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681.
Developmental variability was introduced into Withania somnifera using genetic transformation by Agrobacterium rhizogenes, with the aim of changing withasteroid production. Inoculation of W. somnifera with A. rhizogenes strains LBA 9402 and A4 produced typical transformed root lines, transformed callus lines, and rooty callus lines with simultaneous
root dedifferentiation and redifferentiation. These morphologically distinct transformed lines varied in T-DNA content, growth
rates, and withasteroid accumulation. All of the lines with the typical transformed root morphology contained the TL T-DNA, and 90% of them carried the TR T-DNA, irrespective of the strain used for infection. Accumulation of withaferin A was maximum (0.44% dry weight) in the
transformed root line WSKHRL-1. This is the first detection of withaferin A in the roots of W. somnifera. All of the rooty callus lines induced by strain A4 contained both the TL and the TR-DNAs. In contrast, 50% of the rooty-callus lines obtained with strain LBA 9402 contained only the TR T-DNA. All the rooty callus lines accumulated both withaferin A and withanolide D. The callusing lines induced by LBA 9402
lacked the TL T-DNA genes, while all the callusing lines induced by strain A4 contained the TL DNA. Four of these callus lines produced both withaferin A (0.15–0.21% dry weight) and withanolide D (0.08–0.11% dry weight),
and they grew faster than the transformed root lines. This is the first report of the presence of withasteroids in undifferentiated
callus cultures of W. somnifera. 相似文献
682.
Acta Biotheoretica - We investigate the epistemological consequences of a positive polymerase chain reaction SARS-CoV test for two relevant hypotheses: (i) V is the hypothesis that an individual... 相似文献
683.
684.
Ya-Juan Wang Bamidele O. Tayo Anupam Bandyopadhyay Heming Wang Tao Feng Nora Franceschini Hua Tang Jianmin Gao Yun Ju Sung the COGENT BP consortium Robert C. Elston Scott M. Williams Richard S. Cooper Ting-Wei Mu Xiaofeng Zhu 《PLoS genetics》2014,10(9)
High blood pressure (BP) is the most common cardiovascular risk factor worldwide and a major contributor to heart disease and stroke. We previously discovered a BP-associated missense SNP (single nucleotide polymorphism)–rs2272996–in the gene encoding vanin-1, a glycosylphosphatidylinositol (GPI)-anchored membrane pantetheinase. In the present study, we first replicated the association of rs2272996 and BP traits with a total sample size of nearly 30,000 individuals from the Continental Origins and Genetic Epidemiology Network (COGENT) of African Americans (P = 0.01). This association was further validated using patient plasma samples; we observed that the N131S mutation is associated with significantly lower plasma vanin-1 protein levels. We observed that the N131S vanin-1 is subjected to rapid endoplasmic reticulum-associated degradation (ERAD) as the underlying mechanism for its reduction. Using HEK293 cells stably expressing vanin-1 variants, we showed that N131S vanin-1 was degraded significantly faster than wild type (WT) vanin-1. Consequently, there were only minimal quantities of variant vanin-1 present on the plasma membrane and greatly reduced pantetheinase activity. Application of MG-132, a proteasome inhibitor, resulted in accumulation of ubiquitinated variant protein. A further experiment demonstrated that atenolol and diltiazem, two current drugs for treating hypertension, reduce the vanin-1 protein level. Our study provides strong biological evidence for the association of the identified SNP with BP and suggests that vanin-1 misfolding and degradation are the underlying molecular mechanism. 相似文献
685.
Susmita Bandyopadhyay Boon Yee Ng Charmaine Chong Ming Zhen Lim Sonia Kiran Gill Ke Hui Lee J Sivaraman Chiradip Chatterjee 《Journal of peptide science》2014,20(10):811-821
Brevinin‐2‐related peptide (BR‐II), a novel antimicrobial peptide isolated from the skin of frog, Rana septentrionalis, shows a broad spectrum of antimicrobial activity with low haemolytic activity. It has also been shown to have antiviral activity, specifically to protect cells from infection by HIV‐1. To understand the active conformation of the BR‐II peptide in membranes, we have investigated the interaction of BR‐II with the prokaryotic and eukaryotic membrane‐mimetic micelles such as sodium dodecylsulfate (SDS) and dodecylphosphocholine (DPC), respectively. The interactions were studied using fluorescence and circular dichroism (CD) spectroscopy. Fluorescence experiments revealed that the N‐terminus tryptophan residue of BR‐II interacts with the hydrophobic core of the membrane mimicking micelles. The CD results suggest that interactions with membrane‐mimetic micelles induce an α‐helix conformation in BR‐II. We have also determined the solution structures of BR‐II in DPC and SDS micelles using NMR spectroscopy. The structural comparison of BR‐II in the presence of SDS and DPC micelles showed significant conformational changes in the residues connecting the N‐terminus and C‐terminus helices. The ability of BR‐II to bind DNA was elucidated by agarose gel retardation and fluorescence experiments. The structural differences of BR‐II in zwitterionic versus anionic membrane mimics and the DNA binding ability of BR‐II collectively contribute to the general understanding of the pharmacological specificity of this peptide towards prokaryotic and eukaryotic membranes and provide insights into its overall antimicrobial mechanism. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
686.
