Studies on the mechanism of inhibition of redox enzymes by substituted hydroxamic acids

Diphenol Oxidases, Enzyme-catalysed Browning and Plant Disease Resistance

“…Substituted hydroxamic acids, which inhibit the cyanide-insensitive (alternate electron transfer) pathway (Schonbaum et al, 1971) are powerful inhibitors of catehoIase (Rich et al, 1978;Mayer and Harel, 1979).…”

“…Hydroxamic acids have the formula R-CONHOH and have been reported as inhibitors et al, of catecholase (Rich et al, 1978). They are aggressive metal chelators and were originally thought to inhibit catecholase by this mechanism; however Rich et al (1978) demonstrated that the inhibition is both competitive and reversible.…”

“…They are aggressive metal chelators and were originally thought to inhibit catecholase by this mechanism; however Rich et al (1978) demonstrated that the inhibition is both competitive and reversible. Furthermore, they were found to have inhibitor constants (Ki values) in the nanomolar range (Rich etal., 1978) and are very effective inhibitors of catecholase.…”

“…Furthermore, they were found to have inhibitor constants (Ki values) in the nanomolar range (Rich etal., 1978) and are very effective inhibitors of catecholase. Salicylhydroxamic acid (SHAM) was investigated by Allan and Walker (1988) and found (in contrast to Rich et al, 1978) to inhibit catecholase non-competitively with a Ki0.2-2 1.tM, yet was without effect on the laccases from spruce, Rims vernicifera or fungal laccases. Later work in the authors' laboratory has confirmed this differential inhibition (Ferrar and Walker, 1996).…”

Inhibition of O2 Consumption Resistant to Cyanide and Its Development by N-Propyl Gallate and Salicylhydroxamic Acid

“…Unfortunately, hydroxamic acids are by no means specific inhibitors. Rich et al (12) have documented inhibition of tyrosinase and peroxidase by SHAM; however, both of these enzymes are inhibited by cyanide. Parrish and Leopold (11) have demonstrated that the cyanide-resistant 02 consumption by ground soybean endosperm which is inhibited by SHAM is attributable to lipoxygenase activity.…”