Increasing the electron-transfer ability of Cyanidioschyzon merolae ferredoxin by a one-point mutation – A high resolution and Fe-SAD phasing crystal structure analysis of the Asp58Asn mutant

• Published in: Biochemical and biophysical research communications Vol. 436; no. 4; pp. 736 - 739
• Main Authors: Ueno, Yuko, Matsumoto, Takashi, Yamano, Akihito, Imai, Takeo, Morimoto, Yukio
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 12-07-2013
• Subjects: 60 APPLIED LIFE SCIENCES; ALGAE; AMINO ACIDS; Asparagine - genetics; Aspartic Acid - genetics; CRYSTAL STRUCTURE; Crystallography, X-Ray; Cyanidioschyzon merolae; ELECTRON TRANSFER; Electron transfer ability; Electron Transport; FERREDOXIN; Ferredoxins - chemistry; Ferredoxins - genetics; Ferredoxins - metabolism; GENE MUTATIONS; High resolution analysis; Models, Molecular; MUTANTS; Mutation; NADP; PH VALUE; Plant type ferredoxin; Protein Conformation; Rhodophyta - metabolism; X-ray analysis; High resolution analysis; X-ray analysis; Plant type ferredoxin; Electron transfer ability
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2013.06.029

•A single amino acid change on the ferredoxin surface affects electron transfer.•Precise positions of amide atoms were located utilizing no prior structural data.•Ultra high resolution and SAD phasing may be used for bias-free model building.
Cyanidioschyzon merolae (Cm) is a single cell red algae that grows in rather thermophilic (40–50°C) and acidic (pH 1–3) conditions. Ferredoxin (Fd) was purified from this algae and characterized as a plant-type [2Fe–2S] Fd by physicochemical techniques. A high resolution (0.97Å) three-dimensional structure of the CmFd D58N mutant molecule has been determined using the Fe-SAD phasing method to clarify the precise position of the Asn58 amide, as this substitution increases the electron-transfer ability relative to wild-type CmFd by a factor of 1.5. The crystal structure reveals an electro-positive surface surrounding Asn58 that may interact with ferredoxin NADP+ reductase or cytochrome c.