Little in general is known about how heme proteins are assembled from their constituents in cells. The Gram-positive bacterium Enterococcus faecalis cannot synthesize heme and does not depend on it for growth. However, when supplied with heme in the growth medium the cells can synthesize two heme proteins; catalase (KatA) and cytochrome bd (CydAB). To identify novel factors important for catala...

A gene coding for catalase (hydrogen-peroxide:hydrogen-peroxide oxidoreductase; EC 1.11.1.6) of the gram-positive bacterium Listeria seeligeri was cloned from a plasmid library of EcoRI-digested chromosomal DNA, with Escherichia coli DH5 alpha as a host. The recombinant catalase was expressed in E. coli to an enzymatic activity approximately 50 times that of the combined E. coli catalases. The ...

Betalains are a group of nitrogen-containing pigments that color plants in most families of Caryophyllales. Their biosynthesis has long been proposed to begin with hydroxylation of L-tyrosine to L-DOPA through monophenolase activity of tyrosinase, but biochemical evidence in vivo remains lacking. Here we report that a Group 4 catalase, catalase-phenol oxidase (named as AcCATPO), was identified,...

Hepatic catalase activity in unanesthetized man has been de termined by measuring the disappearance rate of hydrogen perox ide spectrophotometrically in homogenates from needle biopsy specimens of liver. Ten healthy male prisoners, 59 patients with advanced cancer, and 60 cadavers shortly after death with cancer were studied. There is a wide range of catalase activity in normal human liver. Cat...

Stern (1) has found that as much as 0.13 N ethyl hydrogen peroxide is required to give 50 per cent inhibition of the destruction of hydrogen peroxide by catalase. This is difficult to understand in view of the high affinities of catalase for ethyl hydrogen peroxide in both the primary and secondary compounds (~2 X 10” M) (2), in which all the catalase hematins are bound to ethyl hydrogen peroxi...

The endemic occurrence of favism in certain Mediterranean regions provided an investigative opportunity for testing in vivo the validity of claims as to the role of catalase in protecting human erythrocytes against peroxidative injury. Reduced activity of catalase was found in the erythrocytes of six boys who were deficient in erythrocytic glucose-6-phosphate dehydrogenase (G6PD) and who were s...

Immunoelectrophoretic analysis of 25-day-old newborn and adult rat livers verified the presence of a 6-arc pattern of catalase observed earlier for purified rat hepatic catalase and for liver homogenates. Application of the immunoelectrophoretic method to fetal and newborn liver homogenates revealed a gradual shift from predominantly anodic arcs present in the fetal and early newborn period to ...