Methylamine dehydrogenase and cytochrome c552 from the bacterium W3A1

We describe a two-step purification of the methoxatin-containing enzyme methylamine dehydrogenase from crude extracts of the bacterium W3A1, and a longer purification of cytochrome c552 from the same organism. Some of the kinetic properties of the dehydrogenase are presented, together with the demonstration that c552 is an electron acceptor for this enzyme. Cytochrome c552 is the only hemeprotein we observed in the visible spectrum of intact W3A1 cells that were grown under the same culture conditions used for the protein purifications. Addition of methylamine to whole cells causes an increase in the rate of O2 uptake together with an abrupt reduction of c552. We propose that, in vivo, the electrons from the amine reach the hemeprotein through the dehydrogenase.     

Anti-secretagogue effect of lithium on isolated rat islets of Langerhans

Administration of lithium carbonate solution (50 mg/kg, po, twice daily) to Charles Foster male albino rats for 45 consecutive days caused an intolerance to oral glucose. Inhibition in (pro)insulin biosynthesis followed by a significant fall in immunoreactive insulin release was seen in islets isolated from identically treated rats. As the activities of acid phosphatase and cathepsin B were unaltered, it is possible that the anti-secretagogue effect is sequential to inhibition of (pro)insulin biosynthesis by lithium.     

Deregulation of hepatic lipid metabolism associated with insulin resistance in rats subjected to chronic monocrotophos exposure

In our previous study, we demonstrated the potential of monocrotophos (MCP), an organophosphorus insecticide (OPI), to induce glucose intolerance, insulin resistance (IR), and dyslipidemia with hyperinsulinemia in rats after chronic exposure. As hyperinsulinemia is likely to exert an impact on hepatic lipid metabolism, we carried out this study to establish the effect of chronic MCP exposure (0.9 and 1.8 mg/kg/day for 180 days) on hepatic lipid metabolism in rats. The state of IR induced by MCP in rats was associated with an increase in the liver lipid content (triglyceride and cholesterol) and expression levels of sterol regulatory element‐binding proteins, PPARγ, acetyl‐CoA carboxylase, and fatty acid synthase in the liver. Similarly, activities of key enzymes (acetyl‐COA carboxylase, fatty acid synthase, lipin 1, malic enzyme, glucose‐6‐phosphate dehydrogenase, and glycerol‐3‐phosphate dehydrogenase), which regulate lipogenesis, were enhanced in livers of pesticide‐treated rats. A strong correlation was observed between insulin levels, hepatic lipid content, and plasma lipid profile in treated rats. Our study suggests that long‐term exposure to OPIs not only has a propensity to induce a state of hyperinsulinemic IR, but it is also associated with augmented hepatic lipogenesis, which may explain dyslipidemia induced by chronic exposure to MCP.     

Novel method to differentiate 3T3 L1 cells in vitro to produce highly sensitive adipocytes for a GLUT4 mediated glucose uptake using fluorescent glucose analog

Adipocytes play a vital role in glucose metabolism. 3T3 L1 pre adipocytes after differentiation to adipocytes serve as excellent in vitro models and are useful tools in understanding the glucose metabolism. The traditional approaches adopted in pre adipocyte differentiation are lengthy exercises involving the usage of IBMX and Dexamethasone. Any effort to shorten the time of differentiation and quality expression of functional differentiation in 3T3 L1 cells in terms of enhanced Insulin sensitivity has an advantage in the drug discovery process. Thus, there is a need to develop a new effective method of differentiating the pre adipocytes to adipocytes and to use such methods for developing efficacious therapeutic molecules. We observed that a combination of Dexamethasone and Troglitazone generated differentiated adipocytes over fewer days as compared to the combination of IBMX and Dexamethasone which constitutes the standard protocol followed in our laboratory. The experiments conducted to compare the quality of differentiation yielded by various differentiating agents indicated that the lipid droplet accumulation increased by 112 % and the GLUT4 mediated glucose uptake by 137 % in cells differentiated with Troglitazone and Dexamethasone than in cells differentiated traditionally. The comparative studies conducted for evaluating efficient measurable glucose uptake by GOPOD assay, radioactive ³H-2-deoxy-D-glucose assay and by non-radioactive 6-NBDG (fluorescent analog of glucose) indicated that the non-radioactive method using 6-NBDG showed a higher signal to noise ratio than the conventional indirect glucose uptake method (GOPOD assay) and the radioactive ³H-2-deoxy-D-glucose uptake method. Differentiated 3T3 L1 cells when triggered with 2.5 ng/mL of Insulin showed 3.3 fold more glucose uptake in non-radioactive method over the radioactive ³H-2-deoxy-D-glucose uptake method. The results of this study have suggested that a combination of Dexamethasone and Troglitazone for 3T3 L1 cell differentiation helps in better quality differentiation over a short period of time with increased sensitivity to Insulin. The application of these findings for developing new methods of screening novel Insulin mimetics and for evaluating the immunological responses has been discussed.     

