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1.
Saijai Panwichian Duangporn Kantachote Banjong Wittayaweerasak Megharaj Mallavarapu 《World journal of microbiology & biotechnology》2010,26(12):2199-2210
In order to remove heavy metals (HMs) from contaminated shrimp pond at the highest concentrations found of; 0.75 mg/l Cd2+, 62.63 mg/l Pb2+, 34.60 mg/l Cu2+ and 58.50 mg/l Zn2+, two strains of purple nonsulfur bacteria isolated from shrimp ponds (NW16 and KMS24) were investigated for their ability
to immobilize HMs in 3% NaCl in both microaerobic-light and aerobic-dark conditions. Based on metabolic inhibition and metabolic-dependent
studies, it was concluded that both strains removed HMs using biosorption and also bioaccumulation. The efficiency of removal
by both strains with both incubating conditions tested was in the order of lead (Pb) > copper (Cu) > zinc (Zn) > cadmium (Cd).
Optimal conditions for removal of HMs by strain NW16 were; cells in the log phase at 4.5 mg DCW/ml, pH 6.0, and 30°C for 30 min.
With microaerobic-light conditions, the relative percent removal of HMs was: Pb, 83; Cu, 59; Zn, 39; Cd, 23 and slightly more
with the aerobic-dark conditions (Pb, 90; Cu, 69; Zn, 46; Cd, 28). Cells in the log phase at 5.0 mg DCW/ml, pH 5.5, and 35°C
for 45 min were optimal conditions for strain KMS24 and there were no significant differences for the removal percentages
of HMs with either incubating conditions (averages: Pb, 96; Cu, 75; Zn, 46; Cd, 30). The presence of Ca2+ and Mg2+ significantly decreased the removal capacity of HMs for both strains. 相似文献
2.
Tim Ammon ;Shravan Kumar Mishra ;Kaja Kowalska ;Grzegorz M. Popowicz ;Tad A. Holak ;Stefan Jentsch 《分子细胞生物学报》2014,(4):312-323
Different from canonical ubiquitin-like proteins, Hub1 does not form covalent conjugates with substrates but binds proteins noncovalently. In Socchoromyces cerevisioe, Hub1 associates with spUceosomes and mediates alternative splicing of SRCI, without affecting pre-mRNA splicing generaity. Human Hub1 is highty similar to its yeast homotog, but its cellular function remains largely unexplored. Here, we show that human Hub1 binds to the spliceosomal protein Snu66 as in yeast; however, unlike its 5. cerevisioe homolos, human Hub1 is essential for viability. Prolonged in vivo depletion of human Hub1 leads to various cellular defects, including splicing speckle abnormalities, partial nuclear retention of mRNAs, mitotic catastrophe, and consequently cell death by apoptosis. Early consequences of Hub1 depletion are severe splicing defects, however, only for specific splice sites leading to exon skipping and intron retention. Thus, the ubiquitin-iike protein Hub1 is not a canonlcal spliceosomal factor needed generally for splicing, but rather a modulator of spliceosome performance and facilitator of alternative splicing. 相似文献
3.
Sandeep Kumar Mulukala Narasimha Shravan Kumar Gunda Mahmood Shaik 《Journal of molecular modeling》2013,19(4):1891-1900
The cytoplasm of a eukaryotic cell consists of a wide variety of membrane bound cell organelles and continuous flow of proteins amongst these organelles is a major challenge and must be stringently maintained in order to continue the correct biochemical functioning inside a cell. The transportation of various proteins amongst these organelles is facilitated by a vast Tubulo-vesicular network mediated by carrier proteins. The Rabs belong to small G proteins super family involved in the regulation and vesicle transport in between the organelles by shuttling between the active GTP and inactive GDP bound states. In this paper we put forth the homology modeling and docking studies of Rab6A proteins (Mus musculus, Gallus gallus and Caenorhabditis elegans) with GTP, GMP-PNP and GDP molecules and a comparative study between these proteins is done to identify key residues out of which serine of the phosphate binding loop (P – loop) and aspartic acid showed prominent interactions with the GTP, GDP and GMP-PNP nucleotides and cogitate that aspartic acid might also help in the stabilization of the switch I region of the Rab proteins besides serine. 相似文献
4.
