The inhibition of oxygen consumption was studied in vitro using the metabolic inhibitors antimycin A, oligomycin, and sodium cyanide. Primary concern was to determine the rate and extent of oxidative inhibition upon intact rat bone marrow cells. At concentrations of 5 x 1()~ sodium cyanide, or higher, inhibition was total and immediate. At a concentration of 5 x 10~ it was found that sodium cya...

A clear association between seasonal outbreaks of a paralytic disease called konzo and toxic effects from consumption of insufficiently processed bitter cassava roots has been demonstrated in Bandundu region, Zaire. A community-based survey of 6764 inhabitants identified 110 live and 24 dead konzo-affected persons with a history of isolated non-progressive spastic paraparesis of abrupt onset. T...

The rates of oxidation of cyanide with Fe(VI) were measured as a function of pH (8.0-12) and temperature (1530 °C). The reaction was found to be first order for each reactant. The rates decrease with increasing pH. The energy of activation was found to be 38.9 ( 1.0 kJ mol-1 at pH 9.0. The removal of cyanide by oxidation with Fe(VI) was studied at pH 7.5, 9.0, and 12.0. Fe(VI) removal efficienc...

Cyanide is a valuable tool for studying respiratory mechanisms and their rôle in embryonic development: it is relatively specific in its action, penetrates cell membranes readily, is active in low concentration, and may be controlled quantitatively (page 217). Echinarachnius is extremely sensitive to cyanide and the oxygen consumption of both eggs and of sperm is almost completely inhibited by ...

Aspergillus fumigatus possesses a branched mitochondrial electron transport chain, with both cyanide-sensitive and -insensitive oxygen-consumption activities. Mitochondrial reactive oxygen species mediate signaling for alternative oxidase (AOX) expression. A 1173 bp-long Afaox gene encoding a 40 kDa protein has been cloned and identified. Recombinant constructs containing the Afaox ORF were tra...

Biological formation and consumption of molecular hydrogen (H2) are catalyzed by hydrogenases, of which three phylogenetically unrelated types are known: [NiFe]-hydrogenases, [FeFe]-hydrogenases, and [Fe]-hydrogenase. We present a crystal structure of [Fe]-hydrogenase at 1.75 angstrom resolution, showing a mononuclear iron coordinated by the sulfur of cysteine 176, two carbon monoxide (CO) mole...

A survey of neurological abnormalities in two Nigerian villages preselected for their differing consumption of cassava has shown that a degenerative neuropathy occurs with relatively high frequency in the village (Ososa) where cassava consumption was high.It is suggested that eating cassava results in exposure to cyanide, as shown by a raised plasma thiocyanate level, and that the latter, toget...