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41.
Rakesh Ranjan Ramesh J. Pandit Srinivas M. Duggirala Chaitanya G. Joshi Shradhdha Sharma Niteen V. Patil 《Annals of microbiology》2018,68(2):103-110
The lactic acid bacterium Pediococcus acidilactici has recently been reported to help in treating constipation, diarrhea, relieving stress, and enhancing growth rate and immune response in humans, birds, fishes, and small animals. In the present study, we sequenced and analyzed the whole genome of P. acidilactici NRCC1, a novel isolate from rumen fluid of dromedary camel (Camelus dromedarius). The genome of P. acidilactici NRCC1 was assembled into 60 contigs, comprising 1,785,679 bp and 42.5% GC content. The 1705 CDS were predicted and annotated using the RAST server. The genome encodes numerous enzymes for utilization of different carbohydrates. It also harbors genes for antibiotic biosynthesis and many others which might confer probiotic properties. The comparative genome analysis with P. acidilactici DSM 20284 revealed some unique features in P. acidilactici NRCC1. Thus, the genome sequencing of P. acidilactici NRCC1 has opened up new horizons for further research in animal probiotics and feed supplements. 相似文献
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44.
Maria Ermakova Russell Woodford Zachary Taylor Robert T. Furbank Srinivas Belide Susanne von Caemmerer 《Plant biotechnology journal》2023,21(6):1206-1216
Sorghum is one of the most important crops providing food and feed in many of the world's harsher environments. Sorghum utilizes the C4 pathway of photosynthesis in which a biochemical carbon-concentrating mechanism results in high CO2 assimilation rates. Overexpressing the Rieske FeS subunit of the Cytochrome b6f complex was previously shown to increase the rate of photosynthetic electron transport and stimulate CO2 assimilation in the model C4 plant Setaria viridis. To test whether productivity of C4 crops could be improved by Rieske overexpression, we created transgenic Sorghum bicolor Tx430 plants with increased Rieske content. The transgenic plants showed no marked changes in abundances of other photosynthetic proteins or chlorophyll content. The steady-state rates of electron transport and CO2 assimilation did not differ between the plants with increased Rieske abundance and control plants, suggesting that Cytochrome b6f is not the only factor limiting electron transport in sorghum at high light and high CO2. However, faster responses of non-photochemical quenching as well as an elevated quantum yield of Photosystem II and an increased CO2 assimilation rate were observed from the plants overexpressing Rieske during the photosynthetic induction, a process of activation of photosynthesis upon the dark–light transition. As a consequence, sorghum with increased Rieske content produced more biomass and grain when grown in glasshouse conditions. Our results indicate that increasing Rieske content has potential to boost productivity of sorghum and other C4 crops by improving the efficiency of light utilization and conversion to biomass through the faster induction of photosynthesis. 相似文献
45.
Muscular dystrophies (MDs) such as Duchenne muscular dystrophy (DMD), sarcoglycanopathy (Sgpy) and dysferlinopathy (Dysfy)
are recessive genetic neuromuscular diseases that display muscle degeneration. Although these MDs have comparable endpoints
of muscle pathology, the onset, severity and the course of these diseases are diverse. Different mechanisms downstream of
genetic mutations might underlie the disparity in these pathologies. We surmised that oxidative damage and altered antioxidant
function might contribute to these differences. The oxidant and antioxidant markers in the muscle biopsies from patients with
DMD (n = 15), Sgpy (n = 15) and Dysfy (n = 15) were compared to controls (n = 10). Protein oxidation and lipid peroxidation was evident in all MDs and correlated with the severity of pathology, with
DMD, the most severe dystrophic condition showing maximum damage, followed by Sgpy and Dysfy. Oxidative damage in DMD and
Sgpy was attributed to the depletion of glutathione (GSH) and lowered antioxidant activities while loss of GSH peroxidase
and GSH-S-transferase activities was observed in Dysfy. Lower GSH level in DMD was due to lowered activity of gamma-glutamyl
cysteine ligase, the rate limiting enzyme in GSH synthesis. Similar analysis in cardiotoxin (CTX) mouse model of MD showed
that the dystrophic muscle pathology correlated with GSH depletion and lipid peroxidation. Depletion of GSH prior to CTX exposure
in C2C12 myoblasts exacerbated oxidative damage and myotoxicity. We deduce that the pro and anti-oxidant mechanisms could
be correlated to the severity of MD and might influence the dystrophic pathology to a different extent in various MDs. On
a therapeutic note, this could help in evolving novel therapies that offer myoprotection in MD. 相似文献
46.
Tian W Han X Yan M Xu Y Duggineni S Lin N Luo G Li YM Han X Huang Z An J 《Biochemistry》2012,51(2):724-731
Overactivation or overexpression of β-catenin in the Wnt (wingless) signaling pathway plays an important role in tumorigenesis. Interaction of β-catenin with T-cell factor (Tcf) DNA binding proteins is a key step in the activation of the proliferative genes in response to upstream signals of this Wnt/β-catenin pathway. Recently, we identified a new small molecule inhibitor, named BC21 (C(32)H(36)Cl(2)Cu(2)N(2)O(2)), which effectively inhibits the binding of β-catenin with Tcf4-derived peptide and suppresses β-catenin/Tcf4 driven reporter gene activity. This inhibitor decreases the viability of β-catenin overexpressing HCT116 colon cancer cells that harbor the β-catenin mutation, and more significantly, it inhibits the clonogenic activity of these cells. Down-regulation of c-Myc and cyclin D1 expression, the two important effectors of the Wnt/β-catenin signaling, is confirmed by treating HCT116 cells with BC21. This compound represents a new and modifiable potential anticancer candidate that targets β-catenin/Tcf-4 interaction. 相似文献
47.
