scholarly journals Haem ligands of the ferricytochrome c of Ustilago sphaerogena

1974 ◽  
Vol 139 (3) ◽  
pp. 547-553
Author(s):  
Serge N. Vinogradov ◽  
Kamal G. Bitar ◽  
Steven Lowenkron
Keyword(s):  
Cytochrome C ◽  
Equilibrium Constants ◽  
Side Chain ◽  
Neutral Ph ◽  
Methionine Residue ◽  
Single Polypeptide Chain ◽  
Ferricytochrome C ◽  
Nadh Cytochrome ◽  
Single Polypeptide ◽  
Ph Range

The mammalian-type cytochrome c of the basidiomycete Ustilago sphaerogena contains in a single polypeptide chain of 107 residues, two histidine residues located at positions 18 and 33, and one methionine residue situated at position 80 (Bitar et al., 1972). The reaction of Ustilago ferricytochrome c with bromoacetate at neutral pH resulted in the modification of histidine-33, but not of histidine-18 or of the invariant methionine residue. The activities of Ustilago cytochrome c with mitochondrial cytochrome c oxidase and with NADH–cytochrome c reductase were unaltered by the modification. The equilibrium constants for the formation of low-spin complexes of the ferrihaem octapeptide of horse cytochrome c (residues 14–21, including the haem bound covalently to cysteines 14 and 17) with imidazole, N2-acetylhistidine and monocarboxymethyl derivatives of N2-acetylhistidine were determined spectrophotometrically. Alkylation of the imidazole side-chain group of N2-acetylhistidine resulted in a marked decrease in its ability to form low-spin ferrihaem complexes. These results indicate that in Ustilago ferricytochrome c in solution histidine-33 is not involved in the central co-ordination complex. Since side-chain groups of residues other than histidine and methionine do not appear to be involved in the central complexes of other mammalian-type cytochromes c (Hettinger & Harbury, 1964, 1965; Myer & Harbury, 1965) it is likely that in Ustilago ferricytochrome c in solution at neutral pH, the side-chain groups of histidine-18 and methionine-80 are involved in the central co-ordination complex. The latter is stable over the pH range 2.6–8.4.

scholarly journals The amino acid sequence of cytochrome c-555 from the methane-oxidizing bacterium Methylococcus capsulatus

1986 ◽  
Vol 233 (2) ◽  
pp. 333-337 ◽  
Author(s):  
R P Ambler ◽  
H Dalton ◽  
T E Meyer ◽  
R G Bartsch ◽  
M D Kamen
Keyword(s):  
Amino Acid ◽  
Cytochrome C ◽  
Amino Acid Sequence ◽  
Polypeptide Chain ◽  
Cysteine Residues ◽  
British Library ◽  
Methylococcus Capsulatus ◽  
Methionine Residue ◽  
Single Polypeptide Chain ◽  
Single Polypeptide

The amino acid sequence of the cytochrome c-555 from the obligate methanotroph Methylococcus capsulatus strain Bath (N.C.I.B. 11132) was determined. It is a single polypeptide chain of 96 residues, binding a haem group through the cysteine residues at positions 19 and 22, and the only methionine residue is a position 59. The sequence does not closely resemble that of any other cytochrome c that has yet been characterized. Detailed evidence for the amino acid sequence of the protein has been deposited as Supplementary Publication SUP 50131 (12 pages) at the British Library Lending Division, Boston Spa, West Yorkshire LS23 7BQ, U.K., from whom copies are available on prepayment.

The Amino Acid Sequence of Cytochrome c-553 from the Chrysophycean Alga Monochrysis lutheri

1972 ◽  
Vol 50 (12) ◽  
pp. 1311-1325 ◽  
Author(s):  
M. V. Laycock
Keyword(s):  
Amino Acid ◽  
Cytochrome C ◽  
Amino Acid Sequence ◽  
Polypeptide Chain ◽  
Photosynthetic Apparatus ◽  
Amino Acid Residues ◽  
Unicellular Alga ◽  
Electron Carrier ◽  
Single Polypeptide Chain ◽  
Single Polypeptide

The amino acid sequence of cytochrome c-553, an electron carrier in the photosynthetic apparatus of the unicellular alga Monochrysis lutheri, has been determined. The protein consists of a single polypeptide chain of 83 amino acid residues. The sequence shows homology with mitochondrial cytochrome c at each end of the chain. The N-terminal glycine is not acetylated and corresponds to position 1 of mammalian cytochrome c when the cysteine residues of the two proteins are aligned.

