Loeber G, Dworkin M B, Infante A, Ahorn H
Ernst Boehringer Institut, Vienna, Austria.
FEBS Lett. 1994 May 16;344(2-3):181-6. doi: 10.1016/0014-5793(94)00386-6.
Cytosolic NADP(+)-dependent malic enzyme (ME) from human tumor cells was characterized in detail and compared to ME from normal human tissues produced in recombinant E. coli. Kinetic properties, size as seen in SDS gels, and HPLC elution profiles of tryptic digests of human 'normal cell' ME and NADP(+)-ME from tumor cells were identical. Thus, NADP(+)-ME found in tumor cells does not constitute a tumor-specific isoform as suggested by other studies but is identical to the 'housekeeping protein' predominantly expressed in human liver and white adipose tissue.
对来自人肿瘤细胞的胞质NADP(+)-依赖性苹果酸酶(ME)进行了详细表征,并与重组大肠杆菌中产生的来自正常人组织的ME进行了比较。人“正常细胞”ME和肿瘤细胞的NADP(+)-ME的动力学特性、SDS凝胶中显示的大小以及胰蛋白酶消化产物的HPLC洗脱图谱均相同。因此,肿瘤细胞中发现的NADP(+)-ME并不像其他研究所暗示的那样构成肿瘤特异性同工型,而是与主要在人肝脏和白色脂肪组织中表达的“管家蛋白”相同。