tailieunhanh - Báo cáo khoa học: Geranylgeranyl reductase involved in the biosynthesis of archaeal membrane lipids in the hyperthermophilic archaeon Archaeoglobus fulgidus

Complete saturation of the geranylgeranyl groups of biosynthetic interme-diates of archaeal membrane lipids is an important reaction that confers chemical stability on the lipids of archaea, which generally inhabit extreme conditions. An enzyme encoded by theAF0464gene of a hyperthermophi-lic archaeon, Archaeoglobus fulgidus, which is a distant homologue of plant geranylgeranyl reductases and an A. | ỊFEBS Journal Geranylgeranyl reductase involved in the biosynthesis of archaeal membrane lipids in the hyperthermophilic archaeon Archaeoglobus fulgidus Motomichi Murakami1 Kyohei Shibuya2 Toru Nakayama2 Tokuzo Nishino2 Tohru Yoshimura1 and Hisashi Hemmi1 1 Department of Applied Molecular Bioscience Graduate Schoolof BioagriculturalSciences Nagoya University Aichi Japan 2 Department of Biomolecular Engineering Graduate Schoolof Engineering Tohoku University Miyagi Japan Keywords archaea geranylgeranyl reductase isoprenoid lipid oxidoreductase Correspondence H. Hemmi Department of Applied Molecular Bioscience Graduate Schoolof Bioagricultural Sciences Nagoya University Furo-cho Chikusa-ku Nagoya Aichi 464-8601 Japan Fax 81 52 7894120 Tel 81 52 7894134 E-mail hhemmi@ Received 27 September 2006 revised 29 November 2006 accepted 5 December 2006 doi Complete saturation of the geranylgeranyl groups of biosynthetic intermediates of archaeal membrane lipids is an important reaction that confers chemical stability on the lipids of archaea which generally inhabit extreme conditions. An enzyme encoded by the AF0464 gene of a hyperthermophi-lic archaeon Archaeoglobus fulgidus which is a distant homologue of plant geranylgeranyl reductases and an A. fulgidus menaquinone-specific prenyl reductase Hemmi H Yoshihiro T Shibuya K Nakayama T Nishino T 2005 J Bacteriol 187 1937-1944 was recombinantly expressed and purified and its geranylgeranyl reductase activity was examined. The radio HPLC analysis indicated that the flavoenzyme which binds FAD noncova-lently showed activity towards lipid-biosynthetic intermediates containing one or two geranylgeranyl groups under anaerobic conditions. It showed a preference for 2 3-di-O-geranylgeranylglyceryl phosphate over 3-O-geranyl-geranylglyceryl phosphate and geranylgeranyl diphosphate in vitro and did not reduce the prenyl group of respiratory quinones in Escherichia coli cells. The .