Bala Divya Mallavarapu Maaged Abdullah Shalini Saxena 《Journal of biomolecular structure & dynamics》2013,31(14):3751-3763
AbstractTuberculosis (TB) is a contagious disease caused by Mycobacterium tuberculosis (M.tb) or tubercule bacillus, and H37Rv is the most studied clinical strain. The recent development of resistance to existing drugs is a global health-care challenge to control and cure TB. Hence, there is a critical need to discover new drug targets in M.tb. The members of peptidoglycan biosynthesis pathway are attractive target proteins for antibacterial drug development. We have performed in silico analysis of M.tb MraY (Rv2156c) integral membrane protein and constructed the three-dimensional (3D) structure model of M.tb MraY based on homology modeling method. The validated model was complexed with antibiotic muraymycin D2 (MD2) and was used to generate structure-based pharmacophore model (e-pharmacophore). High-throughput virtual screening (HTVS) of Asinex database and molecular docking of hits was performed to identify the potential inhibitors based on their mode of interactions with the key residues involved in M.tb MraY–MD2 binding. The validation of these molecules was performed using molecular dynamics (MD) simulations for two best identified hit molecules complexed with M.tb MraY in the lipid bilayer, dipalmitoylphosphatidyl-choline (DPPC) membrane. The results indicated the stability of the complexes formed and retained non-bonding interactions similar to MD2. These findings may help in the design of new inhibitors to M.tb MraY involved in peptidoglycan biosynthesis. 相似文献
5.
6.
Chakkiyath Madayi Roshith Ranjan Kumar Manna Vettath Raghavan Suresh Srikanta Samanta Raju Baitha Satish K. Koushlesh Sibina Mol Salim Lohith Kumar Shravan Kumar Sharma Ashis Roychowdhury Muttanahalli Eregowda Vijayakumar Rakesh Pal Basanta Kumar Das 《Zeitschrift fur angewandte Ichthyologie》2021,37(5):795-798
The present study estimated length–weight relationships (LWRs) for six indigenous fish species (Barilius gatensis, Salmostoma acinaces, S. boopis, Puntius amphibius, Hemibagrus punctatus and Ambassis miops) based on specimens collected from River Cauvery (including estuary) during July 2017–January 2020. The sampling surveys were carried out in three distinct sampling seasons, viz., the pre-monsoon (March–May), the monsoon (July–October) and the post-monsoon (November–February). Majority of the fish specimens dealt in the study were collected from multi-meshed monofilament gill nets (mesh sizes 18, 30, 45, 60, 90, 110, 120 and 150 mm) operated by local fishers. For those sites situated in the protected areas, sampling was carried out by cast nets with prior permission from the local administration and the collected fishes were released back into river after length–weight measurements. The length measurements were noted as total length (TL) measured to the nearest 0.1 cm by using a digital Vernier caliper. A digital balance was used for weight measurements with an accuracy of 0.01 g. The study recorded a new maximum length of 48 cm for H. punctatus. The LWR data generated from the present study are significant for proper assessment of the stock status and their management, if collected together with other essential biological and physical parameters. 相似文献
7.
The intrinsic mechanisms that promote the degeneration of retinal ganglion cells (RGCs) following the activation of N-Methyl-D-aspartic acid-type glutamate receptors (NMDARs) are unclear. In this study, we have investigated the role of downstream regulatory element antagonist modulator (DREAM) in NMDA-mediated degeneration of the retina. NMDA, phosphate-buffered saline (PBS), and MK801 were injected into the vitreous humor of C57BL/6 mice. At 12, 24, and 48 hours after injection, expression of DREAM in the retina was determined by immunohistochemistry, western blot analysis, and electrophoretic mobility-shift assay (EMSA). Apoptotic death of cells in the retina was determined by terminal deoxynucleotidyl transferace dUTP nick end labeling (TUNEL) assays. Degeneration of RGCs in cross sections and in whole mount retinas was determined by using antibodies against Tuj1 and Brn3a respectively. Degeneration of amacrine cells and bipolar cells was determined by using antibodies against calretinin and protein kinase C (PKC)-alpha respectively. DREAM was expressed constitutively in RGCs, amacrine cells, bipolar cells, as well as in the inner plexiform layer (IPL). NMDA promoted a progressive decrease in DREAM levels in all three cell types over time, and at 48 h after NMDA-treatment very low DREAM levels were evident in the IPL only. DREAM expression in retinal nuclear proteins was decreased progressively after NMDA-treatment, and correlated with its decreased binding to the c-fos-DRE oligonucleotides. A decrease in DREAM expression correlated significantly with apoptotic death of RGCs, amacrine cells and bipolar cells. Treatment of eyes with NMDA antagonist MK801, restored DREAM expression to almost normal levels in the retina, and significantly decreased NMDA-mediated apoptotic death of RGCs, amacrine cells, and bipolar cells. Results presented in this study show for the first time that down-regulation of DREAM promotes the degeneration of RGCs, amacrine cells, and bipolar cells. 相似文献
8.
