPS 的 K m 值确定为 20 μM。最适 pH 值为 8.0。硫醇二硫赤藓糖醇是活性所必需的；其他硫醇，如谷胱甘肽、半胱氨酸或巯基乙醇，不能催化此反应。然而，转移酶不能直接与硫醇反应。该反应需要一种热稳定因子。该因子通过常规技术进行纯化，其分子量在 Sephadex-G-50 柱上的确定约为 11500。该因子对 PAPS-磺基转移酶表现出正常的米氏行为。它已被鉴定为硫氧还蛋白。转移酶被 3'-5'-ADP 和 2'-5'-ADP 抑制；所有其他含腺嘌呤的核苷酸，如 2'-AMP、3'-AMP、5'-AMP、ADP 和 c-AMP，均不影响此反应。
