Phenazine methosulfate

ANTTBIOTTCS - BETA-LACTAMS - CARBAPENEMS AND PENEMS] (Vol 3) Thiozolyl blue-phenazine methosulfate... 

The reaction may be followed by measuring the rate of appearance or disappearance of MADH at 340 nm. In some methods a coupled reaction using diaphorase or phenazine methosulfate plus an indicator dye are used. The amount of pyruvate formed can also be measured colorimetrically. With the general avail-... 

The reduction of tetrazolium salts by NADH is greatly accelerated by electron transfer agents (ETAs) such as phenazine methosulfate (PMS 233) or its derivatives.451-454 Other classes of ETAs such as quinones.455,456 ferricinium,457 phenothiazine,458 the viologens,459 acridiniums,460 and phe-nazinium or quinoxalinium salts461 as well as the enzyme diaphorase462 have been used. 

X. Xu, J.Q. Zhao, D.C. Jiang, J.L. Kong, B.H. Liu, and J.Q. Deng, Ti02 sol-gel derived amperomet-ric biosensor for H202 on the electropolymerized phenazine methosulfate modified electrode. Anal. Bioanal. Chem. 374, 1261-1266 (2002). 

Gardner et al. [165] have shown that the redox-cycling agent phenazine methosulfate (PMS), mitochondrial ubiquinol-cytochrome c oxidoreductase, or hypoxia inactivated aco-nitase in mammalian cells. It has been proposed that the inactivation of aconitase is mediated by superoxide produced by prooxidants because the overproduction of mitochondrial MnSOD protected aconitase from inactivation by the prooxidants mentioned above except hyperoxia. Later on, the reaction of superoxide with aconitases began to be considered as one of the most important ways to NTBI generation in vivo. 

Recently a colorimetric method for estimation of erythrocytic G-6-PDH was described (El). This procedure is based upon the interaction of phenazine methosulfate as electron carrier between NADPH2 formed in the reaction and dichloroindophenol, the rate of the reduction of the latter compound being followed at 620 mp. 

Phenazine methosulfate, cofactor regeneration using, 3 673 Phenazocine, 4 359t Phendimetrazine (Bontril), 3 91 Phenethanolamines, 13 14 Phenethyl alcohol, antimicrobial used in cosmetics, 7 831t... 

Abbreviations ATP, adenosine-5 -triphosphate EPR, electron paramagnetic resL nance EXAFS, extended X-ray absorption 6ne structure Hb, hemoglobin Hb, oxidized (met-) hemoglobin NADH, reduced form of nicotinamide-adenosine dinucleotide PMS, phenazine methosulfate (methylsulfate salt of N-methylphenazonium cation) TMPD, N.N.N N -tetramethylphenylene-1,4 diaminium dication SDS-PAOE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis. 

The activity of complex II (succinate dehydrogenase) is measured as the succinate-dependent reduction of decylubiquinone, which is in turn recorded spectro-photometrically through the reduction of dichlorophenol indophenol at 600 nm (e 19,100-M -cm Fig. 3.8.5). In order to ensure a linear rate for the activity, the medium is added with rotenone, ATP, and a high concentration of succinate. As noticed previously for complex I, decylubiquinone is not a perfect acceptor for electrons from the membrane-inserted complex II [70]. Malonate, a competitive inhibitor of the enzyme, is used to inhibit it. Rather than decylubiquinone, phenazine methosulfate can be utilized, which diverts the electrons from the complex before they are conveyed through subunits C and D, therefore allowing measurement of the activity of subunits A and B. 

Superoxide, the product of the reaction of phenazine methosulfate-NADH, is a reactive oxygen species which can cause DNA damage of the type involved in Tables 10.1 and... 

Scavenging Activity of Various Antioxidants at 80 ]iM Each Against Superoxide Anions Generated by the Phenazine Methosulfate-NADH System... 

Phenazine methosulfate is a skin irritant, so it should be handled with care. Avoid contact with skin and do not breathe dust. 

The enzyme system in A. melanogenum that is responsible for the oxidation of D-arafomo-2-hexulosonic acid (48) to 96 has been separated and partially purified.517 It was discovered518-520 that 96 is further oxidized to carbon dioxide and 2-oxopentanedioic acid (a-ketoglutaric acid) (102) when phenazine methosulfate is added to a cell-free enzyme-preparation from A. melanogenum. 

Esti et al. [8] L-Lactate L-Malate Micro-malolactic fermentation in red wine Lactate oxidase/in a nylon membrane with glutaraldehyde or NAD(P)+-dependent l-malate dehydrogenase oxaloacetate decarboxylating/ immobilised in an aminopropyl glass beads reactor Platinum electrode/ +650mV vs. Ag/AgCl Phenazine methosulfate (for malate sensor)... 

MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide PMS, phenazine methosulfate and T ris, tris(hydroxymethyl)aminomethane. 

Glucose oxidase Phenazine methosulfate with nitroblue tetrazolium chloride Black/purple... 

The toxicological implications in the effect of the respiratory poisons on the enzyme systems of mammals are not fully comprehended, even at this stage of knowledge. For instance, Dixon and Webb (44) point out that the respiration of most animal tissues is insensitive to carbon monoxide which, in the blood, competes with oxygen for the reduced hemoproteins whereas cyanide has a broad inhibitory spectrum which includes various oxidative systems at cellular level and, most importantly, the oxidized forms of the hemoproteins, especially methemoglobin. In this latter connection, phenazine methosulfate has recently been found effective as an experimental therapeutic in cyanide poisoning of mice (13). The respiratory poisons have just been reviewed by Hewitt and Nicholas (72). 

Several findings in the above results are not consistent with earlier reports (Yoshikawa et al., 1995 Van Gelder, 1966 Tiesjema et al., 1973 Schroedl and Hartzell, 1977 Babcock et al., 1978 Blair et al., 1986 Steffens et al., 1993). It has been widely accepted that four electron equivalents are sufficient for complete reduction of the fuUy oxidized enzyme as prepared. However, most of the previous titrations were performed in the presence of electron transfer mediators. In the presence of electron transfer mediators, such as phenazine methosulfate (PMS) under anaerobic conditions, the bovine heart enzyme purified with crystallization also showed a four-electron reduction without the initial lag phase as observed in Fig. 9. A catalytic amount of PMS induced a small spectral change corresponding to the initial lag phase. These results suggest that electron transfer mediators in other titration experiments also induce autoreductions to provide the enzyme form that receives four electrons for the complete reduction. 

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