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21.
Biswajit Brahma Sushil Kumar Bidhan Chandra De Purusottam Mishra Mahesh Chandra Patra Deepak Gaur Meenu Chopra Devika Gautam Sourav Mahanty Hrudananda Malik Dhruba Malakar Tirtha Kumar Datta Sachinandan De 《PloS one》2015,10(3)
Nucleotide binding and oligomerization domain (NOD)-like receptors (NLRs) are innate immune receptors that recognize bacterial cell wall components and initiate host immune response. Structure and function of NLRs have been well studied in human and mice, but little information exists on genetic composition and role of these receptors in innate immune system of water buffalo—a species known for its exceptional disease resistance. Here, a comparative study on the functional domains of NOD1 and NOD2 was performed across different species. The NOD mediated in-vitro cellular responses were studied in buffalo peripheral blood mononuclear cells, resident macrophages, mammary epithelial, and fibroblast cells. Buffalo NOD1 (buNOD1) and buNOD2 showed conserved domain architectures as found in other mammals. The domains of buNOD1 and buNOD2 showed analogy in secondary and tertiary conformations. Constitutive expressions of NODs were ubiquitous in different tissues. Following treatment with NOD agonists, peripheral lymphocytes showed an IFN-γ response along-with production of pro-inflammatory cytokines. Alveolar macrophages and mammary epithelial cells showed NOD mediated in-vitro immune response through NF-κB dependent pathway. Fibroblasts showed pro-inflammatory cytokine response following agonist treatment. Our study demonstrates that both immune and non-immune cells could generate NOD-mediated responses to pathogens though the type and magnitude of response depend on the cell types. The structural basis of ligand recognition by buffalo NODs and knowledge of immune response by different cell types could be useful for development of non-infective innate immune modulators and next generation anti-inflammatory compounds. 相似文献
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Introgression and functional expression of either the PcINO1 (l-myo-inositol 1-phosphate synthase or MIPS coding gene from the wild halophytic rice, Porteresia coarctata) or McIMTI (inositol methyl transferase, IMTI coding gene from common ice plant Mesembryanthemum crystallinum) has earlier been shown to confer salt tolerance to transgenic tobacco plants (Sheveleva et al., Plant Physiol 115:1211–1219, 1997; Majee et al., J Biol Chem 279:28539–28552, 2004). In this communication, we show that transgenic tobacco plants co-expressing PcINO1 and McIMT1 gene either in cytosol or in chloroplasts accumulate higher amount of total inositol (free and methyl inositol) compared to non-transgenic plants. These transgenic plants were more competent in terms of growth potential and photosynthetic activity and were less prone to oxidative stress under salt stress. A positive correlation between the elevated level of total inositol and methylated inositol and the capability of the double transgenic plants to withstand a higher degree of salt stress compared to the plants expressing either PcINO1 or McIMT1 alone is inferred. 相似文献
25.
The genome sequence of the cyanobacterium Synechocystis sp. PCC6803 revealed four Open reading frame (ORF) encoding putative inositol monophosphatase or inositol monophosphatase-like
proteins. One of the ORFs, sll1383, is ∼870 base pair long and has been assigned as a probable myo-inositol 1 (or 4) monophosphatase (IMPase; EC 3.1.3.25). IMPase is the second enzyme in the inositol biosynthesis pathway
and catalyses the conversion of L-myo-inositol 1-phosphate to free myo-inositol. The present work describes the functional assignment of ORF sll1383 as myo-inositol 1-phosphate phosphatase (IMPase) through molecular cloning, bacterial overexpression, purification and biochemical
characterization of the gene product. Affinity (K
m) of the recombinant protein for the substrate DL-myo-inositol 1-phosphate was found to be much higher (0.0034 ± 0.0003 mM) compared to IMPase(s) from other sources but in comparison
V
max (∼0.033 μmol Pi/min/mg protein) was low. Li+ was found to be an inhibitor (IC50 6.0 mM) of this enzyme, other monovalent metal ions (e.g. Na+, K+ NH4+) having no significant effect on the enzyme activity. Like other IMPase(s), the activity of this enzyme was found to be totally
Mg2+ dependent, which can be substituted partially by Mn2+. However, unlike other IMPase(s), the enzyme is optimally active at ∼42°C. To the best of our knowledge, sll1383 encoded
IMPase has the highest substrate affinity and specificity amongst the known examples from other prokaryotic sources. A possible
application of this recombinant protein in the enzymatic coupled assay of L-myo-inositol 1-phosphate synthase (MIPS) is discussed. 相似文献
26.
Schilders G Raijmakers R Malmegrim KC Vande Walle L Saelens X Vree Egberts W van Venrooij WJ Vandenabeele P Pruijn GJ 《Arthritis research & therapy》2007,9(1):R12
Recent studies have implicated the dying cell as a potential reservoir of modified autoantigens that might initiate and drive
systemic autoimmunity in susceptible hosts. A number of subunits of the exosome, a complex of 3'→5' exoribonucleases that
functions in a variety of cellular processes, are recognized by the so-called anti-PM/Scl autoantibodies, found predominantly
in patients suffering from an overlap syndrome of myositis and scleroderma. Here we show that one of these subunits, PM/Scl-75,
is cleaved during apoptosis. PM/Scl-75 cleavage is inhibited by several different caspase inhibitors. The analysis of PM/Scl-75
cleavage by recombinant caspase proteins shows that PM/Scl-75 is efficiently cleaved by caspase-1, to a smaller extent by
caspase-8, and relatively inefficiently by caspase-3 and caspase-7. Cleavage of the PM/Scl-75 protein occurs in the C-terminal
part of the protein at Asp369 (IILD369↓G), and at least a fraction of the resulting N-terminal fragments of PM/Scl-75 remains associated with the exosome. Finally,
the implications of PM/Scl-75 cleavage for exosome function and the generation of anti-PM/Scl-75 autoantibodies are discussed. 相似文献
27.
