Effect of Fungicides and Insecticides on Growth and Enzyme Activity of Four Cyanobacteria

Cyanobacterial populations introduced into crop fields as biofertilizer become non-target organisms for the pesticides and fungicides applied in the field. Effect of four commonly used pesticides viz. Bagalol, Mancozeb (fungicides), Thiodan and Phorate (insecticides) was studied on growth and different enzymes of four cyanobacterial species viz. Nostoc ellipsosporum, Scytonema simplex, Tolypothrix tenuis, and Westiellopsis prolifica. EC 50 concentration of each pesticide was determined for all cyanobacteria. Bagalol and Thiodan were found to be the most toxic. Both the fungicides and insecticides inhibited the activity of nitrogenase and glutamine synthetase (GS) at EC 50 concentration in all the four species studied. Bagalol incurred maximum inhibition of nitrogenase and GS activity on N. ellipsosporum and S. simplex while Thiodan and Phorate had maximum effect on T. tenuis, and W. prolifica. Mancozeb had lesser effect on all the above enzymes. One catabolic enzyme of carbohydrate metabolism, isocitrate dehydrogenase (ICDH) and one anabolic enzyme isocitrate lyase (ICL), which is related to glyoxylate pathway as well as gluconeogenesis, were also assayed. Cell free extracts of cyanobacteria treated with pesticides for 7 days show a drastic reduction of ICDH activity. ICL activity was induced in the organisms when treated with pesticides.     

EFFECTS OF AMPHETAMINE ADMINISTRATION IN VIVO ON IN VITRO PROTEIN SYNTHESIZING SYSTEM FROM RAT BRAIN 1

Abstract— A highly active in vitro protein synthesizing system (S-28) has been prepared from rat brain. Poly (U)-dependent [³H] phenylalanine incorporation by brain S-28 system is significantly inhibited by D-amphetamine. The extent of inhibition by amphetamine is significantly higher than by other biogenic amines such as dopamine and serotonin. At the 100°g level of amphetamine, the inhibition is about 70°. Experiments with ribosomes and soluble enzymes from control and amphetamine-treated systems indicate that the observed inhibition may be due to the effect of the drug on the ribosomes. Kinetic analysis of the reaction mixture in the presence as well as absence of D-amphetamine indicate that this sympathomimetic drug inhibits polysome formation in vitro.     

The preparation of bile acid amides and oxazolines

Amides obtained by the condensation of some bile acid chlorides with 2-amino-2-methyl-l-propanol on cyclization yield bile acid oxazolines. Physical properties of these bile acid derivatives are described. Some of the oxazolines are non-toxic and are inhibitors of 7-dehydroxylaseactivity in fecal anaerobic bacteria and purified enzymes from these bacteria.     

The complete genomic sequence of Streptomyces spectabilis NRRL-2792 and identification of secondary metabolite biosynthetic gene clusters

Journal of Industrial Microbiology & Biotechnology - This is the first report of a fully annotated genomic sequence of Streptomyces spectabilis NRRL-2792, isolated and identified by The Upjohn...     

Morphology and electrostatics play active role in neuronal differentiation processes on flexible conducting substrates

This commentary discusses and summarizes the key highlights of our recently reported work entitled “Neuronal Differentiation of Embryonic Stem Cell Derived Neuronal Progenitors Can Be Regulated by Stretchable Conducting Polymers.” The prospect of controlling the mechanical-rigidity and the surface conductance properties offers a unique combination for tailoring the growth and differentiation of neuronal cells. We emphasize the utility of transparent elastomeric substrates with coatings of electrically conducting polymer to realize the desired substrate-characteristics for cellular development processes. Our study showed that neuronal differentiation from ES cells is highly influenced by the specific substrates on which they are growing. Thus, our results provide a better strategy for regulated neuronal differentiation by using such functional conducting surfaces.