Catalysis of Lyase-isomerase PecE/PecF for Seve ral Apophycobiliproteins
藻红蓝蛋白裂合异构酶对几种脱辅基藻胆蛋白的催化作用

Phycoerythrocyanin(PEC) lyase-isomerase PecE/PecF from Mastigocladus laminosus is the specific enzyme for biosynthesis of PEC alpha-subunit(alpha-PEC). In this work, the specificity of PecE/PecF on substrate apoproteins was reported. PecE/PecF could catalyse the reconstitution of phycocyanobilin(PCB) with apoproteins of alpha-PEC from two different subspecies of Mastigocladus laminosus, as well the site-directed mutated apoprotein of alpha-PEC with Trp at 128 to Phe in vitro, but could not catalyse the reconstitution of PCB with apoprotein of phycocyanin alpha-subunit(alpha-CPC) from Mastigocladus laminosus. The surfactant Triton X-100 had no effect for the reconstitution of alpha-PEC, while it could improve the reconstitution of PCB with apoprotein of alpha-CPC.