THE PRIMARY STRUCTURE OF THE CYTOCHROME c FROM VARIOUS ORGANS OF THE HOG

1965 ◽  
Vol 43 (7) ◽  
pp. 1187-1206 ◽  
Author(s):  
J. W. Stewart ◽  
E. Margoliash
Keyword(s):  
Cytochrome C ◽  
Polypeptide Chain ◽  
The Body ◽  
Horse Heart Cytochrome ◽  
Functional Activities ◽  
Amino Terminal ◽  
Single Polypeptide Chain ◽  
Molecular Variants ◽  
Single Polypeptide ◽  
Horse Heart Cytochrome C

The amino acid sequence of hog heart cytochrome c was determined. Like the horse and human heart proteins it was found to consist of a single polypeptide chain 104 residues long with a N-acetylated amino-terminal residue. It differs from horse heart cytochrome c in only three positions, carrying serine instead of threonine at residue 47, glycine instead of lysine at residue 60, and glycine instead of threonine at residue 89. Methods are described for the preparation of cytochrome c, in good yield, from hog liver, kidney, brain, and skeletal muscle. These proteins were all shown to have primary structures identical with that of hog heart cytochrome c, indicating that, notwithstanding differences in the functional activities and embryological origins of the various tissues examined, there is no corresponding change in the structure of cytochrome c. It thus appears likely that the synthesis of all, or at least the bulk, of the cytochrome c is controlled by a single structural gene throughout the body. Minor molecular variants of the protein, which could have been detected at concentrations of 2 to 3% of the entire preparations, were not observed.

scholarly journals The H+/e− stoicheiometry of respiration-linked proton translocation in the cytochrome system of mitochondria

1980 ◽  
Vol 192 (1) ◽  
pp. 203-218 ◽  
Author(s):  
Sergio Papa ◽  
Ferruccio Guerrieri ◽  
Michele Lorusso ◽  
Gianfranco Izzo ◽  
Domenico Boffoli ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Aqueous Phase ◽  
Electron Flow ◽  
Proton Translocation ◽  
O2 Consumption ◽  
Proton Release ◽  
Succinate Oxidation ◽  
Neutral Ph ◽  
Ferricytochrome C ◽  
The Matrix

1. The →H+/e− quotients for proton release from mitochondria associated with electron flow from succinate and duroquinol to O2, ferricyanide or ferricytochrome c, and from NNN′N′-tetramethyl-p-phenylenediamine+ascorbate to O2, were determined from rate measurements of electron flow and proton translocation. 2. Care was taken to avoid, or to take into account, unrelated electron flow and proton translocation, which might take place in addition to the oxido-reductions that were the subject of our analysis. Spectrophotometric techniques were chosen to provide accurate measurement of the rate of consumption of oxidants and reductants. The rate of proton translocation was measured with fast pH meters with a precision of 10−3 pH unit. 3. The →H+/O quotient for succinate or duroquinol oxidation was, at neutral pH, 4, when computed on the basis of spectrophotometric determinations of the rate of O2 consumption or duroquinol oxidation. Higher →H+/O quotients for succinate oxidation, obtained from polarographic measurements of O2 consumption, resulted from underestimation of the respiratory rate. 4. The →H+/2e− quotient for electron flow from succinate and duroquinol to ferricyanide or ferricytochrome c ranged from 3.9 to 3.6. 5. Respiration elicited by NNN′N′-tetramethyl-p-phenylenediamine+ascorbate by antimycin-inhibited mitochondria resulted in extra proton release in addition to that produced for oxidation of ascorbate to dehydroascorbate. Accurate spectrophotometric measurement of respiration showed that the →H+/e− ratio was only 0.25 and not 0.7–1.0 as obtained with the inadequate polarographic assay of respiration. Proton release was practically suppressed when mitochondria were preincubated aerobically in the absence of antimycin. Furthermore, the rate of scalar proton consumption for water production was lower than that expected from the stoicheiometry. Thus the extra proton release observed during respiration elicited by NNN′N′-tetramethyl-p-phenylenediamine+ascorbate is caused by oxidation of endogenous hydrogenated reductants. 6. It is concluded that (i) the →H+/O quotient for the cytochrome system is, at neutral pH, 4 and not 6 or 8 as reported by others; (ii) all the four protons are released during electron flow from quinol to cytochrome c; (iii) the oxidase transfers electrons from cytochrome c to protons from the matrix aqueous phase and does not pump protons from the matrix to the outer aqueous phase.

scholarly journals The amino acid sequence of cytochrome c from Helix aspersa Müller (garden snail)

1972 ◽  
Vol 128 (4) ◽  
pp. 971-974 ◽  
Author(s):  
R. H. Brown ◽  
M. Richardson ◽  
D. Boulter ◽  
J. A. M. Ramshaw ◽  
R. P. S. Jefferies
Keyword(s):  
Amino Acid ◽  
Cytochrome C ◽  
Amino Acid Sequence ◽  
Amino Acid Sequences ◽  
Blocking Group ◽  
Single Polypeptide Chain ◽  
Cytochromes C ◽  
Lending Library ◽  
Single Polypeptide ◽  
Mitochondrial Cytochromes

