Publications by authors named "Shin-ichi Mikami"

Article Synopsis
  • Pseudomonas aeruginosa cytochrome c(551) features a unique polypeptide loop near its heme that is stabilized by a specialized hydrogen bond network involving Ser52 and Met61.
  • The research examined the effects of S52N and S52G mutations on the protein's structure and redox function, finding that S52N minimally impacted function while S52G produced more significant changes.
  • The study concluded that Ser52's role is crucial for maintaining the protein's stability, with Asn52 in S52N maintaining similar functionality, whereas the structural shift in S52G leads to altered protein function.
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Careful scrutiny of the protein interior of Hydrogenobacter thermophilus cytochrome c(552) (HT) on the basis of its X-ray structure [Travaglini-Allocatelli, C., Gianni, S., Dubey, V.

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A male ferret, which was purchased from abroad at 9 months of age, had shown significant weight loss starting at 13 months of age. The ferret subsequently showed decreasing motor activity and recumbency and was euthanized at 14 months of age. At necropsy, a white, quail egg-sized mass was found in the mesentery.

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In Hydrogenobacter thermophilus cytochrome c(552), an electrostatic interaction between Lys8 and Glu68 in the N- and C-terminal helices, respectively, stabilizes its protein structure [Travaglini-Allocatelli, C., Gianni, S., Dubey, V.

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The thermodynamic properties of the redox potentials (E(m)) of Pseudomonas aeruginosa cytochrome c(551) (PA) and its mutants possessing a variety of pK(a) values for the heme 17-propionic acid side chain, which ranged from approximately 5 to approximately 8, have been investigated to elucidate the role of ionization of the heme side chain in the E(m) control. Since the pK(a) values of the heme 17-propionic acid side chains of the oxidized and reduced forms of PA are 5.9 +/- 0.

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In order to elucidate the molecular mechanisms responsible for the apparent nonlinear behavior of the temperature dependence of the redox potential of Hydrogenobacter thermophilus cytochrome c552 [Takahashi, Y., Sasaki, H., Takayama, S.

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Thermophile Hydrogenobacter thermophilus cytochrome c(552) (HT) is a stable protein with denaturation temperatures (T(m)) of 109.8 and 129.7 degrees C for the oxidized and reduced forms, respectively [Uchiyama, S.

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Pseudomonas aeruginosa cytochrome c(551) and a series of its mutants exhibiting various thermostabilities have been studied by paramagnetic (1)H NMR and cyclic voltammetry in an effort to elucidate the molecular mechanisms responsible for control of the redox potentials (E degrees ') of the proteins. The study revealed that the E degrees ' value of the protein is regulated by two molecular mechanisms operating independently of each other. One is based on the Fe-Met coordination bond strength in the protein, which is determined by the amino acid side chain packing in the protein, and the other on the pK(a) of the heme 17-propionic acid side chain, which is affected by the electrostatic environment.

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