Ghosh Chiranjit Patra Debashis Bala Niranjan Majumder Indira Sepay Nayim Mukhopadhyay Prabuddha Das Sukhen Kundu Rita Drew Michael G. B. León Armando Rafael Ghosh Tapas Pradhan Manik 《Biometals》2022,35(3):499-517
BioMetals - A family of dioxidovanadium(V) complexes (1–4) of the type [Na(H2O)x]+[VVO2(HL1?4)]? (x?=?4, 4.5 and 7) where HL2? represents the dianionic form of... 相似文献
28.
Amritaj Patra Qianqian Zhang Li Lei Yan Su Martin Egli F. Peter Guengerich 《The Journal of biological chemistry》2015,290(13):8028-8038
The most common lesion in DNA is an abasic site resulting from glycolytic cleavage of a base. In a number of cellular studies, abasic sites preferentially code for dATP insertion (the “A rule”). In some cases frameshifts are also common. X-ray structures with abasic sites in oligonucleotides have been reported for several microbial and human DNA polymerases (pols), e.g. Dpo4, RB69, KlenTaq, yeast pol ι, human (h) pol ι, and human pol β. We reported previously that hpol η is a major pol involved in abasic site bypass (Choi, J.-Y., Lim, S., Kim, E. J., Jo, A., and Guengerich, F. P. (2010 J. Mol. Biol. 404, 34–44). hpol η inserted all four dNTPs in steady-state and pre-steady-state assays, preferentially inserting A and G. In LC-MS analysis of primer-template pairs, A and G were inserted but little C or T was inserted. Frameshifts were observed when an appropriate pyrimidine was positioned 5′ to the abasic site in the template. In x-ray structures of hpol η with a non-hydrolyzable analog of dATP or dGTP opposite an abasic site, H-bonding was observed between the phosphate 5′ to the abasic site and water H-bonded to N1 and N6 of A and N1 and O6 of G nucleoside triphosphate analogs, offering an explanation for what appears to be a “purine rule.” A structure was also obtained for an A inserted and bonded in the primer opposite the abasic site, but it did not pair with a 5′ T in the template. We conclude that hpol η, a major copying enzyme with abasic sites, follows a purine rule, which can also lead to frameshifts. The phenomenon can be explained with H-bonds. 相似文献
29.
Patra Falguni Tomar Sudhir Kumar Rajput Yudhishthir Singh Singh Rameshwar 《World journal of microbiology & biotechnology》2011,27(4):933-939
Mannitol is a naturally occurring low calorie sweetener, widely used in the food, pharmaceutical, medicine and chemical industries.
In this study mannitol producing strains of Leuconostoc spp. (210) were isolated from a wide array of sources such as raw milk, fermented milks, fermented cereal foods, fruits,
vegetables and sugar factory syrup. During initial screening, half of the population of these isolates (105) exhibited ability
to produce mannitol to a variable extent. Only 11.4% isolate produced mannitol yield of above 80% (when fructose used @ 50 g/l).
Cultural and environmental factors affecting growth and mannitol production were studied for four high mannitol producing
isolates. High mannitol production was favored by high temperature and high pH. Isolates had high osmotic tolerance as these
could use fructose concentration as high as 100 g/l in batch culture. Sequencing of 16S rRNA genes of the strains revealed
that Ln27, Ln104 and Ln206 were Leuconostoc mesenteroides and Ln92 was Leuconostoc fallax. 相似文献
30.
Chakravorty D Parameswaran S Dubey VK Patra S 《Extremophiles : life under extreme conditions》2011,15(1):89-103
Thermostable lipases are of high priority for industrial applications as they are endowed with the capability of carrying
out diversified reactions at elevated temperatures. Extremophiles are their potential source. Sequence and structure annotation
of thermostable lipases can elucidate evolution of lipases from their mesophilic counterparts with enhanced thermostability
hence better industrial potential. Sequence analysis highlighted the conserved residues in bacterial and fungal thermostable
lipases. Higher frequency of AXXXA motif and poly Ala residues in lid domain of thermostable Bacillus lipases were distinguishing characteristics. Comparison of amino acid composition among thermostable and mesostable lipases
brought into light the role of neutral, charged and aromatic amino acid residues in enhancement of thermostability. Structural
annotation of thermostable lipases with that of mesostable lipases revealed some striking features which are increment of
gamma turns in thermostable lipases; being first time reported in our paper, longer beta strands, lesser beta-branched residues
in helices, increase in charged-neutral hydrogen bonding pair, hydrophobic-hydrophobic contact and differences in the N-cap
and C-cap residues of the α helices. Conclusively, it can be stated that subtle changes in the arrangement of amino acid residues
in the tertiary structure of lipases contributes to enhanced thermostability. 相似文献