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101.
Nithya BabuRajendran Paaventhan Palasingam Kamesh Narasimhan Wenjie Sun Shyam Prabhakar Ralf Jauch Prasanna R. Kolatkar 《Nucleic acids research》2010,38(10):3477-3488
Smad1 is a downstream effector of the BMP signaling pathway that binds regulatory DNA to execute gene expression programs leading to, for example, the maintenance of pluripotency in mice. On the contrary, the TGF-β-activated Smad3 triggers strikingly different programs such as mesodermal differentiation in early development. Because Smad1 and Smad3 contain identical amino acids at the DNA contact interface it is unclear how they elicit distinctive bioactivities. Here, we report the crystal structure of the MH1 domain of Smad1 bound to a palindromic Smad binding element. Surprisingly, the DNA contact interface of Smad1 is drastically rearranged when compared to Smad3. The N-terminal helix 1 of Smad1 is dislodged from its intramolecular binding site and adopts a domain swapped arrangement with a symmetry-related molecule. As a consequence, helix 2 kinks away from the double helix disabling several key phosphate backbone interactions. Thermal melting analysis corroborates a decompacted conformation of Smad1 and DNA binding assays indicate a lower overall affinity of Smad1 to DNA but increased cooperativity when binding to palindromic DNA motifs. These findings suggest that Smad1 and Smad3 evolved differential qualities to assemble on composite DNA elements and to engage in co-factor interactions by remodeling their N-termini. 相似文献
102.
Sukanta K. Sabut Prasanna K. Lenka Ratnesh Kumar Manjunatha Mahadevappa 《Journal of electromyography and kinesiology》2010,20(6):1170-1177
ObjectiveTo investigate the effects of functional electrical stimulation (FES) combined with conventional rehabilitation program on the effort and speed of walking, the surface electromyographic (sEMG) activity and metabolic responses in the management of drop foot in stroke subjects.MethodsFifteen patients with a drop foot resulting from stroke at least 3 months prior to the start of the trial took part in this study. All subjects were treated 1 h a day, 5 days a week, for 12 weeks, including conventional stroke rehabilitation program and received 30 min of FES to the tibialis anterior (TA) muscle of the paretic leg in clinical settings. Baseline and post-treatment measurements were made for temporal and spectral EMG parameters of TA muscle, walking speed, the effort of walking as measured by physiological cost index (PCI) and metabolic responses.ResultsThe experimental results showed a significant improvement in mean-absolute-value (21.7%), root-mean-square (66.3%) and median frequency (10.6%) of TA muscle EMG signal, which reflects increased muscle strength. Mean increase in walking speed was 38.7%, and a reduction in PCI of 34.6% between the beginning and at end of the trial. Improvements were also found in cardiorespiratory responses with reduction in oxygen consumption (24.3%), carbon dioxide production (19.9%), heart rate (7.8%) and energy cost (22.5%) while walking with FES device.ConclusionsThe results indicate that the FES may be a useful therapeutic tool combined with conventional rehabilitation program to improve the muscle strength, walking ability and metabolic responses in the management of drop foot with stroke patients. 相似文献
103.
Safaa G. Kumari Brendan Rodoni Heinrich-Josef Vetten Mai Hlaing Loh Angela Freeman Joop van Leur Shiying Bao Xiaoming Wang 《Journal of Phytopathology》2010,158(1):35-39
A virus disease of faba bean ( Vicia faba L.) in China, characterized by leaf yellowing and rolling and plant stunting, was shown to be caused by a virus of the genus Nanovirus based on serological reactions to nanovirus-specific monoclonal antibodies and the generation of polymerase chain reaction amplicons using nanovirus-specific primers. To identify the faba bean-infecting nanovirus, regions of the DNA components encoding the master replication initiator protein and capsid protein of two nanovirus isolates from China were cloned, sequenced and compared with those of other members of the genus Nanovirus . The two Chinese virus isolates shared nucleotide sequence identities ranging from 95 to 98% with the type isolate of Milk vetch dwarf virus (MDV) from Japan. They were thus identified as isolates of MDV, a virus so far known to cause important diseases of legumes in Japan. This is the first record of MDV-infecting faba bean in China. 相似文献
104.
Purushothaman S Prasanna R Niranjana P Raghunathan R Nagaraj S Rengasamy R 《Bioorganic & medicinal chemistry letters》2010,20(24):7288-7291
Synthesis of a series of novel hexahydrochromenopyrrole analogues has been accomplished through an intramolecular 1,3-dipolar cycloaddition (1,3-DC reaction) of azomethine ylides, generated by the aldehyde induced decarboxylation of secondary amino acids. These compounds were screened for antibacterial and antifungal activities against six human pathogenic bacteria and three human pathogenic fungi and found to have good antimicrobial properties against most of the microorganisms. 相似文献
105.
R. Prasanna A. Sood P. Jaiswal S. Nayak V. Gupta V. Chaudhary M. Joshi C. Natarajan 《Applied Biochemistry and Microbiology》2010,46(2):119-134
Cyanobacteria are a simple, but primitive and diverse group of microorganisms, with characteristics in common to both bacteria and algae. Their success as a group in a wide range of habitats has been attributed to their unique physiological characters and high adaptive ability under a wide range of environmental conditions. The potential of cyanobacteria as a source of a variety of compounds such as polysaccharides, lipids, proteins, vitamins, sterols, enzymes, pharmaceuticals and other fine chemicals is well recognized, and their demand is now on an increasing trend. This compilation reviews the salient advances in the discovery of bioactive compounds from cyanobacteria and their significance in agriculture and industry. 相似文献
106.