The amino acid sequence of a snail cytochrome c has been determined. The molecule consists of a single polypeptide chain of 104 residues, and is homologous with other mitochondrial cytochromes c. Unlike the cytochromes c from vertebrates, there is no acetyl blocking group at the N-terminus. A change in an otherwise invariant position has been observed in position 87. Comparison with amino acid sequences of cytochromes c from other sources indicates that the point of divergence of the molluscs and the vertebrates in evolutionary time was 720 million years ago. Experimental details are given in a supplementary paper that has been deposited as Supplementary Publication SUP 50009 at the National Lending Library for Science and Technology, Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1972), 126, 5.

scholarly journals The primary structure of cytochrome c from the rust fungus Ustilago sphaerogena

1972 ◽  
Vol 129 (3) ◽  
pp. 561-569 ◽  
Author(s):  
K. G. Bitar ◽  
S. N. Vinogradov ◽  
C. Nolan ◽  
L. J. Weiss ◽  
E. Margoliash
Keyword(s):  
Amino Acid ◽  
Cytochrome C ◽  
Primary Structure ◽  
Polypeptide Chain ◽  
Rust Fungus ◽  
Single Polypeptide Chain ◽  
C Terminus ◽  
Cytochromes C ◽  
Single Polypeptide ◽  
Asparagine Residue

1. The complete amino acid sequence of cytochrome c from the basidiomycete Ustilago sphaerogena was determined from the amino acid compositions and sequences of either tryptic or chymotryptic peptides, and in homology with at least thirty other established sequences of cytochrome c. 2. The primary structure of the molecule bears all of the characteristics of a mammalian-type cytochrome c, showing the typical clustered distribution of hydrophobic and basic residues with a single polypeptide chain of 107 residues. 3. Like all other fungal cytochromes c, it possesses a free N-terminus, and one less residue at the C-terminus than vertebrate cytochromes c. The region of residues 70–80 is strictly conserved, as is histidine at position 18. Position 26 is occupied by an asparagine residue, in contrast to histidine which occurs at this location in most of the known sequences of mammalian-type cytochromes c. 4. In contrast to some other fungal and plant cytochromes c of known primary structures, the Ustilago cytochrome c molecule does not contain trimethyl-lysine. 5. The sequence of Ustilago cytochrome c differs from the sequences of human, horse, chicken, tuna, wheat, and baker's yeast proteins at loci 47, 43, 44, 44 and 38 respectively.

Purification and Partial Characterization of the Soluble NADH Dehydrogenase from the Phototrophic Bacterium Rhodopseudomonas capsulata

1984 ◽  
Vol 39 (1-2) ◽  
pp. 68-72 ◽  
Author(s):  
Toshihisa Ohshima ◽  
Matsumi Ohshima ◽  
Gerhart Drews
Keyword(s):  
Cytochrome C ◽  
Nadh Dehydrogenase ◽  
Rhodopseudomonas Capsulata ◽  
Subunit Structure ◽  
Ph Optimum ◽  
Single Polypeptide Chain ◽  
Membrane Bound ◽  
Single Polypeptide ◽  
Sepharose 4B

Abstract Soluble NADH dehydrogenase was purified to homogeneity from chemotrophically grown cells of Rhodopseudomonas capsulata by ammonium sulfate fractionation, AH -Sepharose 4B chromatography and FMN-Sepharose 6B affinity chromatography. The enzyme contains a single polypeptide chain of an apparent M, of 37000, suggesting that the subunit structure is different from that of the membrane-bound enzyme. The purified soluble NADH dehydrogenase requires flavin compounds, e.g., FMN, FAD and riboflavin, for activity. Addition of FMN and FAD. but not riboflavin, to the enzyme solution stabilized the enzyme. The pH optimum for activity was at 7.5. The enzyme was specific for NADH as an electron donor while NADPH was inert. Menadione, ferricyanide, cytochrome c and DCIP served as an electron acceptor. The M ichaelis constants for NADH. DCIP, FM N. and cytochrome c were 45, 2.9. 7.9 and 15 μM, respectively. Many properties of soluble NADH dehydrogenase were substantially different from those of the membrane-bound enzyme, suggesting different functions.

scholarly journals Purification and Characterization of a Carbonyl Reductase from Human Liver, which is Competent in the Reduction of 6-Pyruvoyl-Tetrahydropterin

