Electron-paramagnetic-resonance studies on cobalt(II) carbonic anhydrase. Low-spin cyanide complexes
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Great Britain Electron - Paramagnetic - Resonance Studies on Cobalt ( ll ) Carbonic Anhydrase LOW - SPIN CYANIDE COMPLEXES By STEPHEN
The low-spin cyanide complexes of three Co(ll) carbonic anhydrases were investigated by electron paramagnetic resonance (e.p.r.) at 9 and 35GHz. Well-defined and closely axial spectra were obtained only in the absence of oxygen. Several mole equivalents of cyanidewererequired for complete formation ofthecomplexes in frozen solution, although large excesses caused abstraction of the cobalt. Expe...
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Sulphonamide adducts of three Co(II) carbonic anhydrases were investigated by e.p.r. (electron paramagnetic resonance) at helium temperatures. The highly anisotropic9GHz spectra exhibited only three distinct features, with g values between 6.3 and 1.5. Such spectra arise from an electronic state with effective spin S' = i, indicating that the highspin (S= 2) ground level is split into two spin ...
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ژورنال
عنوان ژورنال: Biochemical Journal
سال: 1974
ISSN: 0264-6021
DOI: 10.1042/bj1370587