Cytochrome bSh8-d complex, a terminal oxidase in the respiratory chain of Escherichia coli K12 grown under the condition of limited oxygen, was purified to near homogeneity. The purified oxidase complex is composed of equimolar amounts of two polypeptides, with M, = 26,000 and 51,000, determined with gel eIectrophoresis in the presence of sodium dodecyl sulfate. It contains 12.3 nmol of protohe...

A single catalytic site model is proposed to account for the multiphasic kinetics of oxidation of ferrocytochrome c by cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1). This model involves nonproductive binding of substrate to sites near the catalytic site on cytochrome c oxidase for cytochrome c, decreasing the binding constant for cytochrome c at the catalytic site. ...

The Cox2 subunit of Saccharomyces cerevisiae cytochrome c oxidase is synthesized in the mitochondrial matrix as a precursor whose leader peptide is rapidly processed by the inner membrane protease following translocation to the intermembrane space. Processing is chaperoned by Cox20, an integral inner membrane protein whose hydrophilic domains are located in the intermembrane space, and Cox20 re...

Cytochrome bSh8-d complex, a terminal oxidase in the respiratory chain of Escherichia coli K12 grown under the condition of limited oxygen, was purified to near homogeneity. The purified oxidase complex is composed of equimolar amounts of two polypeptides, with M, = 26,000 and 51,000, determined with gel eIectrophoresis in the presence of sodium dodecyl sulfate. It contains 12.3 nmol of protohe...

The method used by Potter, Albaum, and others (1, 2) for studying the effects of various inhibitors on cytochrome oxidase has been adapted successfully to the assay of the cytochrome oxidase content of rat tissues. The rate of enzymatic oxidation of reduced cytochrome c is measured. A microadaptation enables the measurement of the cytochrome oxidase content of as little as 4 y (wet weight) of a...

In this study, near-infrared spectroscopy was applied to examine whether cytochrome oxidase in the rat brain is inhibited by nitric oxide in vivo. During normoxia, intravenous N(G)-nitro-L-arginine methyl ester (L-NAME) administration significantly decreased the cerebral saturation of hemoglobin with oxygen but did not alter the cytochrome oxidase redox state. Anoxia significantly reduced the c...

Introduction Superoxide (OLo-) is produced by phagocytic leukocytes in response to a variety of stimuli. The activation of 0,' production by neutrophils following binding by plasma membrane receptors of the phagocyte to opsonized bacteria or to peptides from degraded bacteria is of great importance. The 0,'and its reaction products contribute to the microbicidal activities of these cells, and s...

Pancorius Simon, 1902 is a relatively large genus of jumping spider family Salticidae and currently contains 42 valid species that are mainly distributed in South East Asia, 11 which recorded from China. A new the Guiyang City southwest China, described under name P. guiyang Yang, Gu & Yu, sp. nov. Detailed descriptions photographs provided. DNA barcodes (a partial fragment mitochondrial cy...

Numerous attempts have been made to separate the insoluble cytochromes of mammalian heart muscle. Von Euler and Hellstriim in 1939 (1) used sodium cholate and ammonium sulfate and obtained a preparation containing only cytochrome b. Straub (2) obtained a fraction with sodium cholate and ammonium sulfate in which he demonstrated cytochrome oxidase (called cytochrome a3 by him after Keilin and Ha...

Purified cytochrome c oxidase from bakers’ yeast can be resolved into six polypeptide bands by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The apparent molecular weights of these components are I, 42,000; II, 34,500; III, 23,000; IV, 14,000; V, 12,500; and VI, 9,500. (Although Component V actually consists of two distinct polypeptide species, it will be regarde...