scholarly journals CYANIDE-SENSITIVE BACTERIAL RESPIRATORY SYSTEMS DIFFERENT FROM THE USUAL CYTOCHROME-CYTOCHROME OXIDASE SYSTEM

1942 ◽  
Vol 26 (1) ◽  
pp. 1-9 ◽  
Author(s):  
M. G. Sevag ◽  
M. Shelburne
Keyword(s):  
Cytochrome C ◽  
Oxygen Uptake ◽  
Cytochrome Oxidase ◽  
Streptococcus Pyogenes ◽  
Yeast Cells ◽  
Oxidase System ◽  
E Coli ◽  
Respiratory Systems ◽  
Pneumococcus Type

Aerobic respiration of Streptococcus pyogenes and pneumococcus Type 1 are strongly inhibited by KCN, NaN3, and Na2S. The anaerobic glycolysis of glucose by pneumococcus is also inhibited by KCN and NaN3. Streptococcus pyogenes, E. coli, pneumococcus Type 1, B. subtilis, B. proteus, and Staphylococcus aureus did not catalyze the oxygen uptake by p-phenylenediamine in the presence of added cytochrome c or in its absence. Yeast cells, B. subtilis, and B. pyocyaneus oxidized p-phenylenediamine to a dark purple meriquinoid substance in contrast to the other bacteria mentioned above. Streptococcus pyogenes in contrast to pneumococcus Type 1 catalyzed the oxygen uptake by cysteine. Neither of these bacteria catalyzed the oxygen uptake by tyrosine, adrenaline, pyrocatechin, xanthine, and hypoxanthine. Streptococcus pyogenes, pneumococcus Type 1, and E. coli, boiled and not boiled, gave positive peroxidative tests with benzidine showing the presence of hematin compounds. The results discussed in the light of the interpretations offered by Keilin and Harpley show that Streptococcus pyogenes and pneumococcus Type 1 contain cyanide-sensitive respiratory systems which are different from the cytochrome c-cytochrome oxidase system.

Reflectance Spectra and Some Respiratory Reactions of Bovine, Equine and Human Thrombocytes

1957 ◽  
Vol 188 (2) ◽  
pp. 415-419 ◽  
Author(s):  
Charles R. Goucher ◽  
W. Kocholaty
Keyword(s):  
Cytochrome C ◽  
Redox Potential ◽  
Cytochrome Oxidase ◽  
Sodium Azide ◽  
Visible Region ◽  
Reflectance Spectra ◽  
Absorption Bands ◽  
Oxidase System ◽  
Chromatic Properties

Reflectance spectra of human, bovine and equine thrombocytes reveal the existence of pigments which absorb in the visible region of the spectrum. The chromatic properties of these pigments change with the redox potential of the cell. These spectra alterations suggest the existence of a cytochrome system, but the position of the absorption bands does not permit their identification with known mammalian cytochromes. However, platelet homogenates contain a cytochrome oxidase which oxidizes mammalian cytochrome c and which is inhibited by sodium azide. Platelet extracts also contain a DPNH oxidase system which is inhibited by sodium azide.

scholarly journals Functional Flexibility of the FimH Adhesin: Insights from a Random Mutant Library

2000 ◽  
Vol 68 (5) ◽  
pp. 2638-2646 ◽  
Author(s):  
Mark A. Schembri ◽  
Evgeni V. Sokurenko ◽  
Per Klemm
Keyword(s):  
Amino Acid ◽  
Conformational Changes ◽  
Binding Capacity ◽  
Random Mutagenesis ◽  
Yeast Cells ◽  
Carbohydrate Binding ◽  
Functional Changes ◽  
E Coli ◽  
Type 1 Fimbriae