Parth Sarthi Sen Gupta Shyamashree Banerjee Rifat Nawaz Ul Islam Sudipta Mondal Buddhadev Mondal Amal K Bandyopadhyay 《Bioinformation》2014,10(2):105-107
In the genomic and proteomic era, efficient and automated analyses of sequence properties of protein have become an important
task in bioinformatics. There are general public licensed (GPL) software tools to perform a part of the job. However, computations
of mean properties of large number of orthologous sequences are not possible from the above mentioned GPL sets. Further, there is
no GPL software or server which can calculate window dependent sequence properties for a large number of sequences in a single
run. With a view to overcome above limitations, we have developed a standalone procedure i.e. PHYSICO, which performs various
stages of computation in a single run based on the type of input provided either in RAW-FASTA or BLOCK-FASTA format and
makes excel output for: a) Composition, Class composition, Mean molecular weight, Isoelectic point, Aliphatic index and GRAVY,
b) column based compositions, variability and difference matrix, c) 25 kinds of window dependent sequence properties. The
program is fast, efficient, error free and user friendly. Calculation of mean and standard deviation of homologous sequences sets,
for comparison purpose when relevant, is another attribute of the program; a property seldom seen in existing GPL softwares.
Availability
PHYSICO is freely available for non-commercial/academic user in formal request to the corresponding author ni.ca.vinurub.hcetoib@eejrenabka 相似文献687.
688.
689.
Huang-Wen Chen Sunayan Bandyopadhyay Dennis E Shasha Kenneth D Birnbaum 《BMC evolutionary biology》2010,10(1):357
Background
Gene duplication can lead to genetic redundancy, which masks the function of mutated genes in genetic analyses. Methods to increase sensitivity in identifying genetic redundancy can improve the efficiency of reverse genetics and lend insights into the evolutionary outcomes of gene duplication. Machine learning techniques are well suited to classifying gene family members into redundant and non-redundant gene pairs in model species where sufficient genetic and genomic data is available, such as Arabidopsis thaliana, the test case used here. 相似文献690.
The objective of the present study was to prepare mucoadhesive in situ nasal gels with mucilage isolated from fig fruits (Ficus carica, family: Moraceae) containing midazolam hydrochloride. Nasal gels of midazolam were prepared using three different concentrations
(0.5%, 1.0% and 1.5% w/v) of F. carica mucilage (FCM) and synthetic polymers (hydroxypropylmethyl cellulose and Carbopol 934). Evaluation of FCM showed that it
was as safe as the synthetic polymers for nasal administration. In situ gels were prepared with mixture Pluronic F127 and mucoadhesive agents. Evaluation of the prepared gels was carried out, including
determination of viscosity, texture profile analysis and mucoadhesive strength. In vitro drug permeation study was conducted with the gels prepared with and without permeation enhancer (0.5% w/v sodium taurocholate) using excised goat nasal mucosa. In vitro permeation profiles were evaluated, and histological study of nasal mucosae before and after permeation study was also conducted
to determine histological change, if any. In vivo experiments conducted in rabbits further confirmed that in situ nasal gels provided better bioavailability of midazolam than the gels prepared from synthetic mucoadhesive polymers. It was
observed that the nasal gel containing 0.5% FCM and 0.5% sodium taurocholate exhibited appropriate rheological, mechanical
and mucoadhesive properties and showed better drug release profiles. Moreover, this formulation produced no damage to the
nasal mucosa that was used for the permeation study, and absolute bioavailability was also higher compared to gels prepared
from synthetic polymers. 相似文献