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131.
In the present study the whole bacterial community structure of Tapovan hot spring soil located in the state of Uttarakhand, India was analysed through next generation sequencing. The hot spring soil is slightly alkaline in nature with abundance of sulphur. The spring soil was rich in various metallic and non-metallic elements required for bacterial survival. The community was found to comprise of 14 bacterial phyla with representation of members belonging to Firmicutes, Proteobacteria, Thermi, Bacteroidetes, Aquificae, Actinobacteria, chloroflexi, TM7, Fusobacteria etc. At the genus level Bacillus, Pseudomonas, Symbiobacterium, Thermus, Geobacillus, Anoxybacillus were found in abundance as compared to other genera like Flavobacterium, Ureibacillus, Clostridium, Meiothermus, Acinetobacter, Desulfotomaculum and Rheinheimera. 相似文献
132.
Chronic manganese (Mn) exposure in rodents, non-human primates and humans has been linked to Parkinson's disease like condition known as Manganism. Mn being a cofactor for many enzymes in brain has been known to be accumulated in various regions differentially and thus exert toxic effect upon chronic overexposure. In present study, neuropathology of Manganism was investigated by evaluating regional neuronal and astroglial metabolism in mice under chronic Mn exposure. Male C57BL6 mice were treated with MnCl(2) (25 mg/kg, i.p.) for 21 days. Cerebral metabolism was studied by co-infusing [U-(13)C(6)]glucose and [2-(13)C]acetate, and monitoring (13)C labeling of amino acids in brain tissue extract using (1)H-[(13)C] and (13)C-[(1)H]-NMR spectroscopy. Glutamate, choline, N-acetyl aspartate and myo-inositol were found to be reduced in thalamus and hypothalamus indicating a loss in neuronal and astroglial cells due to Mn neurotoxicity. Reduced labeling of Glu(C4) from [U-(13)C(6)]glucose and [2-(13)C]acetate indicates an impairment of glucose oxidation by glutamatergic neurons and glutamate-glutamine neurotransmitter cycle in cortex, striatum, thalamus-hypothalamus and olfactory bulb with chronic Mn exposure. Additionally, reduced labeling of Gln(C4) from [2-(13)C]acetate indicates a decrease in acetate oxidation by astroglia in the same regions. However, GABAergic function was alleviated only in thalamus-hypothalamus. Our findings indicate that chronic Mn impairs excitatory (glutamatergic) function in the majority of regions of brain while inhibitory (GABAergic) activity is perturbed only in basal ganglia. 相似文献
133.
134.
Ravindran R Juliet S Sunil AR Ajith Kumar KG Nair SN Amithamol KK Bandyopadhyay A Rawat AK Ghosh S 《Experimental & applied acarology》2012,56(1):69-74
Using adult immersion test, the acaricidal activity of ethanolic extracts of leaves of Cassia alata L. was studied against Rhipicephalus (Boophilus) annulatus. The efficacy was assessed by measuring per cent adult mortality, inhibition of fecundity and hatching rate. The ethanolic
extract of C. alata produced a concentration dependant increase in the adult tick mortality. The highest mortality (45.8%) and inhibition of
fecundity (10.9%) were observed at the highest concentration tested (100 mg/ml). The plant extract did not affect egg hatchability. 相似文献
135.
Md. Ashaduzzaman Siddikee Puneet S. Chauhan Tongmin Sa 《Journal of Plant Growth Regulation》2012,31(2):265-272
The present study was carried out to understand the mechanism of salt stress amelioration in red pepper plants by inoculation
of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase-producing halotolerant bacteria. In general, ethylene production,
ACC concentration, ACC synthase (ACS), and ACC oxidase (ACO) enzyme activities increased with increasing levels of salt stress.
Treatment with halotolerant bacteria reduced ethylene production by 47–64%, ACC concentration by 47–55% and ACO activity by
18–19% in salt-stressed (150 mmol NaCl) red pepper seedlings compared to uninoculated controls. ACS activity was lower in
red pepper seedlings treated with Bacillus aryabhattai RS341 but higher in seedlings treated with Brevibacterium epidermidis RS15 (44%) and Micrococcus yunnanensis RS222 (23%) under salt-stressed conditions as compared to uninoculated controls. A significant increase was recorded in red
pepper plant growth under salt stress when treated with ACC deaminase-producing halotolerant bacteria as compared to uninoculated
controls. The results of this study collectively suggest that salt stress enhanced ethylene production by increasing enzyme
activities of the ethylene biosynthetic pathway. Inoculation with ACC deaminase-producing halotolerant bacteria plays an important
role in ethylene metabolism, particularly by reducing the ACC concentration, although a direct effect on reducing ACO activity
was also observed. It is suggested that growth promotion in inoculated red pepper plants under inhibitory levels of salt stress
is due to ACC deaminase activity present in the halotolerant bacteria. 相似文献
136.