The activity and subunit amounts of V-ATPase and V-PPase in various plants of Butea monosperma Taub. (Fabaceae) (ver. Dhak; Palas) growing as a natural inhabitant in varying stress conditions in southeast Rajasthan were studied. Western blot analysis followed by immunological quantification of V-ATPase subunits using specific polyclonal antibodies showed that the subunits A, B, D, E, and c are clearly detectable in all plants, with A, B, and c appearing as intense bands. The other subunits of V-ATPase, viz., C, a, and d, were also detected in majority of the plants. Various subunits exhibited variations in their protein amount in different plants. Besides, a few other clear bands were also detected. Of these, the 30- and 29-kD bands may possibly be Di and Ei. Furthermore, a clear band of V-PPase corresponding to 67–70 kD was also detected. A comparison of the V-ATPase and V-PPase activity revealed that Butea plants in the upper region of the study site showed 70% and 39% higher activity, respectively. Furthermore, the immunological quantification showed that the V-ATPase and V-PPase protein amounts are also higher in the upper Butea plants which have drought stress and, moreover, are also exposed to stronger light intensities for relatively longer duration. 相似文献
107.
Ghanshyam S. Chauhan Kalpana Chauhan Sandeep Chauhan Sunil Kumar Anita Kumari 《Carbohydrate polymers》2007,70(4):415-421
Pine needles and their carboxymethyl forms were functionalized by network formation with 2-acrylamido-2-methylpropanesulphonic acid (AAmPSA) in the presence of N,N-methylene bisacrylamide. N-Tetramethylethylene diamine and ammonium persulfate were used as accelerator-initiator systems to prepare these hydrogels. The hydrogels were characterized by FTIR, SEM, and nitrogen analysis and for water uptake capacities before and after metal ion sorption with a view to evaluating their use in the removal of toxic ionic species from waste water. A detailed study of Cr6+ adsorption was carried out as a function of time, temperature, pH, and ionic strength. The thermodynamic parameters of adsorption such as ΔH0, ΔS0, and ΔG0 have been evaluated to understand the underlying mechanism of adsorption. In order to understand their reusability in possible technological applications, biodegradability of these hydrogels and their precursors was studied. 相似文献
108.
Ras proteins regulate a wide range of biological processes by interacting with a variety of effector proteins. In addition to the known role in tumorigensis, the activated form of Ras exhibits growth-inhibitory effects by unknown mechanisms. Several Ras effector proteins identified as mediators of apoptosis and cell-cycle arrest also exhibit properties normally associated with tumor suppressor proteins. Here, we show that Ras effector RASSF5/NORE-1 binds strongly to K-Ras but weakly to both N-Ras and H-Ras. RASSF5 was found to localize both in the nucleus and the nucleolus in contrast to other Ras effector proteins, RASSF1C and RASSF2, which are localized in the nucleus and excluded from nucleolus. A 50 amino acid residue transferable arginine-rich nucleolar localization signal (NoLS) identified in RASSF5 is capable of interacting with importin-beta and transporting the cargo into the nucleolus. Surprisingly, similar arginine-rich signals identified in RASSF1C and RASSF2 interact with importin-alpha and transport the heterologous cytoplasmic proteins to the nucleus. Interestingly, mutation of arginine residues within these nuclear targeting signals prevented interaction of Ras effector proteins with respective transport receptors and abolished their nuclear translocation. These results provide evidence for the first time that arginine-rich signals are able to recognize different nuclear import receptors and transport the RASSF proteins into distinct sub-cellular compartments. In addition, our data suggest that the nuclear localization of RASSF5 is critical for its cell growth control activity. Together, these data suggest that the transport of Ras effector superfamily proteins into the nucleus/nucleolus may play a vital role in modulating Ras-mediated cell proliferation during tumorigenesis. 相似文献
109.
Gholap AR Toti KS Shirazi F Kumari R Bhat MK Deshpande MV Srinivasan KV 《Bioorganic & medicinal chemistry》2007,15(21):6705-6715
A series of 2-amino-5-oxo-4-phenyl-5,6,7,8-tetrahydroquinoline-3-carbonitrile and various analogues have been synthesized in excellent isolated yields starting from various arylidenemalononitrile and 3-amino-2-cyclohexen-1-one in 1-propanol as solvent at reflux temperature in the absence of any added catalyst. All the synthesized compounds were evaluated for their antifungal activity. The relationship between functional group variation and biological activity of the evaluated compounds is discussed in the article. 相似文献
110.
Saswati Nayak Radha Prasanna Boddupalli M. Prasanna Dina B. Sahoo 《World journal of microbiology & biotechnology》2007,23(11):1575-1584
A set of 24 strains belonging to the genus Anabaena (Phylum Cyanobacteria), isolated from diverse geographic locations in India, were evaluated along with three International
type strains of Anabaena (ATCC 29414, ATCC 29208 and ATCC 27899) for their morphological, physiological and biochemical diversity. The morphological
dataset, consisting of 58 variants for 15 characters, and SDS-PAGE protein profiles comprising 17 polymorphic bands were utilized
to differentiate the selected Anabaena strains and explore the patterns of diversity through cluster analysis. Physiological and biochemical characterization with
respect to nitrogen fixation and accumulation of chlorophyll and phycobiliproteins led to the identification of some highly
promising Anabaena strains for use as biofertilizers and source of pigments. The study highlighted the tremendous inter and intraspecific diversity
within the Anabaena isolates and indicated the potential as well as constraints of the morphological and protein profiling datasets for unambiguous
differentiation and analyses of diversity among the Anabaena strains. 相似文献