Kinetic studies on the reaction between native globin and haem derivatives

Abstract

It was reported by Hill & Holden (1926), and confirmed by later workers, that the reaction between haematin and globin is rapid, but no numerical results appear to have been published. The reaction between peroxidase apoprotein and haematin has, however, been examined (Theorell & Maehly, 1950). It was slow, with a half-time of the order of minutes; the results with different preparations showed variations up to seven-fold in the rate.

Characterization of haem disorder by circular dichroism

“…The reaction of globin with free haem is very fast, being complete in milliseconds when measured optically (Gibson & Antonini, 1960). The rates of change of c.d.…”

Mössbauer spectroscopic evidence on the heme binding to the proximal histidine in unfolded carbonmonoxy myoglobin by guanidine hydrochloride

“…They concluded that the heme in MbCO is intact in the protein even under the denatured condition. If the heme is detached from the protein in the unfolded state, it will be possible either to make an intermediately nonspecific binding of heme-CO to globin [12,14,15], and to unfold this intermediate completely to the unfolded state at high GdnHCl concentrations, or to make heme-CO free. The former case results in a three-state process for the denaturation of MbCO.…”

“…Once if the heme is detached from the protein, the situation is complex. Many studies have been done on the kinetics of heme binding to globin since the pioneering work by Gibson and Antonini [12]. A variety of experimental results shows that the association rate constant of heme and apoMb or apohemoglobin (apoHb) is affected by the states of heme in solution i.e., free heme or nonspecific heme binding to protein (coordination to surface lysines and histidines), monomeric heme or aggregates of heme [12][13][14][15][16][17][18][19][20][21].…”

Biological Implications of Heme Metabolism

“…As such, heme plays a crucial role in fundamentally important physiological, pharmacological and toxicological reactions. In vitro native hemoglobin can be perfectly renatured from heme and apoglobin, at a rapid rate constant of 5 × 10 4 M −1 sec −1 [1]. Then why is heme degraded to iron, biliverdin IXα and carbon monoxide (CO) in vivo?…”