Glycine 170 Iron reduction

Ke and Regier [71] have described a direct potentiometric determination of fluoride in seawater after extraction with 8-hydroxyquinoline. This procedure was applied to samples of seawater, fluoridated tap-water, well-water, and effluent from a phosphate reduction plant. Interfering metals, e.g., calcium, magnesium, iron, and aluminium were removed by extraction into a solution of 8-hydroxyquinoline in 2-butoxyethanol-chloroform after addition of glycine-sodium hydroxide buffer solution (pH 10.5 to 10.8). A buffer solution (sodium nitrate-l,2-diamino-cyclohexane-N,N,N. AT-tetra-acetic acid-acetic acid pH 5.5) was then added to adjust the total ionic strength and the fluoride ions were determined by means of a solid membrane fluoride-selective electrode (Orion, model 94-09). Results were in close agreement with and more reproducible than those obtained after distillation [72]. Omission of the extraction led to lower results. Four determinations can be made in one hour. 

Deacylation of deferriferrichrysin occurs in 20 min. in IN HCi at 100°. Trihydrochloride so obtained may be reacylated and, after removal of O-acetyl in methanolic ammonia and re-insertion of iron, ferrichrysin is obtained. The trihydrochloride hexapeptide may be reduced with platinum oxide and H2. Treatment of the latter compound with 2,4-dinitrofluorobenzene followed by hydrolysis gives N8-DNP ornithine. Hydrolysis of ferrichrysin in 57% HI gives serine, glycine, alanine, ornithine and ammonia in the molar ratios 0.24 1.00 1.50 2.91 0.09. Hydrolysis of deferriferrichrysin in 6N HCI, reduction of the hydrolysate with H2 and platinum oxide and addition of excess fluorodinitrobenzene yields crystalline derivatives of glycine, L-serine and L-ornithine. 

The reaction of Mo(H20)63+ and nitrate in aqueous solutions results in the formation of Mo2Oi(H20)62+ and nitrite. Mo(III) coordinated to oxygen and nitrogen donor atoms of EDTA also reduces nitrate in aqueous solutions. The reduction of nitrate by a Mo(III)-EDTA complex results in the formation of nitrite and a Mo(V)-EDTA complex, as determined by chemical and spectrophotometric techniques. These reactions serve as models for biological nitrate reduction. In addition, molybdate coordinates to naturally produced phenolates. The molybdenum-coordinating phenolates also coordinate tungstate and ferric iron. Two of these phenolates contain threonine, glycine, alanine, and 2,3-dihydroxybenzoic acid. 

The presence of fixation of CO by minerals led to acetate, pyruvate, acetaldehyde, glycerol-aldehyde, acetone, methyl mercaptan (also called methanethiol), methyl-thioacetate, glycine, and aspartic acid. Alanine forms by reduction of pyruvate with ammonia. Iron sulfide and hydrogen sulfide reduce molecular nitrogen to ammonia according to the overall reaction ... 

When a P. aeruginosa mutant (PALS 128) was grown under iron rich conditions, the specific activity of the SA-forming enzymes was below the limits of detection [79]. Liu et al. [88], suggest that entC gene expression may be limited at the translational level as well, even when the operon is induced under iron deficiency. This may be understandable because chorismic acid is an essential metabolite for Phe, Trp, Tyr, folate and ubiquinone synthesis. In B. subtilis it was shown that the accumulation of 2,3-DHBA(Glycine) was influenced by the levels of aromatic amino acids and anthranilic acid. Anthranilic acid inhibited the synthesis of DHBA from chorismic acid [117]. It seemed that the reduction in phenolic acid accumulation caused by aromatic amino acids is a consequence of enzyme repression [121]. The synthesis of 2,3-DHBA in B. subtilis is also reduced by other phenolic acids, such as m-substimted benzoic acids. Inhibition of accumulation of phenolic acid by other phenolic acids, would indicate a fairly specific effect on phenolic acid synthesis, but not on the accumulation of coproporphyrin that also accumulates in iron-deficient cultures oiB. subtilis [121]. 

The absorption of ciprofloxacin is markedly reduced by iron and zinc compounds. Several studies have clearly demonstrated reductions in the AUC and maximum serum levels of 30 to 90% with ferrous fumarate, ferrous gluconate, ferrous sulfate, iron-glycine sulfate, Centrum Forte (a multi-mineral preparation containing iron, magnesium, zinc, calcium, copper and manganese) and with Stresstabs 600-with-zinc (a multi vitamin-with-zinc preparation). However iron-ovotransferrin has been found to have no significant effect on the absorption of ciprofloxacin. ... 

Complexing of the reductant also induces rate enhancement of cobalt(ni) complexes. The rate constant for reduction of [Co(NH3)60Ac] + by iron(n) has been given a lower limit of 5 x 10 1 mol s whereas when the reductant is complexed to A-methyliminodiacetate (L ) in glycine buffer the corresponding value is 1.52 x 1()- 1 mol s. The rate law derived is... 

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