Robertson I G, Jensson H, Guthenberg C, Tahir M K, Jernström B, Mannervik B
Biochem Biophys Res Commun. 1985 Feb 28;127(1):80-6. doi: 10.1016/s0006-291x(85)80128-5.
Cytosolic GSH transferases have been purified from rat lung by affinity chromatography followed by chromatofocusing. On the criteria of order of elution, substrate specificity, apparent subunit Mr, sensitivity to inhibitors, and reaction with antibodies, transferase subunits equivalent to subunits 2, 3, and 4, in the binary combinations occurring in liver, were identified. However, subunit 1 (and therefore transferases 1-1 and 1-2) was not detected. The most conspicuous difference is the presence in lung of a new form, eluting at pH 8.7, which is not detected in rat liver. This isoenzyme (transferase "pH 8.7") is characterized by its low apparent subunit Mr and high efficiency in the conjugation of glutathione with anti-benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide, considered the ultimate carcinogen of benzo(a)-pyrene.
通过亲和层析继以色谱聚焦法，已从大鼠肺中纯化出胞质谷胱甘肽转移酶。根据洗脱顺序、底物特异性、表观亚基分子量、对抑制剂的敏感性以及与抗体的反应等标准，鉴定出了与肝脏中二元组合形式的亚基2、3和4相当的转移酶亚基。然而，未检测到亚基1（因此也未检测到转移酶1-1和1-2）。最显著的差异是在肺中存在一种在pH 8.7洗脱的新形式，而在大鼠肝脏中未检测到。这种同工酶（转移酶“pH 8.7”）的特征在于其低表观亚基分子量以及在谷胱甘肽与抗苯并(a)芘-7,8-二氢二醇-9,10-环氧化物（被认为是苯并(a)芘的最终致癌物）结合方面的高效率。
