From Erlenmeyer flask to microplates – lessons learned from measuring Escherichia coli growth

Growth curve measurements are fundamental operations in microbiology and molecular biology. Microplate readers have the advantage of high-throughput and automation. This allows for real-time monitoring of many bacterial cultures and a decrease in labor and costs. The volume and geometry of a well from a microplate imply that calibration and comparative studies must be performed before switching from one cultivation and growth monitoring system to another. Here, Escherichia coli XL1 Blue was used as a reference strain in order to test the feasibility of using a common, filter-based microplate reader for recording growth curves when performing antibiotic and toxicity testing.&nbsp

IN VITRO STABILITY AND ANTIOXIDANT POTENTIAL OF THE NEUPROTECTIVE METABOLITE 6-HYDROXY-NICOTINE

Alzheimer’s disease is complex, and it is unlikely that any one single drug or intervention can successfully treat it. The implication of nicotinic acetylcholine receptors (nAChR) in Alzheimer’s disease pathogenesis has opened a new perspective on finding drugs usable for ameliorating the memory problems associated with AD. By using nAchR modulators, the availability of nAChRs for acetylcholine will be increased and the loss of forebrain cholinergic neurons associated with AD might be overcome. The microbial metabolite 6-hydroxy-D-nicotine has the ability to sustain spatial memory in rats by lowering the levels of oxidative stress in the brain and modulating the nAChRs function probably by binding to a specific site. Its success from a lab chemical to drug depends highly on its stability or shelf life. We have shown that 6-hydroxy-D-nicotine have a more potent antioxidant effect than nicotine when measured as FRAP units. Also, the pH stability of 6-hydroxy-D-nicotine is similar to nicotine, the compounds withstanding 48h exposure to pH above 3 up to 9 at room temperature

Antiamnesic and antioxidants effects of ferulago angulata essential oil against scopolamine-Induced memory impairment in laboratory rats

Ethical standard This study was approved by the Committee on the Ethics of Animal Experiments of the Alexandru Ioan Cuza University of Iasi (Permit Number: 2192) and also, efforts were made to minimize animal suffering and to reduce the number of animals used.Ferulago angulata (Apiaceae) is a shrub indigenous to western Iran, Turkey and Iraq. In traditional medicine, F. angulata is recommended for treating digestive pains, hemorrhoids, snake bite, ulcers and as sedative. In the present study, the effects of inhaled F. angulata essential oil (1 and 3 %, daily, for 21 days) on spatial memory performance were assessed in scopolamine-treated rats. Scopolamine-induced memory impairments were observed, as measured by the Y-maze and radial arm-maze tasks. Decreased activities of superoxide dismutase, glutathione peroxidase and catalase along with increase of acetylcholinesterase activity and decrease of total content of reduced glutathione were observed in the rat hippocampal homogenates of scopolamine-treated animals as compared with control. Production of protein carbonyl and malondialdehyde significantly increased in the rat hippocampal homogenates of scopolamine-treated animals as compared with control, as a consequence of impaired antioxidant enzymes activities. Additionally, in scopolamine- treated rats exposure to F. angulata essential oil significantly improved memory formation and decreased oxidative stress, suggesting memory-enhancing and antioxidant effects. Therefore, our results suggest that multiple exposures to F. angulata essential oil ameliorate scopolamine-induced spatial memory impairment by attenuation of the oxidative stress in the rat hippocampusEmel (Aydin) Akbaba was supported by LLP Erasmus (2013/2014) during her stage within Alexandru Ioan Cuza University of Iasi, Romania

Anxiolytic and antidepressant-like effects of Ferulago angulata essential oil in the scopolamine rat model of Alzheimer’s disease

Ferulago angulata subsp. carduchorum (Apiaceae) is a shrub indigenous to western Iran, Turkey and Iraq. In traditional medicine, F. angulata is recommended for treating digestive pains, haemorrhoids, snake bites, ulcers and as a sedative. The present study analysed the possible anxiolytic, antidepressant and antioxidant properties of F. angulata essential oil in a scopolamine-induced rat model of Alzheimer’s disease. The anxiolytic and antidepressant-like effects of F. angulata essential oil were studied using in vivo (elevated plus-maze and forced swimming tests) approaches. Also, the antioxidant activity in the amygdala was assessed using superoxide dismutase, glutathione peroxidase and catalase specific activities, the total content of the reduced glutathione, protein carbonyl and malondialdehyde levels. The scopolamine-treated rats exhibited the following: a decrease in the percentage of the time spent and the number of entries in the open armwithin the elevated plus-maze test and a decrease of swimming time and an increase of immobility time in the forced swimming test. Inhalation of F. angulata essential oil significantly exhibited anxiolytic and antidepressant-like effects and also antioxidant potential. Furthermore, in silico studies carried out by employing molecular docking experiments pointed to the existence of strong interactions of monoterpenes from F. angulata essential oil with anxiolytic and antidepressant effects with GABAA receptor. Our results suggest that the F. angulata essential oil inhalation ameliorates scopolamine-induced anxiety and depression by attenuation of the oxidative stress in the rat amygdala. Copyright © 2015 John Wiley & Sons, Ltd.TÜBİTAK program 2221-Fellowships for Visiting Scientists and Scientists on Sabbatical Leave (2014/2015) supported Prof. dr. Lucian Hritcu during the collaboration stay in Firat University, Elazig, Turkey