Screening of banana bunchy top virus through multiplex PCR approach

Bunchy top disease caused by the banana bunchy top virus (BBTV) is a serious disease in hill banana. Detection of the BBTV infection in the planting material could help in the effective management of the disease. An attempt was made to develop a sensitive polymerase chain reaction (PCR) and multiplex PCR-based method for detection of BBTV in hill banana. DNA was isolated from the experimental plants at third and sixth months after planting. Multiplex PCR was done with Coat Protein (CP) and Replicase (Rep) gene-specific primer, and banana ethylene insensitive like protein (EISL) primer as internal control to identify failure in PCR reaction. This study revealed that multiplex PCR is effective for BBTV screening in hill banana with the advantage of overcoming the false positive in PCR amplification.     

PGPR mediated management of stem blight of Phyllanthus amarus (Schum and Thonn) caused by Corynespora cassiicola (Berk and Curt) Wei

Bacillus subtilis (BSCBE4), Pseudomonas chlororaphis (PA23), endophytic P. fluorescens (ENPF1) inhibited the mycelial growth of stem blight pathogen Corynespora casiicola (Berk and Curt)Wei under in vitro. All these bacterial isolates produced both hydroxamate and carboxylate type of siderophores. But the siderophore production was maximum with the isolate ENPF1. Delivering of talc based formulation of BSCBE4 through seedling dip and foliar application effectively reduced stem blight disease incidence and increased the dry matter production under pot culture and field conditions. Application of BSCBE4, PA23 and ENPF1 increased the defense related enzymes such as peroxidase, polyphenol oxidase, chitinase and β-1,3 glucanase in P. amarus up to ten days after challenge inoculation with C. cassicola. Native gel electrophoretic analysis revealed that challenge inoculation of pathogen with BSCBE4 and PA23 induced both peroxidase and polyphnol oxidase isoforms.     

Identification of Penicillin-binding proteins employing support vector machines and random forest

Penicillin-Binding Proteins are peptidases that play an important role in cell-wall biogenesis in bacteria and thus maintaining bacterial infections. A wide class of β-lactam drugs are known to act on these proteins and inhibit bacterial infections by disrupting the cell-wall biogenesis pathway. Penicillin-Binding proteins have recently gained importance with the increase in the number of multi-drug resistant bacteria. In this work, we have collected a dataset of over 700 Penicillin-Binding and non-Penicillin Binding Proteins and extracted various sequence-related features. We then created models to classify the proteins into Penicillin-Binding and non-binding using supervised machine learning algorithms such as Support Vector Machines and Random Forest. We obtain a good classification performance for both the models using both the methods.     

InDiaMed: A Comprehensive Database of Indian Medicinal plants for Diabetes

According to International Diabetes Federation (IDF), India has 62.4 million people with diabetes and by 2030 it is predicted that the number will rise to 100 million. Studies claim that there are around 410 experimentally proven Indian medicinal plants which have anti-diabetic activity, of which the mechanism of action of 109 plants has been elucidated or reported. So, the need of the hour is to explore the claims of Indian medicinal flora and open up the facets of many Indian plants which are being examined for their beneficial role in diabetes. So, we created a database (InDiaMed) of Indian medicinal plants that captures their role in anti-diabetic activity. InDiaMed''s features include chemical, pharmacological, biochemical and geographical information of the medicinal plant, scientifically relevant information of the plant, and the coherent research done on it in the field of diabetes. The database also includes the list of poly-herbal formulations which are used for treatment of diabetes in India.

Availability

http://www.indiamed.info