Carbonic anhydrase carbon monoxide

Carbon monoxide oxidase 893 Carbonic acid, pkCa value of 99 Carbonic anhydrase 443,676 - 678,710 active site structure 679 mechanism 678 turnover number of 458,678 Carbonium ion. See Carbocation 1,1 -Carbonyl-diimidazole 105s Carbonyl group... 

Figure 9 Stimulated photon echoes from various test molecules in different enzymes CaN-j (azide bound to carbonic anhydrase), Hb-lSb- (azide bound to hemoglobin), and Hb-CO (carbon monoxide bound to hemoglobin). The signal is plotted against delay time r for selected delay times T together with global fits (solid lines). The oscillatory part in the experimental data, which is not reproduced by these fits, reflects the anharmonicity of the transition and is due to interference between fifth and third order nonlinear polarization term (52). (From Ref. 31.)...

It is evident from these data that the transition frequency fluctuation correlation function of samples that have the same probe molecule (azide) embedded into two different proteins (hemoglobin and carbonic anhydrase), or of the sample with different probe molecules (azide, carbon monoxide) embedded to one protein (hemoglobin), all differ considerably. This, we believe, is a consequence of sensitivity of this spectroscopic technique to the local structure, which is different in each case. This result must be contrasted with electronic dephasing, where it was found that the energy gap fluctuation correlation function reflects the response of the bulk solvent and is essentially independent of the chromophore used as a probe (81). 

Keilin and Mann (1940a) reported that cyanide inhibits the enzyme 85 % in concentrations as low as 4 X 10 M. They found inhibition completely reversible. The inhibition with carbon monoxide, found by Meldrum and Houghton (1933) and Van Goor (1934), was not observed by Kiese and Hastings (1940). Keilin and Manir (1940a) adduce the instantaneous and reversible inhibition brought about by cyanide, sulfide, and azide as important evidence that a metal, in this instance zinc, must be the active group of carbonic anhydrase. 

Cadmium pseudohalides, 981 solid state, 985 Carbamic acid, thio-metal complexes, 978 Carbaplatinaboranes conformation, 374 Carbazide, thio-metal complexes, 978 Carbonic anhydrases zinc, 1001,1004 zinc-carbonyl mechanism, 1003 Carbon monoxide estimation... 

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