Gauri Saxena Suchitra Banerjee Laiq-ur-Rahman Praveen Chandra Verma G. R. Mallavarapu Sushil Kumar 《Plant Cell, Tissue and Organ Culture》2007,90(2):215-223
Transgenic plants of rose-scented geranium (Pelargonium graveolens cv. Hemanti) have been produced from Agrobacterium rhizogenes (strains A4 and LBA9402) mediated hairy root cultures. Amongst the explants tested, leaves were most responsive followed by the petioles
and internodal segments, respectively. The A4 strain performed better for all the three explants both in terms of frequency of response and time requirement for hairy
root induction. Transgenic shoots could be obtained by spontaneous regeneration without intervening callus phase amongst 16%
and 12% root lines of A4 and LBA 9402 origin, respectively, or they were induced in 29% and 22% hairy root lines of A4 and LBA9402 origin, respectively, with different hormonal supplementation. These transgenic plants showed 30% survival as
against 90% of their control under the confined environment of glasshouse. The transgenic plants were of similar morphotype
having increased branching, higher number of leaves with increased dentations, short and round stature, highly branched root
system and absence of leaf wrinkling. These transgenic plants showed opine positive results even after 5 months of their transfer
to the glasshouse. The essential oil compositions of 81% of these transgenics were qualitatively similar to that of the wild
type parent. However, two transgenic plants (LZ-3 and 14TG) showed increase in concentrations of geraniol and geranyl esters
signifying improved oil quality with respect to the citronellol:geraniol ratio. These two oils having better olfactory value
represent an improvement over that of the wild type parent from the commercial point of view. 相似文献
9.
Malkeet Singh Bahia Shravan Kumar Gunda Shwetha Reddy Gade Saikh Mahmood Ravikumar Muttineni Om Silakari 《Journal of molecular modeling》2011,17(1):9-19
Anthranilic acid based derivatives (ANTs) have been identified as a novel class of potent tumor necrosis factor-α converting
enzyme (TACE) inhibitors. A computational strategy based on molecular docking studies, followed by CoMFA and CoMSIA analyses
has been performed to elucidate the atomic details of the TACE/ANT interactions and also to identify the most important features
impacting TACE inhibitory activity of ANTs. The CoMSIA model resulted to be slightly more predictive than CoMFA model, and
gave conventional r2 0.991, rcv2 0.793, q2 0.777, SEE 0.050, F-value 655.610, and rtest2 0.871. The 3D-QSAR field contributions and the structural features of the TACE binding site showed a good correlation. These
studies will be useful to design new TACE inhibitors with improved potency. 相似文献
10.
Ramesh Gannu Chinna Reddy Palem Shravan Kumar Yamsani Vamshi Vishnu Yamsani Madhusudan Rao Yamsani 《AAPS PharmSciTech》2010,11(2):976-985
The purpose of the present study was to develop and optimize reservoir-based transdermal therapeutic system (TTS) for buspirone
(BUSP), a low bioavailable drug. A three-factor, three-level Box–Behnken design was employed to optimize the TTS. Hydroxypropyl
methylcellulose, d-limonene and propylene glycol were varied as independent variables; cumulative amount permeated across rat abdominal skin
in 24 h, flux and lag time were selected as dependent variables. Mathematical equations and response surface plots were used
to relate the dependent and independent variables. The statistical validity of polynomials was established, and optimized
formulation factors were selected by feasibility and grid search. Validation of the optimization study with seven confirmatory
runs indicated high degree of prognostic ability of response surface methodology. BUSP-OPT (optimized formulation) showed
a flux 104.6 μg cm−2 h−1, which could meet target flux. The bioavailability studies in rabbits showed that about 2.65 times improvement (p < 0.05) in bioavailability, after transdermal administration of BUSP-OPT compared to oral solution. The ex vivo–in vivo correlation was found to have biphasic pattern and followed type A correlation. Reservoir-based TTS for BUSP was developed
and optimized using Box–Behnken statistical design and could provide an effective treatment in the management of anxiety. 相似文献