Several proteins with limited cell type distribution have been shown to bind lactoferrin. However, except in the case of hepatic and intestinal cells, these have not been definitively identified and characterized. Here we report that the multifunctional glycolytic protein glyceraldehyde-3-phosphate dehydrogenase (GAPDH) functions as a novel receptor for lactoferrin (Lf) in macrophages. GAPDH is a well-known moonlighting protein, and previous work from our laboratory has indicated its localization on macrophage cell surfaces, wherein it functions as a transferrin (Tf) receptor. The K(D) value for GAPDH-lactoferrin interaction was determined to be 43.8 nmol/L. Utilizing co-immunoprecipitation, immunoflorescence, and immunogold labelling electron microscopy we could demonstrate the trafficking of lactoferrin to the endosomal compartment along with GAPDH. We also found that upon iron depletion the binding of lactoferrin to macrophage cell surface is enhanced. This correlated with an increased expression of surface GAPDH, while other known lactoferrin receptors CD14 and lipoprotein receptor-related protein (LRP) were found to remain unaltered in expression levels. This suggests that upon iron depletion, cells prefer to use GAPDH to acquire lactoferrin. As GAPDH is an ubiquitously expressed molecule, its function as a receptor for lactoferrin may not be limited to macrophages. 相似文献
137.
138.
Sanjay Mishra Surya Prakash Dwivedi Neeraja Dwivedi Ajay Kumar Anil Rawat Yasushi Kamisaka 《Bioinformation》2009,3(9):394-398
Acyl CoA diacylglycerol acyltransferase (DGAT, EC 2.3.120) is recognized as a key player of cellular diacylglycerol
metabolism. It catalyzes the terminal, yet the committed step in triacylglycerol synthesis using diacylglycerol and fatty acyl CoA
as substrates. The protein sequence of diacylglycerol acyltransferse (DGAT) Type 2B in Moretierella ramanniana var.
angulispora (Protein_ID = ) was retrieved from GenBank. However, a structure is not yet available for this
sequence. The 3D structure of DGAT Type 2B was modeled using a template structure (PDB ID: 1K30) obtained from Protein
databank (PDB) identified by searching with position specific iterative BLAST (PSI-BLAST). The template (PDB ID: 1K30)
describes the structure of DGAT from Cucurbita moschata. Modeling was performed using Modeller 9v2 and protein model is
hence generated. The DGAT type 2B protein model was subsequently docked with six inhibitors (sphingosine; trifluoroperazine;
phosphatidic acid; lysophospatidylserine; KCl; 1, 2-diolein) using AutoDock (a molecular docking program). The binding of
inhibitors to the protein model of DGAT type 2B is discussed. AAK84180.1相似文献
139.
Preeti Rawat Sanjeev Kumar Deepak Pental Pradeep Kumar Burma 《Journal of biosciences》2009,34(2):199-202
Agrobacterium strains harbour insertion sequences, which are known to transpose into genomes as well as into Ti plasmids. In this study
we report the inactivation of a transgene due to transposition of the A. tumefaciens insertion sequence IS136. The transposition was discovered following transformation of plant tissues, although the fidelity
of the binary vector was confirmed following transformation into Agrobacterium. Such transpositions are rare but can occur and it is thus important to check the fidelity of the binary vector at different
times of Agrobacterium growth in order to avoid failure in achieving transgene expression. 相似文献
140.
Puppione DL Donna LD Laganowsky AD Bassilian S Souda P Ryder OA Whitelegge JP 《Comparative biochemistry and physiology. Part D, Genomics & proteomics》2009,4(4):305-309
The two major apolipoproteins associated with human and chimpanzee (Pan troglodytes) high density lipoproteins (HDL) are apoA-I and dimeric apoA-II. Although humans are closely related to great apes, apolipoprotein data do not exist for bonobos (Pan paniscus), western lowland gorillas (Gorilla gorilla gorilla) and the Sumatran orangutans (Pongo abelii). In the absence of any data, other great apes simply have been assumed to have dimeric apoA-II while other primates and most other mammals have been shown to have monomeric apoA-II. Using mass spectrometry, we have measured the molecular masses of apoA-I and apoA-II associated with the HDL of these great apes. Each was observed to have dimeric apoA-II. Being phylogenetically related, one would anticipate these apolipoproteins having a high percentage of invariant sequences when compared with human apolipoproteins. However, the orangutan, which diverged from the human lineage between 16 and 21 million years ago, had an apoA-II with the lowest monomeric mass, 8031.3 Da and the highest apoA-I value, 28,311.7 Da, currently reported for various mammals. Interestingly, the gorilla that diverged from the lineage leading to the human–chimpanzee branch after the orangutan had almost identical mass values to those reported for human apoA-I and apoA-II. But chimpanzee and the bonobo that diverged more recently had identical apoA-II mass values that were slightly larger than reported for the human apolipoprotein. The chimpanzee A-I mass values were very close to those of humans; however, the bonobo had values intermediate to the molecular masses of orangutan and the other great apes. With the already existing genomic data for chimpanzee and the recent entries for the orangutan and gorilla, we were able to demonstrate a close agreement between our mass spectral data and the calculated molecular weights determined from the predicted primary sequences of the respective apolipoproteins. Post-translational modification of these apolipoproteins, involving truncation and oxidation of methionine, are also reported. 相似文献