Misa Masanari

Learn More
Shewanella species live widely in deep-sea and shallow-water areas, and thus grow piezophilically and piezosensitively. Piezophilic and psychrophilic Shewanella benthica cytochrome c 5 (SB cytc 5) was the most stable against guanidine hydrochloride (GdnHCl) and thermal denaturation, followed by less piezophilic but still psychrophilic Shewanella violacea(More)
Hyperthermophilic Aquifex aeolicus cytochrome c(555) (AA c(555)) exceptionally folds even in the apo state, unlike general cytochromes c including mesophilic Pseudomonas aeruginosa cytochrome c(551) (PA c(551)), which is structurally homologous to AA c(555) in the holo state. Here we hypothesized that the exceptional apo AA c(555) folding can be attributed(More)
Cytochrome c' (SACP) from mesophilic Shewanella amazonensis, growing optimally at 37 °C, was thermally more stable than cytochrome c' (AVCP) from mesophilic Allochromatium vinosum, growing optimally at 25 °C. In contrast, SACP was less stable than cytochrome c' (PHCP) from thermophilic Hydrogenophilus thermoluteolus, growing optimally at 52 °C. Although(More)
Sequence analysis indicated that thermophilic Hydrogenophilus thermoluteolus cytochrome c' (PHCP) and its mesophilic homolog, Allochromatium vinosum cytochrome c' (AVCP), closely resemble each other in a phylogenetic tree of the cytochrome c' family, with 55% sequence identity. The denaturation temperature of PHCP was 87 °C, 35 °C higher than that of AVCP.(More)
Apo-cytochomes c without heme are usually unstructured. Here we showed that apo-form of thermophilic Hydrogenophilus thermoluteolus cytochrome c' (PHCP) was a monomeric protein with high helix content. Apo-PHCP was thermally stable, possibly due to the hydrophobic residues and ion pairs. PHCP is the first example of a structured apo-cytochrome c', which(More)
Cytochrome c₅ of pressure-sensitive Shewanella livingstonensis (SL cytc₅) exhibits lower thermal stability than a highly homologous counterpart of pressure-tolerant Shewanella violacea. This stability difference is due to an enthalpic effect that can be attributed to the amino acid residue at position 50 (Leu or Lys). These cytc₅ proteins are appropriate(More)
Monomeric cytochrome c5 from deep-sea piezophilic Shewanella violacea (SVcytc5) was stable against heat and denaturant compared with the homologous protein from shallow-sea piezo-sensitive Shewanella livingstonensis (SLcytc5). Here, the SVcytc5 crystal structure revealed that the Lys-50 side chain on the flexible loop formed a hydrogen bond with heme(More)
Thermophilic Hydrogenophilus thermoluteolus cytochrome c' (PHCP) exhibits higher thermal stability than a mesophilic counterpart, Allochromatium vinosum cytochrome c' (AVCP), which has a homo-dimeric structure and ligand-binding ability. To understand the thermal stability mechanism and ligand-binding ability of the thermally stable PHCP protein, the(More)
Hydrogenophilus is a thermophilic, facultative chemoautotroph, which lives prevalently in high temperature geothermal niches. Despite the environmental distribution, little is known about its oxidative phosphorylation. Here, we show that inverted membrane vesicles derived from Hydrogenophilus thermoluteolus cells autotrophically cultivated with H2 formed a(More)