scholarly journals The reaction of Pseudomonas aeruginosa cytochrome c oxidase with sodium metabisulphite (Short Communication)

1974 ◽  
Vol 139 (1) ◽  
pp. 273-276 ◽  
Author(s):  
Stephen R. Parr ◽  
Michael T. Wilson ◽  
Colin Greenwood
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Binding Sites ◽  
Short Communication ◽  
Sodium Metabisulphite

Spectrophotometric evidence is presented for the formation of a complex between metabisulphite and reduced Pseudomonas aeruginosa cytochrome c oxidase. The effects of metabisulphite on the recombination of CO with the reduced enzyme are discussed in terms of alternate binding sites for S2O52− and CO.

scholarly journals Cytochrome c-551 and azurin oxidation catalysed by Pseudomonas aeruginosa cytochrome oxidase. A steady-state kinetic study

1985 ◽  
Vol 230 (3) ◽  
pp. 797-805 ◽  
Author(s):  
M G Tordi ◽  
M C Silvestrini ◽  
A Colosimo ◽  
L Tuttobello ◽  
M Brunori
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Steady State ◽  
Cytochrome C ◽  
Cytochrome Oxidase ◽  
Binding Sites ◽  
Time Course ◽  
Product Inhibition ◽  
Inactive Form ◽  
Catalytically Active ◽  
The Stability

The kinetics of oxidation of azurin and cytochrome c-551 catalysed by Pseudomonas aeruginosa cytochrome oxidase were re-investigated, and the steady-state parameters were evaluated by parametric and non-parametric methods. At low concentrations of substrates (e.g. less than or equal to 50 microM) the values obtained for Km and catalytic-centre activity are respectively 15 +/- 3 microM and 77 +/- 6 min-1 for azurin and 2.15 +/- 0.23 microM and 66 +/- 2 min-1 for cytochrome c-551, in general accord with previous reports assigning to cytochrome c-551 the higher affinity for the enzyme and to azurin a slightly higher catalytic rate. However, when the cytochrome c-551 concentration was extended well beyond the value of Km, the initial velocity increased, and eventually almost doubled at a substrate concentration greater than or equal to 100 microM. This result suggests a ‘half-hearted’ behaviour, since at relatively low cytochrome c-551 concentrations only one of the two identical binding sites of the dimeric enzyme seems to be catalytically active, possibly because of unfavourable interactions influencing the stability of the Michaelis-Menten complex at the second site. When reduced azurin and cytochrome c-551 are simultaneously exposed to Ps. aeruginosa cytochrome oxidase, the observed steady-state oxidation kinetics are complex, as expected in view of the rapid electron transfer between cytochrome c-551 and azurin in the free state. In spite of this complexity, it seems likely that a mechanism involving a simple competition between the two substrates for the same active site on the enzyme is operative. Addition of a chemically modified and redox inactive form of azurin (Hg-azurin) had no effect on the initial rate of oxidation of either azurin and cytochrome c-551, but clearly altered the time course of the overall process by removing, at least partially, the product inhibition. The results lead to the following conclusions: (i) reduced azurin and cytochrome c-551 bind at the same site on the enzyme, and thus compete; (ii) Hg-azurin binds at a regulatory site, competing with the product rather than the substrate; (iii) the two binding sites on the dimeric enzyme, though intrinsically equivalent, display unfavourable interactions. Since water is the product of the reduction of oxygen, point (iii) has important implications for the reaction mechanism.

scholarly journals Circular-dichroic properties and secondary structure of Pseudomonas aeruginosa soluble cytochrome c oxidase

1984 ◽  
Vol 218 (3) ◽  
pp. 907-912 ◽  
Author(s):  
M G Tordi ◽  
M C Silvestrini ◽  
A Colosimo ◽  
S Provencher ◽  
M Brunori
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Secondary Structure ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Visible Region ◽  
Alpha Helix ◽  
Careful Analysis ◽  
Amino Acid Residues ◽  
Ferrocytochrome C ◽  
Significant Difference

