A new and simple differential pulse polarographic procedure was established for the trace determination of mercury(II). An indirect method had to be used since no polarographic peak can be observed for its direct determination. According to their standard potentials, the reaction between SO2− 3 and Hg(II) was suitable. The peak height of sulfite at about –0.70 V (pH 6, 7) was sharp, high, and v...

The present structural revision of the title compound, tetra-cadmium tetra-sulfite hexa-hydrate, [Cd(4)(SO(3))(4)(H(2)O)(5)]·H(2)O, is a low-temperature upgrade (T = 100 K and R = 0.017) of the original room-temperature structure reported by Kiers & Vos [Cryst. Struct. Commun. (1978). 7, 399-403; T = 293 K and R = 0.080). The compound is a three-dimensional polymer with four independent cadmium...

Sulfite dehydrogenases (SDHs) catalyze the oxidation and detoxification of sulfite to sulfate, a reaction critical to all forms of life. Sulfite-oxidizing enzymes contain three conserved active site amino acids (Arg-55, His-57, and Tyr-236) that are crucial for catalytic competency. Here we have studied the kinetic and structural effects of two novel and one previously reported substitution (R5...

STUDY OBJECTIVE Exposure to cyanide in fires and industrial exposures and intentional cyanide poisoning by terrorists leading to mass casualties is an ongoing threat. Current treatments for cyanide poisoning must be administered intravenously, and no rapid treatment methods are available for mass casualty cyanide exposures. Cobinamide is a cobalamin (vitamin B(12)) analog with an extraordinaril...

The production of singleand mixed-sugar streams and their conversion to bioproducts were studied using sulfite pulping streams as feedstocks. Sulfite pulp, sludge, and spent sulfite liquor (SSL) were utilized because they are concurrently generated alongside of bleached pulp, and because the pulping process renders pretreatment unnecessary. SSL, comprised of mostly monomeric hexose and pentose ...

Sulfite reductase (EC 1.8.1.2) has been purified lQO-fold from spinach leaves. The enzyme catalyzes the reduction cf sulfite to sulfide, with the use of reduced methyl viologen. NADH and NADPH are not capable of replacing reduced methyl viologen. A stoichiometry of 6 molecules of reduced methyl viologen oxidized per molecule of sulfide formed has been found. The enzyme, following treatment with...

Cell-free extracts from several microorganisms, when prepared by methods originally devised for Chlorella pyrenoidosa (Emerson strain 3) and incubated anaerobically with ATP, Mg(2+), and 2, 3-dimercaptopropan-1-ol, are capable of reducing sulfate-(35)S to thiosulfate. These microorganisms include, in addition to C. pyrenoidosa (Emerson strain 3), several other strains of C. pyrenoidosa, Chlorel...