Mycobacterium fortuitum and Mycobacterium chelonei are distinguished unambiguously by the combined use of five test characters: nitrate reductase, beta-glucosidase, acid production from fructose, penicillinase, and trehalase. Typically, M. fortuitum was nitrate reductase positive, beta-glucosidase positive; M. chelonei was nitrate reductase negative, beta-glucosidase negative, penicillinase pos...

A study was done to relate the in vivo reduction of nitrate to nitrate uptake, nitrate accumulation, and induction of nitrate reductase activity in intact barley seedlings (Hordeum vulgare L. var. ;Numar'). The characteristics of nitrate uptake in response to both time and ambient concentration of nitrate regulated reduction and accumulation. Uptake, accumulation, and in vivo reduction achieved...

Nitrate induces the formation of nitrate reductase activity in barley (Hordeum vulgare L. cv. Himalaya) aleurone layers. Previous work has demonstrated de novo synthesis of alpha-amylase by gibberellic acid in the same tissue. The increase in nitrate reductase activity is inhibited by cycloheximide and 6-methylpurine, but not by actinomycin D. Nitrate does not induce alpha-amylase synthesis, an...

background anaerobic-inducible promoters are alternatives of chemical-inducible promoters for expression of recombinant proteins especially in conditions where chemical induction is not possible or anaerobic conditions are preferable. the nirb promoter is the promoter of the first gene of nir operon in escherichia coli, which encodes nadh-dependent nitrite reductase. this promoter is naturally ...

The nitrate reductase of Escherichia coli K-12 was localized in a particulate fraction of the cell and it sedimented as if it were bound to a large substructure that is subject to fragmentation during cell disruption procedures. Soluble enzyme, exhibiting a homogenous profile in sucrose gradients, was released from this fraction by an alkaline-heat treatment. Less than 1.5% of total active nitr...

In vitro formation of reduced nicotinamide adenine dinucleotide phosphate (NADPH)-nitrate reductase (NADPH: nitrate oxido-reductase, EC 1.6.6.2) has been attained by using extracts of the nitrate reductase mutant of Neurospora crassa, nit-1, and extracts of either photosynthetically or heterotrophically grown Rhodospirillum rubrum, which contribute the constitutive component. The in vitro forma...

With respect to cofactor requirements, NADH, and FMNH(2) were equally effective as electron donors for nitrate reductase obtained from leaves of maize, marrow, and spinach, when the cofactors were supplied in optimal concentrations. The concentration of FMNH(2) required to obtain half-maximal activity was from 40- to 100-fold higher than for NADH. For maximal activity with the corn enzyme, 0.8 ...

Nitrate reductase activity in excised embryos of Agrostemma githago increases in response to both NO(3) (-) and cytokinins. We asked the question whether cytokinins affected nitrate reductase activity directly or through NO(3) (-), either by amplifying the effect of low endogenous NO(3) (-) levels, or by making NO(3) (-) available for induction from a metabolically inactive compartment. Nitrate...

The enzyme systems which catalyze the reduction of nitrate to nitrite have generally been classified into two broad types: (a) assimilatory nitrate reductase, which is responsible for the first step in the reduction of nitrate for the ultimate biosynthesis of nitrogen-containing cell constituents (e.g., amino acids aind purines and pyrimidines), and (b) respiratory or dissimilatory nitrate redu...

The standard procedure for the in ritro extraction of nitrate reductase from the tip region (0-2 cm) of the primary root of the maize (Zea mays L.) seedling indicated an activity of the enzyme approximately 5-fold higher than that obtained with an in vivo assay. In more mature regions of the primary root the ratio of in vitro to in vivo activity was much lower and in older seedlings was less th...