Identification of the genes encoding enzymes involved in the early biosynthetic pathway of pteridines in Synechocystis sp. PCC 6803

• Published in: FEMS microbiology letters Vol. 176; no. 1; pp. 169 - 176
• Main Authors: Woong Lee, Soo, Woo Lee, Hee, Jae Chung, Hyun, Kim, Young-A, Jeong Kim, Yeon, Hahn, Yoonsoo, Hoon Chung, Jae, Shik Park, Young
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.1999
• Subjects: 6-Pyruvoyltetrahydropterine synthase; Cyanopterine; Dihydroneopterine aldolase; GTP cyclohydrolase I; Heterologous overexpression; Synechocystis sp. PCC 6803; 6-Pyruvoyltetrahydropterine synthase; GTP cyclohydrolase I; Synechocystis sp. PCC 6803; Heterologous overexpression; Cyanopterine; Dihydroneopterine aldolase
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1016/S0378-1097(99)00234-7

The biosynthetic pathway for the pteridine moiety of cyanopterine, as well as tetrahydrobiopterine, has been investigated in Synechocystis sp. PCC 6803. Open reading frames slr0426, slr1626, slr0078 and sll0330 of the organism putatively encoding GTP cyclohydrolase I, dihydroneopterine aldolase, 6-pyruvoyltetrahydropterine synthase and sepiapterine reductase, respectively, have been cloned into T7-based vectors for expression in Escherichia coli. The recombinant proteins have been purified to homogeneity and demonstrated to possess expected genuine activities except that of sll0330. Our result is the first direct evidence for the functional assignment of the open reading frames in Synechocystis sp. PCC 6803. Furthermore, the 6-pyruvoyltetrahydropterine synthase gene is demonstrated for the first time in prokaryotes. Based on the result, biosynthesis of cyanopterine is discussed.