Experimental evidence of a xylose-catabolic pathway on the pAO1 megaplasmid of Arthrobacter nicotinovorans

The pAO1 megaplasmid of A. nicotinovorans consists of 165 ORF's related mainly to nicotine degradation, uptake and utilization of carbohydrates, amino acids and sarcosine. A putative sugar catabolic pathway consisting of 11 ORF's organized as a single operon were previously described. The current work brings experimental data supporting the existence of a D-Xylose catabolic pathway on the pAO1 megaplasmid. When grown on D-xylose containing media, the cells harboring the pAO1 megaplasmid grow to higher cell densities and also express the OxRe protein coded by the megaplasmid. A putative pathway similar to Weimberg pentose pathway is postulated, in which D-xylose is transported in the cell by the ABC-type transport system and then transformed using the putative sugar-dehidrogenase OxRe to D-xylonate, which is further degrated to 2-ketoglutarate and integrated into the general metabolism of the cel

APPLICATION OF PLANT GROWTH-PROMOTING RHIZOBACTERIA TO RUNNER BEAN INCREASES SEED CARBOHYDRATE AND PROTEIN YIELD

The potential of two rhizobacterial strains with plant growth promoting capabilities (mineral phosphate solubilization and IAA production traits) to influence the nutritive value of runner bean grains was assessed on plants cultivated in organic crop system. Seed inoculation with rhizobacterial strains improve the nutritive value of the harvested grains by enhancing the soluble protein content up to 11.97 % and total reducing carbohydrates content up to 28.97%. The number of fractions detected by SDS-PAGE analysis in the all extracts was around 20, without any significant differences between the control and the inoculated samples. Our study suggests that the two PGPR strains may be used as biofertilizer for vegetable production in sustainable and ecological agricultural systems

MOLECULAR GENE CLONING OF NICOTINE-DEHIDROGENASE FROM THE pAO1 MEGAPLASMID OF ARTHROBACTER NICOTINOVORANS

6-hydroxi-L-nicotine (6HNic) has an important potential as a drug for neuro-degenerative disorders and a  suitable simple and reliable method for obtaining contaminant-free 6HNic preparations is required. Here, we envision the in-vitro production of 6HNic by using purified nicotine-dehydrogenase (NDH) followed by HPLC or capillary electrophoresis techniques and we focus on the isolation and cloning of the three genes coding the NDH enzyme.  A PCR protocol was established for easy amplification and the DNA fragment containing the ndhLSM genes was directionally cloned into the pART2 vector

PRELIMINARY DATA REGARDING THE KINETIC PROPERTIES OF AN ALPHA-AMYLASE FROM ROBINIA PSEUDACACIA L. GERMINATED SEEDS

We have accomplished a partial purification of a alpha amylase from germinated seeds of Robinia pseudacacia L. by affinity precipitation. The key element is the sodium alginate, a polymer that proved affinity for this enzyme, and also has the propriety to reversibly precipitate with Ca2+. The enzyme binds to the alginate and the complex is precipitated with Ca2+. The amylase activity is recovered by dissolving the precipitate in 1M maltose and precipitating the alginate alone by addition of Ca2+. The  enzyme has a molecular weight estimated between 50 and 65 kDa, an optimum pH between 5 and 6; it is inhibited by ammonium sulfate and activated by CaCl2

Purification of a novel aldehide-dehidrogenase with wide substrate specificity

The pAO1 megaplasmid of Arthrobacter nicotinovorans encodes two different pathways: one for nicotine metabolism and a putative sugar catabolic pathway. An open reading frame, orf39, from the latter pathway was cloned, purified to homogenity and partially characterized. It consists of a monomeric NAD/NADP-dehidrogenase acting on various aldehyde as glutaraldehyde or butyraldehyde with an Cys residue in the active site. A possible catalytic mechanism is postulated

Plant growth promoting rhizobacteria can inhibit the in vitro germination of Glycine max L. seeds

Utilization of plant growth promoting rhizobacteria (PGPR) in order to increase the productivity may be a viable alternative to organic fertilizers. The main goal is to reduce the pollution and to preserve the environment in the spirit of an ecological agriculture. Because soybean represent a crop of major economic importance, a study was performed to analyze the impact of some rhizobacteria isolated from soybean roots on the on the germination process of Glycine max L. seeds, taking into account the aspartate- and alanin-aminotransferase activities. The results showed that in the early stages, rhizobacteria has an inhibitory effect on the germination process