1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide interference with Lowry method

1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) was tested for interference with the Lowry method of protein determination. The EDC interference was nearly additive at both 660 and 750 nm. Blue-colored complex developed in the case of EDC and showed maximum absorbance at 750 nm, similar to the bovine serum albumin (BSA) estimation. In time response analysis, blue-colored complex was developed after 30 min of incubation in both cases (EDC and BSA); therefore, it followed the same kinetic pattern of color development as that of BSA. Interference is believed to be caused by the reduction of the folin-ciocalteu reagent by EDC, resulting in increased blue-colored complex and apparently causing increased protein content of the sample.     

RGD mounted on an L-proline scaffold

The construction of an L-proline scaffold that enforces a defined beta-turn loop for RGD is reported. A key feature was the use of SASRIN (super acid sensitive resin) that allowed solid-phase synthesis of the tetrapeptide. A HATU-induced cyclization of the sequence was successful, followed by a single acid-promoted deprotection of the final product.     

Postembryonic development of the cervicothoracic skeleton of Euborellia annulipes (Lucas) (Dermaptera: Labiduridae)

The nymphal and adult cervicothoracic skeleton of Euborellia annulipes (Lucas) is described and discussed.     

DGAT1 deficiency decreases PPAR expression and does not lead to lipotoxicity in cardiac and skeletal muscle

Diacylglycerol (DAG) acyl transferase 1 (Dgat1) knockout ((-/-)) mice are resistant to high-fat-induced obesity and insulin resistance, but the reasons are unclear. Dgat1(-/-) mice had reduced mRNA levels of all three Ppar genes and genes involved in fatty acid oxidation in the myocardium of Dgat1(-/-) mice. Although DGAT1 converts DAG to triglyceride (TG), tissue levels of DAG were not increased in Dgat1(-/-) mice. Hearts of chow-diet Dgat1(-/-) mice were larger than those of wild-type (WT) mice, but cardiac function was normal. Skeletal muscles from Dgat1(-/-) mice were also larger. Muscle hypertrophy factors phospho-AKT and phospho-mTOR were increased in Dgat1(-/-) cardiac and skeletal muscle. In contrast to muscle, liver from Dgat1(-/-) mice had no reduction in mRNA levels of genes mediating fatty acid oxidation. Glucose uptake was increased in cardiac and skeletal muscle in Dgat1(-/-) mice. Treatment with an inhibitor specific for DGAT1 led to similarly striking reductions in mRNA levels of genes mediating fatty acid oxidation in cardiac and skeletal muscle. These changes were reproduced in cultured myocytes with the DGAT1 inhibitor, which also blocked the increase in mRNA levels of Ppar genes and their targets induced by palmitic acid. Thus, loss of DGAT1 activity in muscles decreases mRNA levels of genes involved in lipid uptake and oxidation.     

Expression of <Emphasis Type="Italic">Aprotinin</Emphasis> in Anther Causes Male Sterility in Tobacco var <Emphasis Type="Italic">Petit havana</Emphasis>

Expression of many proteinases has been documented during anther development. Although their roles are not completely understood, their inhibition could possibly result in impairment of anther development leading to male sterility. We proposed that such an impairment of anther development can be engineered in plants resulting in male sterile plants that can be used for hybrid seed production. Here, we report that anther-specific expression of Aprotinin gene (serine proteinase inhibitor) in tobacco has resulted in male sterility. Southern analysis and zymogram analysis confirmed the integration and expression of Aprotinin gene in the anthers of the transgenic plants. Transverse sections of anthers of transgenic male sterile plants showed damaged tapetum. The pollen germination in the transgenic plants ranged between 2% and 65% that confirmed the impairment in pollen production leading to male sterility and low seed yield. Thus, inhibition of serine proteinases that are expressed during anther development has resulted in impaired pollen production and male sterility, though the exact role of these proteinases in anther development still has to be elucidated.     

High-throughput enzymatic hydrolysis of lignocellulosic biomass via in-situ regeneration

The high cost of lignocellulolytic enzymes is one of the main barriers towards the development of economically competitive biorefineries. Enzyme engineering can be used to significantly increase the production rate as well as specific activity of enzymes. However, the success of enzyme optimization efforts is currently limited by a lack of robust high-throughput (HTP) cellulase screening platforms for insoluble pretreated lignocellulosic substrates. We have developed a cost-effective microplate based HTP enzyme-screening platform for ionic liquid (IL) pretreated lignocellulose. By performing in-situ biomass regeneration in micro-volumes, we can volumetrically meter biomass (sub-mg loading) and also precisely control the amount of residual IL for engineering novel IL-tolerant cellulases. Our platform only requires straightforward liquid-handling steps and allows the integration of biomass regeneration, washing, saccharification, and imaging steps in a single microtiter plate. The proposed method can be used to screen individual cellulases as well as to develop novel cellulase cocktails.     

Prevalence of the plasmid-mediated quinolone resistance determinants among clinical isolates of Shigella sp. in Andaman & Nicobar Islands, India

Aims: This study was carried out to find the prevalence of various plasmid‐mediated quinolone‐resistant (PMQR) determinants among the quinolone‐resistant clinical isolates of Shigella sp. from paediatric patients in Andaman & Nicobar Islands. Methods and Results: A total of 106 quinolone‐resistant Shigella isolates obtained from paediatric patients during hospital‐based surveillance from January 2003 to June 2010 were screened for the presence of various PMQR determinants. Of 106 isolates, 8 (7·5%) showed the presence of aac (6′)‐Ib‐cr and 3 (2·8%) harboured the qnrB genes with 2 (1·9%) of these isolates showing the presence of both. All the 9 isolates had uniform mutations in gyrA (S83L) and in parC (S80I). Conclusions: The prevalence of fluoroquinolone‐acetylating aminoglycoside acetyltransferase {aac (6′)‐Ib‐cr} gene is higher than qnrB gene among the clinical Shigella isolates. These PMQR determinants were detected in the Shigella isolates obtained from 2008–2010, indicating that it happens in a stepwise manner following the multiple mutations in quinolone resistance‐determining regions increase or extend resistance to quinolones or fluoroquinolones. Significance and Impact of Study: The prevalence of these genes are of grave concern as it may be horizontally transferred to other human pathogenic bacteria and can lead to therapeutic failure as a consequence of antimicrobial resistance, not only for the islands but also for the entire south‐east region. The results obtained should encourage further studies on the implications of the presence, distribution, association and variation of these determinants in our quest for understanding PMQR.     

Deficiency of lipoprotein lipase in neurons modifies the regulation of energy balance and leads to obesity

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Highlights? Mice with lipoprotein lipase deficiency in neurons (NEXLPL) are obese ? NEXLPL mice develop obesity by modifying both food intake and energy expenditure ? NEXLPL mice have increases in hypothalamic AgRP/NPY gene expression before obesity ? NEXLPL mice demonstrate deficiencies in n-3 fatty acids in the hypothalamus