Pteridines ◽  
1989 ◽  
Vol 1 (4) ◽  
pp. 189-198 ◽  
Author(s):  
Petra Steinerstauch ◽  
Yoshitomo Sawada ◽  
Walter Leimbacher ◽  
Sandro Ghisla ◽  
Hans-Christoph Curtius
Keyword(s):  
Human Liver ◽  
Specific Activity ◽  
Polyclonal Antibodies ◽  
Potassium Phosphate ◽  
Side Chain ◽  
Purification And Characterization ◽  
Single Polypeptide Chain ◽  
Apparent Homogeneity ◽  
Single Polypeptide

Summary An enzyme which reduces 6-pyruvoyl-tetrahydropterin has been purified to apparent homogeneity from human liver. It consists of a single polypeptide chain with a molecular weight of 35 kDa, has an isoelectric point of 5.9 ± 0.1 and contains no glycosyl residues. The pure enzyme has a specific activity of 450 mU/mg protein at pH 7.0 in 10 mM potassium phosphate buffer. It converts 6-pyruvoyl-tetrahydropterin to 6-lactoyltetrahydropterin by transfer of the pro 4R-hydrogen of NADPH to form the side chain -OH at position C(2') of the substrate. Km values are 1.8 J..lM for 6-pyruvoyl-tetrahydropterin and 5.5 J..lM for NADPH. Polyclonal antibodies raised against the purified enzyme recognize 6-pyruvoyl-tetrahydropterin reductase in Western blot and ELISA but do not cross-react with human sepiapterin reductase. The enzyme appears to be identical with aldose reductase.

scholarly journals The amino acid sequence of cytochrome c from the locust, Schistocerca gregaria Forskal

1977 ◽  
Vol 163 (2) ◽  
pp. 333-338 ◽  
Author(s):  
A Lyddiatt ◽  
D Boulter
Keyword(s):  
Amino Acid ◽  
Cytochrome C ◽  
Amino Acid Sequence ◽  
Schistocerca Gregaria ◽  
British Library ◽  
Single Polypeptide Chain ◽  
Cytochromes C ◽  
Single Polypeptide ◽  
Taxonomic Groups ◽  
Mitochondrial Cytochromes

The amino acid sequence of locust cytochrome c was determined, although the overlap between chymotryptic and tryptic peptides at residues tyrosine-97 and leucine-98 was not observed, owing to an anomalous tryptic break duplicating the chymotryptic digestion. The molecule consists of a single polypeptide chain of 107 residues, homologous with other mitochondrial cytochromes c. In common with other known insect cytochromes c, it possesses a non-acetylated, four-residue tail at the N-terminus relative to glycine-1 of the standard alignment. A molecular phylogeny for 17 species was constructed relating the cytochrome c molecules of Schistocerca gregaria and other invertebrates with those of representative taxonomic groups. Experimental details are given in a supplementary paper deposited as Supplementary Publication SUP 50077 (24 pages) at the British Library Lending Division, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can obtained on the terms indicated in Biochem. J. (1977) 161, 1.

scholarly journals The reduction of carboxymethyl-cytochrome c by chromous ions

1974 ◽  
Vol 141 (2) ◽  
pp. 455-461 ◽  
Author(s):  
Thomas Brittain ◽  
Michael T. Wilson ◽  
Colin Greenwood
Keyword(s):  
Cytochrome C ◽  
Difference Spectrum ◽  
Order Rate Constant ◽  
Stopped Flow ◽  
Methionine Residue ◽  
Ferricytochrome C ◽  
A Charge ◽  
Kinetics Of ◽  
Dependent Processes ◽  
Kinetics Of Reduction

The reduction of ferricytochrome c and ferricytochrome c carboxymethylated at the haem-linked methionine (residue 80) by Cr2+ ions was studied by stopped-flow techniques. At pH6.2 the kinetics of reduction of ferricytochrome c are simple and correspond to a second-order rate constant of 1.21×103m-1·s-1. Under identical conditions the kinetics of reduction of the carboxymethyl derivative, carboxymethyl-cytochrome c, are complex; two Cr2+-concentration-dependent processes (1.5×104m-1·s-1 and 1.3×103m-1·s-1) lead to the formation of an intermediate which decays in monomolecular fashion (0.15s-1) to form the normal fully reduced material. The kinetic difference spectrum for the overall process corresponds to that found statically, whereas the kinetic difference spectrum of the intermediate minus the oxidized form resembles that of the low-spin ferrous form of carboxymethyl-cytochrome c minus oxidized carboxymethyl-cytochrome c. A model is proposed in which the reduction of low-spin ferric carboxymethyl-cytochrome c to high-spin ferrous carboxymethyl-cytochrome c involves a low-spin ferrous intermediate. The monomolecular step involving the decay of this low-spin ferrous intermediate is associated with an activation energy of approx. 126kJ·mol-1 and is thought to involve both a change of spin state and a protein-conformational event. Although carboxymethyl-cytochrome c represents a mixture of species separable on a charge basis, the above observations were independent of which species was chosen for study.

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