This communication reports gelation of lambda-carrageenan, for the first time, in the presence of trivalent iron ions. Kappa-, iota- and lambda-carrageenans are sulfated polysaccharides used extensively in food, pharmaceutical and medical applications. Kappa- and iota-carrageenans show gelation in the presence of mono- and di-valent ions, but lambda-carrageenan yields only viscous solutions. Our results show that gelation in lambda-carrageenan indeed is possible, but with trivalent ions. X-ray fiber diffraction patterns of iron (III)-lambda-carrageenan are characteristic of highly oriented and polycrystalline fibers containing well resolved Bragg reflections. The elastic modulus (G′) of the product is far greater than the loss modulus (G″) indicating the thermal stability of lambda-carrageenan in the presence of iron (III) ions. This novel finding has potential to expand lambda-carrageenan's current utility beyond a viscosifying agent. 相似文献
48.
Balaji KN Goyal G Narayana Y Srinivas M Chaturvedi R Mohammad S 《Microbes and infection / Institut Pasteur》2007,9(3):271-281
Ectopic expression of the Mycobacterium tuberculosis PE-family gene Rv1818c, triggers apoptosis in the mammalian Jurkat T cells, which is blocked by anti-apoptotic protein Bcl-2. Although complete overlap is not observed, a considerable proportion of cellular pools of ectopically expressed Rv1818c localizes to mitochondria. However, recombinant Rv1818c does not trigger release of cytochrome c from isolated mitochondria even though Rv1818c protein induced apoptosis of Jurkat T cells. Apoptosis induced by Rv1818c is blocked by the broad-spectrum caspase inhibitory peptide zVAD-FMK. Unexpectedly, Rv1818c-induced apoptosis is not blocked in a Jurkat sub-clone deficient for caspase-8 (JI 9.2) or in cells where caspase-9 function is inhibited or expression of caspase-9 reduced by siRNA, arguing against a central role for these caspases in Rv1818c-induced apoptotic signaling. Depleting cellular pools of the mitochondrial protein Smac/DIABLO substantially reduces apoptosis consistent with mitochondrial involvement in this death pathway. We present evidence that Rv1818c-induced apoptosis is blocked by the co-transfection of an endogenous inhibitor of caspase activation, XIAP in T cells. Additionally, Rv1818c is released into extracellular environment via exosomes secreted by M. tuberculosis infected BM-DC's and macrophages. Furthermore, the extracellular Rv1818c protein can be detected in T cells co-cultured with infected BM-DC's. Taken together, these data suggest that Rv1818c-induced apoptotic signaling is likely regulated in part by the Smac-dependent activation of caspases in T cells. 相似文献
49.
Nupur Bhumika Vaidya Naga Radha Srinivas Tanuku Anil Kumar Pinnaka 《Antonie van Leeuwenhoek》2013,103(2):347-355
A novel marine, Gram-negative, rod-shaped bacterium, designated strain N9T, was isolated from a water sample of the sea shore at Visakhapatnam, Andhra Pradesh (India). Strain N9T was found to be positive for oxidase and catalase activities. The fatty acids were found to be dominated by C16:0, C18:1 ω7c and summed in feature 3 (C16:1 ω7c and/or C16:1 ω6c). Strain N9T was determined to contain Q-10 as the major respiratory quinone and phosphatidylethanolamine, phosphatidylglycerol, two aminophospholipids, two phospholipids and four unidentified lipids as polar lipids. The DNA G+C content of the strain N9T was found to be 63 mol%. 16S rRNA gene sequence analysis indicated that Rhodobacter sphaeroides, Rhodobacter johrii, Pseudorhodobacter ferrugineus, Rhodobacter azotoformans, Rhodobacter ovatus and Pseudorhodobacter aquimaris were the nearest phylogenetic neighbours, with pair-wise sequence similarities of 95.43, 95.36, 94.24, 95.31, 95.60 and 94.74 %, respectively. Phylogenetic analysis showed that strain N9T formed a distinct branch within the family Rhodobacteraceae and clustered with the clade comprising species of the genus Pseudorhodobacter, together with species of the genera Roseicitreum, Roseinatronobacter, Roseibaca and Rhodobaca. Species of the genus Pseudorhodobacter are phylogenetically close with a 16S rRNA gene sequence dissimilarity of 5.9–7.3 % (92.7–94.1 % similarity). Based on the above-mentioned phenotypic characteristics and on phylogenetic inference, strain N9T is proposed as a representative of a new genus and a novel species of the family Rhodobacteraceae as Albirhodobacter marinus gen. nov., sp. nov. The type strain of Albirhodobacter marinus is N9 (= MTCC 11277T = JCM 17680T). 相似文献
50.
Sudeep Chenna Narendra Jaya Prakash Chalise Mattias Magnusson Srinivas Uppugunduri 《PloS one》2015,10(10)