Wu C S, Chuang N N
Division of Biochemistry and Molecular Science, Academia Sinica, Nankang, Taipei, Taiwan.
J Exp Zool. 1996 Aug 1;275(5):346-54. doi: 10.1002/(SICI)1097-010X(19960801)275:5<346::AID-JEZ3>3.0.CO;2-P.
Protein farnesyltransferase from the eyes of Penaeus japonicus farnesylates predominantly H-ras-specific carboxyl termini, with the sequence CVLS, but not the K-ras-specific sequence CVIM or the protein geranylgeranyltransferase-specific sequence CAIL. The purified protein farnesyltransferase from shrimp was found by immunoblotting and polyacrylamide gel electrophoresis under denaturing conditions to consist of subunits of Mr 49,000 and Mr 48,000. Since the active protein farnesyltransferase was found to have a relative mass of 100,000, the purified enzyme was deduced to be a heterodimer. The enzyme had an optimal pH of 6 and a K(m) of 14 +/- 1 microM with the synthetic peptide RTRCVLSH as the substrate. The enzyme was activated by Mn+2 and Mg+2 but inhibited by Ca+2 ions.
日本对虾眼中的蛋白质法尼基转移酶主要法尼基化具有CVLS序列的H-ras特异性羧基末端,但不作用于具有CVIM序列的K-ras或具有CAIL序列的蛋白质香叶基香叶基转移酶特异性序列。在变性条件下通过免疫印迹和聚丙烯酰胺凝胶电泳发现,从虾中纯化的蛋白质法尼基转移酶由分子量为49,000和48,000的亚基组成。由于发现活性蛋白质法尼基转移酶的相对质量为100,000,因此推断纯化的酶是一种异二聚体。该酶的最适pH为6,以合成肽RTRCVLSH为底物时的K(m)为14±1 microM。该酶被Mn+2和Mg+2激活,但被Ca+2离子抑制。