Pulsed cytochrome c oxidase from the thermophilic bacterium PS3.
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ABSTRACT:
SUBMITTER: Sone N
PROVIDER: S-EPMC1144366 | biostudies-other | 1984 Nov
REPOSITORIES: biostudies-other
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Project description:Reaction of O2 and CO with a caa3-type terminal cytochrome oxidase (EC 1.9.3.1) from the thermophilic bacterium PS3 grown with high aeration was studied at low temperatures. The CO recombination at the temperature range studied (-50 degrees C to -80 degrees C) followed first-order kinetics with an activation energy of 29.3 kJ/mol (7.0 kcal/mol). In the presence of O2 at -113 degrees C the photolysed reduced form binds O2 to form an 'oxy' intermediate similar to Compound A. At a higher temperature (-97 degrees C) another intermediate, similar to Compound B, is formed as a result of electron transfer from the enzyme to the liganded O2.
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2008-04-15 | GSE11153 | GEO
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2008-04-15 | E-GEOD-11153 | biostudies-arrayexpress