The c.d. spectra of Pseudomonas aeruginosa cytochrome c oxidase in the oxidized state and the reduced state are reported in the visible- and u.v. absorption regions. In the visible region the comparison between the spectra of reduced cytochrome c oxidase and ferrocytochrome c-551 allows the identification of the c.d. bands mainly due to the d1 haem chromophore in cytochrome c oxidase. In the near-u.v. region the assignment of some of the observed peaks to the haem groups and to the aromatic amino acid residues is proposed. A careful analysis of the data in the far-u.v. region leads to the determination of the relative amounts of alpha-helix and beta-sheet in the enzyme, giving for the first time a picture of its secondary structure. A significant difference in this respect between the reduced and the oxidized species is observed and discussed in the light of similar conclusions reported by other workers.

scholarly journals Short Communication: The mitochondrial cytochrome c oxidase subunit I (COI) for identification of batoids collected from landed sites in Medan, Indonesia

2020 ◽  
Vol 21 (11) ◽  
Author(s):  
MUFTI SUDIBYO ◽  
Khairiza Lubis ◽  
ACHMAD FARAJALLAH ◽  
NISFA HANIM
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Short Communication ◽  
East Coast ◽  
Morphological Trait ◽  
Coi Gene ◽  
Mitochondrial Cytochrome ◽  
Landing Sites ◽  
Dna Fragment ◽  
North Sumatra

Abstract. Lubis K, Sudibyo M, Farajallah A, Hanim N. 2020. Short Communication: The mitochondrial cytochrome c oxidase subunit I (COI) for identification of batoids collected from landing sites in Medan, Indonesia. Biodiversitas 21: 5414-5421.  Batoids are member of Elsamoranch subclass which consist of many species. Most of batoids species are overexploited, especially in Medan Indonesia. Up to presents, the information about diversity of rays on the east coast of North Sumatra, Indonesia was very limited. Therefore, this research aimed to investigate the diversity of rays on the east coast of North Sumatra. We examined the morphological trait of 82 individuals of batoid from three landing sites on the east coast of North Sumatra, namely: Tanjung Balai, Belawan, and Percut, then identify its species based on determination key. After that, we collected pectoral muscle tissue from an individual in each species which successfully identified to extract its genomic DNA. Molecular based identification was carried out by using DNA fragment form COI gene. The successfully amplificated COI gene DNA fragment then was sequenced and analyzed. Based on morphological trait, we successfully identifying nine species of batoid, which is Maculabatis gerrardi, Gymnura poecilura, Dasyatis zugei, Brevitrygon heterura, Neotrygon kuhlii, Hemitrygon bennettii, Rhinobatos jimbaranensis, Rhinoptera javanica, and Taeniura lymma. The result of identification based on COI gene DNA fragment was in congruent with morphological-based identification based on data BLAST-N and genetic distance value within same species. The nucleotide diversity within same species ranged from 0-15 nucleotide variants.

scholarly journals The binding sites of Zn^ and Cd^ in bovine heart cytochrome c oxidase.

2001 ◽  
Vol 41 (supplement) ◽  
pp. S115
Author(s):  
K. Hirata ◽  
E. Yamashita ◽  
T. Tsukihara ◽  
K. Muramoto ◽  
S. Aonami ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Binding Sites ◽  
Bovine Heart

Similar carbon monoxide binding sites in bacterial cytochrome bo and mammalian cytochrome c oxidase

1993 ◽  
Vol 115 (8) ◽  
pp. 3390-3391 ◽  
Author(s):  
Jianling Wang ◽  
Yuan Chin Ching ◽  
Denis L. Rousseau ◽  
John J. Hill ◽  
Jon Rumbley ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Binding Sites ◽  
Cytochrome Bo ◽  
Carbon Monoxide Binding
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