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241.
242.
Mrinalini Muralidharan Kristina Buss Katherine E. Larrimore Nicholas A. Segerson Latha Kannan Tsafrir S. Mor 《Plant molecular biology》2013,81(6):565-576
Acetylcholinesterase is an enzyme that is intimately associated with regulation of synaptic transmission in the cholinergic nervous system and in neuromuscular junctions of animals. However the presence of cholinesterase activity has been described also in non-metazoan organisms such as slime molds, fungi and plants. More recently, a gene purportedly encoding for acetylcholinesterase was cloned from maize. We have cloned the Arabidopsis thaliana homolog of the Zea mays gene, At3g26430, and studied its biochemical properties. Our results indicate that the protein encoded by the gene exhibited lipase activity with preference to long chain substrates but did not hydrolyze choline esters. The At3g26430 protein belongs to the SGNH clan of serine hydrolases, and more specifically to the GDS(L) lipase family. 相似文献
243.
244.
Kannan Badri Narayanan Natarajan Sakthivel 《World journal of microbiology & biotechnology》2013,29(11):2207-2211
The size and morphology determines the thermodynamic, physical and electronic properties of metal nanoparticles. The extracellular synthesis of gold nanoparticles by fungus, Cylindrocladium floridanum, which acts as a source of reducing and stabilizing agent has been described. The synthesized nanoparticles were characterized using techniques such as UV–Vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy, energy dispersive X-ray analysis (EDAX), and high-resolution transmission electron microscopy (HR-TEM). Based on the evidence of HR-TEM, the synthesized particles were found to be spherical with an average size of 19.05 nm. Powder XRD pattern proved the formation of (111)-oriented face-centered cubic crystals of metallic gold. This microbial approach by fungus for the green synthesis of spherical gold nanoparticles has many advantages such as economic viability, scaling up and environment friendliness. 相似文献
245.
King Solomon Ebenezer Ramesh Nachimuthu Prabha Thiagarajan Rajesh Kannan Velu 《Bioinformation》2013,9(15):792-795
Any novel protein introduced into the GM crops need to be evaluated for cross affinity on living organisms. Many researchers are
currently focusing on the impact of Bacillus thuringiensis cotton on soil and microbial diversity by field experiments. In spite of this,
in silico approach might be helpful to elucidate the impact of cry genes. The crystal a protein which was produced by Bt at the time
of sporulation has been used as a biological pesticide to target the insectivorous pests like Cry1Ac for Helicoverpa armigera and
Cry2Ab for Spodoptera sp. and Heliothis sp. Here, we present the comprehensive in silico analysis of Cry1Ac and Cry2Ab proteins
with available in silico tools, databases and docking servers. Molecular docking of Cry1Ac with procarboxypeptidase from
Helicoverpa armigera and Cry1Ac with Leucine aminopeptidase from Bos taurus has showed the 125th amino acid position to be the
preference site of Cry1Ac protein. The structures were compared with each other and it showed 5% of similarity. The cross affinity
of this toxin that have confirmed the earlier reports of ill effects of Bt cotton consumed by cattle. 相似文献
246.
Rajeswaran Srinath Somasundaram Thirugnanasambandan Somasundaram Dewangan Naresh Kumar Moorthy Rajesh Kannan Kandasamy Saravanan Vilwanathan Ravikumar 《Biological trace element research》2020,194(1):273-283
Biological Trace Element Research - A simple, eco-friendly, green routine co-precipitation method was experimented to synthesize iron nanoparticles (Fe-NPs) using the cell-free supernatant of... 相似文献
247.
