2g18

Crystal Structure of Nostoc sp. 7120 phycocyanobilin:ferredoxin oxidoreductase (PcyA) Apoprotein

spinqualitylabelsall models 2g18, resolution 2.50Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 2g18 is a 12 chain structure with sequence from Anabaena sp.. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: CA Gene: pcyA (Anabaena sp.) Activity: Phycocyanobilin:ferredoxin oxidoreductase, with EC number 1.3.7.5 Resources: FirstGlance, OCA, RCSB, PDBsum Function [PCYA_ANASP] Catalyzes the four-electron reduction of biliverdin IX-alpha (2-electron reduction at both the A and D rings); the reaction proceeds via an isolatable 2-electron intermediate, 181,182-dihydrobiliverdin. Upon overexpression in E.coli with PCB:ferredoxin oxidoreductase, CpeS and either CpcB or PecB permits synthesis of phycocyanin-coupled CpcB or PecB. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed The X-ray crystal structure of the substrate-free form of phycocyanobilin (PCB)-ferredoxin oxidoreductase (PcyA; EC 1.3.7.5) from the cyanobacterium Nostoc sp. PCC7120 has been solved at 2.5 A resolution. A comparative analysis of this structure with those recently reported for substrate-bound and substrate-free forms of PcyA from the cyanobacterium Synechocystis sp. PCC6803 (Hagiwara et al. (2006) Proc. Natl. Acad. Sci. U.S.A. 103, 27-32; Hagiwara et al. (2006) FEBS Lett. 580, 3823-3828) provides a compelling picture of substrate-induced changes in the PcyA enzyme and the chemical basis of PcyA's catalytic activity. On the basis of these structures and the biochemical analysis of site-directed mutants of Nostoc PcyA, including mutants reported in recent studies (Tu et al. (2006) J. Biol. Chem. 281, 3127-3136) as well as mutants described in this study, a revised mechanism for the PcyA-mediated four-electron reduction of biliverdin IXalpha to 3E/3Z-phycocyanobilin via enzyme-bound bilin radical intermediates is proposed. The mechanistic insight of these studies, along with homology modeling, have provided new insight into the catalytic mechanisms of other members of the ferredoxin-dependent bilin reductase family that are widespread in oxygenic photosynthetic organisms. Insight into the radical mechanism of phycocyanobilin-ferredoxin oxidoreductase (PcyA) revealed by X-ray crystallography and biochemical measurements.,Tu SL, Rockwell NC, Lagarias JC, Fisher AJ Biochemistry. 2007 Feb 13;46(6):1484-94. Epub 2007 Jan 17. PMID:17279614 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA