Structural and functional insights into thermally stable cytochrome c′ from a thermophile

• DOI: 10.1002/pro.3120
• Publication Date: 2017-01-18T09:46:18Z
• Authors: Sotaro Fujii; Hiroya Oki; Kazuki Kawahara; Daisuke Yamane; Masaru Yamanaka; Takahiro Maruno; Yuji Kobayashi; Misa Masanari; Satoshi Wakai; Hirofumi Nishihara; Tadayasu Ohkubo; Yoshihiro Sambongi
• Keywords: Hemeprotein

Thermophilic Hydrogenophilus thermoluteolus cytochrome c' (PHCP) exhibits higher thermal stability than a mesophilic counterpart, Allochromatium vinosum (AVCP), which has homo-dimeric structure and ligand-binding ability. To understand the mechanism ability of thermally stable PHCP protein, crystal was first determined. It formed structure, main chain root mean square deviation (rmsd) value between AVCP being 0.65 Å. In six specific residues appeared to strengthen heme-related subunit-subunit interactions, were not conserved in structure. variants having altered interactions more severely destabilized ones interactions. The further revealed channel penta-coordinated heme, as observed protein. A spectroscopic study clearly showed that some ligands bound is concluded dimeric from thermophile effectively stabilized through with conservation ability.We report X-ray thermophilic thermoluteolus. high attributed confirmed by mutagenesis study. examined spectrophotometry. acquired This furthers understanding function cytochromes c.