Achiraman S Archunan G Sankarganesh D Rajagopal T Rengarajan RL Kokilavani P Kamalakkannan S Kannan S 《Zoological science》2011,28(8):600-605
Species-specific chemical signals released through urine, sweat, saliva and feces are involved in communication between animals. Urinary biochemical constituents along with pheromones may contribute to variation across reproductive cycles and facilitate to estrus detection. Hence, the present study was designed to analyze such biochemical profiles, such as proteins, carbohydrates, lipids, fatty acids, in response with steroid hormones such as estradiol and progesterone. The experimental groups were normal, prepubertal, ovariectomized, and ovariectomized with estrogentreated female mice. In normal mice, the protein and lipid concentrations in urine were significantly higher in proestrus and estrus phases and the quantity of fatty acids was also comparatively higher in estrus. Furthermore, certain fatty acids, namely tridecanoic, palmitic and oleic acids, were present during proestrus and estrus phases, but were exclusively absent in ovariectomized mice. However, the carbohydrate level was equally maintained throughout the four phases of estrous cycle. For successful communication, higher concentrations of protein and specific fatty acids in estrus are directly involved. The significant increase in estradiol at estrus and progesterone at metestrus seems to be of greater importance in the expression pattern of biochemical constituents and may play a notable role in estrous cycle regulation. Thus, we conclude that the variations observed in the concentration of the biochemical constituents depend on the phase of the reproductive cycle as well as hormonal status of animals. The appearance of protein and specific fatty acids during estrus phase raises the possibility to use these as a urinary indicators for estrus detection. 相似文献
248.
Achiraman S Archunan G Abirami B Kokilavani P Suriyakalaa U SankarGanesh D Kamalakkannan S Kannan S Habara Y Sankar R 《Theriogenology》2011,76(9):1676-1683
Squalene in the rat clitoral gland is reported to be semi-volatile and may serve as a chemo-signal. The objective was to determine squalene concentrations in the clitoral gland throughout the reproductive cycle. Clitoral glands were extracted with dichloromethane; 23 compounds were identified with Gas Chromatography linked Mass Spectrometry (GC-MS). Since squalene concentrations were significantly higher during proestrus and estrus, and remarkably reduced during metestrus and diestrus, we inferred that it could be an ovulation-indicating chemosignal in the female rat, acting as a scent mark for the male. This hypothesis was tested by investigating its efficacy to attract males, including studying the role of the olfactory-vomeronasal system of the male in perceiving squalene. For detection of squalene, males used their conventional olfactory system when at a distance from the female, whereas the vomeronasal organ was used when they were in close proximity to the female. We concluded that squalene was a female-specific chemosignal that attracted males, and furthermore, that the olfactory-vomeronasal system had an important role in the perception of squalene. 相似文献
249.
The term epigenetics is defined as inheritable changes that influence the outcome of a phenotype without changes in the genome. Epigenetics is based upon DNA methylation and posttranslational histone modifications. While there is much known about reversible acetylation as a posttranslational modification, research on reversible histone methylation is still emerging, especially with regard to drug discovery. As aberrant epigenetic modifications have been linked to many diseases, inhibitors of histone modifying enzymes are very much in demand. This article will summarize the progress on small molecule epigenetic inhibitors identified by structure- and computer-based approaches. 相似文献
250.
Neuropeptide W (NPW) is a novel hypothalamic peptide that activates the orphan G protein-coupled receptors, GPR7 and GPR8. Two endogenous molecular forms of NPW that consist of 23- and 30-amino acid residues were identified. Intracerebroventricular (i.c.v.) administration of NPW is known to suppress spontaneous-feeding at dark-phase and fasting-induced food intake and to decrease body weight and plasma growth hormone and to increase prolactin and corticosterone; however, little is known about its effect on other physiological functions. We examined the effects of i.c.v. administration of NPW30 (0.3 and 3 nmol) on the mean arterial pressure (MAP), heart rate (HR), and plasma norepinephrine and epinephrine in conscious rats. NPW30 (3 nmol) provoked increases in MAP (85.12+/-3.16 to 106.26+/-2.66 mm Hg) and HR (305.75+/-13.76 to 428.45+/-26.82 beats/min) and plasma norepinephrine (138.1+/-18.1 to 297.2+/-25.9 pg/ml) and epinephrine (194.6+/-21.4 to 274.6+/-22.7 pg/ml). Intravenously administered NPW30 (3 nmol) had no significant effects on MAP and HR. These results indicate that central NPW30 increases sympathetic nervous outflow and affects cardiovascular function. 相似文献