ABSTRACT Type 1 fimbriae are surface organelles of Escherichia coli which mediate d-mannose-sensitive binding to different host surfaces. This binding is conferred by the minor fimbrial component FimH. Naturally occurring variants of the FimH protein have been selected in nature for their ability to recognize specific receptor targets. In particular, variants that bind strongly to terminally exposed monomannose residues have been associated with a pathogenicity-adaptive phenotype that enhances E. colicolonization of extraintestinal locations such as the urinary bladder. In this study we have used random mutagenesis to specifically identify nonselective mutations in the FimH adhesin which modify its binding phenotype. Isogenic E. coli clones expressing FimH variants were tested for their ability to bind yeast cells and model glycoproteins that contain oligosaccharide moieties rich in either terminal monomannose, oligomannose, or nonmannose residues. Both the monomannose- and the oligomannose-binding capacity of type 1 fimbriae could be altered by minor amino acid changes in the FimH protein. The monomannose-binding phenotype was particularly sensitive to changes, with extensive differences in binding being observed in comparison to wild-type FimH levels. Different structural alterations were able to cause similar functional changes in FimH, suggesting a high degree of flexibility to target recognition by this adhesin. Alteration of residue P49 of the mature FimH protein, which occurs within the recently elucidated carbohydrate-binding pocket of FimH, completely abolished its function. Amino acid changes that increased the binding capacity of FimH were located outside receptor-interacting residues, indicating that functional changes relevant to pathogenicity are likely to be due to conformational changes of the adhesin.

scholarly journals INFLUENCE OF SULFHYDRYL REAGENTS ON THE CYTOCHROME c-CYTOCHROME OXIDASE SYSTEM

1950 ◽  
Vol 185 (2) ◽  
pp. 469-477
Author(s):  
Cornelius W. Kreke ◽  
Sister M. Albertus Schaefer ◽  
Sister M. Angelice Seibert ◽  
Elton S. Cook
Keyword(s):  
Cytochrome C ◽  
Cytochrome Oxidase ◽  
Sulfhydryl Reagents ◽  
Oxidase System

scholarly journals The mitochondrial oxidation of quinol monophosphates

1970 ◽  
Vol 118 (5) ◽  
pp. 719-731
Author(s):  
J. M. Young
Keyword(s):  
Electron Transport ◽  
Cytochrome C ◽  
Oxygen Uptake ◽  
Cytochrome Oxidase ◽  
Rat Liver ◽  
Mode Of Action ◽  
Electron Transport Chain ◽  
Rapid Reduction ◽  
Transport Chain ◽  
Mitochondrial Oxidation

1. Mitochondria from ox heart and rat liver catalysed a slow cyanide-sensitive oxidation of 2,3-dimethylnaphthaquinol monophosphate, duroquinol monophosphate, menadiol 1-phosphate and menadiol 4-phosphate. 2. The release of Pi was concomitant with oxygen uptake. 3. The oxidation was somewhat stimulated by Ca2+ and Pi, and weakly inhibited by 2,4-dinitrophenol. 4. The quinol monophosphates effected a rapid reduction of free cytochrome c, and consequently addition of cytochrome c greatly increased the rate of the mitochondrial oxidation of 2,3-dimethylnaphthaquinol monophosphate. 5. This quinol phosphate interacts with the electron-transport chain at the level of cytochrome c. 6. Polylysine promoted an interaction between 2,3-dimethylnaphthaquinol monophosphate and cytochrome oxidase. Thus, although polylysine blocks mitochondrial oxidations via reduced cytochrome c, the oxidation of the quinol phosphate was strongly stimulated. 7. This stimulation was most effective in the most intact mitochondrial preparations and was inhibited by ADP and by Pi. 8. The implications of these results for factors limiting the rate of quinol phosphate oxidation, the mode of action of stimulators and the mechanism of Pi formation are discussed.

scholarly journals The Estimation of Cytochrome C Oxidase in Animal Tissues

1948 ◽  
Vol 1 (1) ◽  
pp. 139 ◽  
Author(s):  
TAF Quinlan-Watson ◽  
DW Dewey
Keyword(s):  
Absorption Spectrum ◽  
Cytochrome C ◽  
Oxygen Uptake ◽  
Cytochrome Oxidase ◽  
Cytochrome C Oxidase ◽  
Rate Of Change ◽  
Animal Tissues ◽  
Large Excess ◽  
Spectrophotometric Measurement

