Isolation of an Asm− mutant of Rhizobium japonicum defective in symbiotic N2-fixation

Abstract A mutant strain of Rhizobium japonicum (CJ9) unable to assimilate ammonium (Asm⁻) was isolated following mutagenesis with N -methyl N -nitro-nitrosoguanidine (NTG). Glutamate synthase activity was not detectable in cell-free extracts of the mutant strain in contrast to the wild type and revertant strains. Although mutant CJ9 induced nitrogenase activity in an 'in vitro' assay system under microaerobic conditions, it failed to fix nitrogen (acetylene reduction) in soybean root nodules. These properties of mutant CJ9 constitute a new Asm⁻ mutant class in Rhizobium spp.     

The effect of hycanthone and maleic hydrazide on the frequency of micronuclei in the bone-marrow erythrocytes of mice.

Male Swiss mice were assigned to 6 groups of either 3 or 4 animals each. 3 groups were given hycanthone methanesulfonate intraperitoneally, at 40, 80 or 120 mg/kg, respectively; the dose was repeated after an interval of about 24 h. At the same time 2 groups received maleic hydrazide at 100 or 200 mg/kg, and the remaining group was given dimethyl sulfoxide which was used as a solvent for both drugs. 6 h after the second injection, the mice were killed and bonemarrow preparations were made. Hycanthone induced a significant increase in the frequency of micronuclei in the polychromatic erythrocytes and suppressed the P/N ratio significantly. However, there was no dose-response relationship. Maleic hydrazide, on the other hand, failed to influence the incidence of micronuclei or the ratio of poly- to normo-chromatic erythrocytes.     

Novel Derivatives of Rhodanine-3-Hippuric Acid as Active Inhibitors of Aldose Reductase: Synthesis,Biological Evaluation,and Molecular Docking Analysis

Russian Journal of Bioorganic Chemistry - Inhibitors of aldose reductase provide a feasible mode of action against diabetic complications. Based on the marketed aldose reductase inhibitor...