S TUDIES OF THE enzyme content of leukocytes reported in the past’9 have been performed on mixed cell suspensions. Some attempts to estimate the enzyme values for individual cell types have been made2, 3. 8 on the basis of complex calculations after multiple assays of mixed cell suspensions with varied cell differential counts. The technic of separation of leukocytes on glass bead 12 now permit...

The loci on the Escherichia coli genome of mutations affecting the constitutive enzymes glucose-6-phosphate dehydrogenase (zwf) and gluconate-6-phosphate dehydrogenase (gnd), and the inducible enzyme gluconate-6-phosphate dehydrase (edd), were determined by conjugation and transduction experiments, chiefly by three-factor crosses. They are in the same region of the chromosome, and their order i...

Glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides is irreversibly inactivated by the 2,3'-dialdehyde of NADP+ (oNADP+) in the absence of substrate. The inactivation is first order with respect to NADP+ concentration and follows saturation kinetics, indicating that the enzyme initially forms a reversible complex with the inhibitor followed by covalent modification (KI = 1.8 mM). N...

We present a patient with Burkitt's lymphoma who suffered a severe haemolytic crisis after treatment with rasburicase. This case report underlines the high incidence of glucose-6-phosphate dehydrogenase deficiency in some ethnic groups and the importance of a detailed patient and family history before starting treatment, even in case of emergency. Glucose-6-phosphate dehydrogenase is an essenti...

Degradation of oxidized or oxidatively modified proteins is an essential part of the antioxidant defenses of cells. 4-Hydroxy-2-nonenal, a major reactive aldehyde formed by lipid peroxidation, causes many types of cellular damage. It has been reported that 4-hydroxy-2-nonenal-modified proteins are degraded by the ubiquitin-proteasome pathway or, in some cases, by the lysosomal pathway. However,...

The chain oxidation of glyceraldehyde-3-phosphate dehydrogenase.NADH by perhydroxyl radicals and propagated by molecular oxygen was studied by the xanthine-xanthine oxidase system, 60Co gamma-ray, and pulse radiolysis. The chain length, amount of NADH oxidized per HO2 generated, increases with increasing acidity of the medium and reaches a value of 73 at pH 5.0. The rate constant for the oxidat...

Haematologica vol. 85(3):March 2000 4. Mason PJ, Sonati MF, MacDonald D, et al. New glucose-6-phosphate dehydrogenase mutations associated with chronic anemia. Blood 1995; 85:1377-80. 5. Poggi V, Town M, Foulkes NS, Luzzatto L. Identification of a single base change in a new human mutant glucose-6-phosphate dehydrogenase gene by polymerase-chain-reaction amplification of the entire coding regio...

We report the characterization of 6 Leishmania tropica isolates from 2 patients with visceral leishmaniasis who were unresponsive to treatment with sodium stibogluconate. The Leishmania isolates, MHOM/KE/81/NLB-029A, -029XIB, and -029XIC and MHOM/KE/81/NLB-030I, -030B, and -030XXA, all from splenic aspirates, were characterized by cellulose acetate electrophoresis using 11 enzymes: malate dehyd...

Stereospecificities are reported for seven dehydrogenases from Acholeplasma laidlawii, an organism from an evolutionarily distinct branch of life which has not previously been studied from a stereochemical point of view. Three of the activities examined (alcohol dehydrogenase, lactate dehydrogenase, and alanine dehydrogenase) catalyze the transfer of the pro-R (A) hydrogen from NADH. Four other...

The enzymic activity of the mammalian pyruvate dehydrogenase complex is regulated by the phosphorylation of three serine residues (sites 1, 2 and 3) located on the E1 component of the complex. Here we report that the four isoenzymes of protein kinase responsible for the phosphorylation and inactivation of pyruvate dehydrogenase (PDK1, PDK2, PDK3 and PDK4) differ in their abilities to phosphoryl...