Method for the stimation of cytochrom, c oxidase are dependent eitherupon the change which occurs in the absorption spectrum of cytochrome c whenit is oxidized by cytochrome oxidase (Altschul, Abrams, and Hogness 1939;Albaum, Tepperman and Bodansky 1946a, 1946b), or upon the absorption ofgaseous oxyen by, a !!ysten. which consists essentially of a preparation of cytochromeoX~,�Jase in the. pz:esence of a large excess of reduced cytochrome c. Ineither case, it is the rate of oxidation of reduced cytochrome c which is es~imated;in the former by spectrophotometric measurement of the rate of change in lighttransmission . at two different wllyelengths; and, in the latter by manometricestimation of the rate of oxygen uptake (Keilin and Hartree 1938; Stotz 1939;Schneider and Potter 1943). The rate of oxidation of the reduced cytochrome c . , ,"is proportional, under. certain, conditions, to the amount of cytochrome oxidasepresent, apd so. can be used as a measure of ~he activity' of cytochrome oxidase .itself.

scholarly journals Cytochrome oxidase assembly does not require catalytically active cytochrome c.

2003 ◽  
Vol 278 (43) ◽  
pp. 42728
Author(s):  
Antoni Barrientos ◽  
Danielle Pierre ◽  
Johnson Lee ◽  
Alexander Tzagoloff
Keyword(s):  
Cytochrome C ◽  
Cytochrome Oxidase ◽  
Catalytically Active

scholarly journals The Oxidation of o-Aminophenols by Cytochrome c and Cytochrome Oxidase

1959 ◽  
Vol 234 (6) ◽  
pp. 1600-1604 ◽  
Author(s):  
H.T. Nagasawa ◽  
H.R. Gutmann ◽  
M.A. Morgan
Keyword(s):  
Cytochrome C ◽  
Cytochrome Oxidase

Pulmonary Gas Exchange and Oxygen Uptake During Exercise in Patients with Type 1 Diabetes Mellitus

1992 ◽  
Vol 9 (3) ◽  
pp. 252-257 ◽  
Author(s):  
Th. Wanke ◽  
D. Formanek ◽  
M. Auinger ◽  
H. Zwick ◽  
K. Irsigler
Keyword(s):  
Diabetes Mellitus ◽  
Type 1 Diabetes ◽  
Gas Exchange ◽  
Oxygen Uptake ◽  
Type 1 Diabetes Mellitus ◽  
Pulmonary Gas Exchange

scholarly journals MITOCHONDRIAL BIOGENESIS DURING DIFFERENTIATION OF ARTEMIA SALINA CYSTS

1973 ◽  
Vol 58 (3) ◽  
pp. 643-649 ◽  
Author(s):  
H. Schmitt ◽  
H. Grossfeld ◽  
U. Z. Littauer
Keyword(s):  
Cytochrome C ◽  
Cytochrome Oxidase ◽  
Cytochrome B ◽  
Mitochondrial Biogenesis ◽  
Brine Shrimp ◽  
Morphological Changes ◽  
Artemia Salina ◽  
Mitochondrial Morphology ◽  
Second Stage ◽  
Two Stages

Mitochondria isolated from cysts of Artemia salina (brine shrimp) were found to be devoid of cristae and to possess a low respiratory capability. Hydration of the cysts induces marked biochemical and morphological changes in the mitochondria. Their biogenesis proceeds in two stages. The first stage is completed within 1 h and is characterized by a rapid increase in the respiratory capability of the mitochondria, their cytochrome oxidase, cytochrome b, cytochrome c and perhaps some morphological changes. In the second stage there is an increase in the protein-synthesizing capacity of the mitochondria as well as striking changes in mitochondrial morphology leading to the formation of cristae.

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