The effect of cyanide and ferricyanide on the activity of the dissimilatory nitrate reductase of Escherichia coli.
Year: 1982
Type: article
Abstract: A method is described for the large scale purification of the dissimilatory nitrate reductase (EC 1.7.99.4) of Escherichia coli, a procedure which routinely yields over 330 mg of the purified enzyme.The enzyme was released from the membranes by prolonged heat treatment and purified to homogeneity with a yield of 45% and a final specific activity of 80 pmol of nitrite produced/min/mg of protein.It contained 0.80 g atom of molybdenum, and approximately 16 g atoms of iron and 14 g atoms of acid-labile sulfide/200,000 g of protein.Nitrate reductase was sensitive to inactivation by cyanide in three different oxidation-reduction states, Le. dithionite-reduced, ferricyanide-oxidized, and the "as prepared" enzyme.The reduced enzyme was more sensitive to cyanide at pH 7.2 than at pH 10.5, and the rate of inactivation was first order at both pH values.Kinetic analysis revealed that at pH 10.5 reversible enzyme-cyanide complexes were formed with the reduced enzyme (KI = 4.4 x lo-' M).This was not evident
Source: Journal of Biological Chemistry
Authors: M.W. Adams, L.E. Mortenson
Institutions: Purdue University West Lafayette, ExxonMobil (United States)
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,430
OpenAlex ID: W1528199736