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83.
Lactic acid bacteria (LAB) are possessing ability to synthesize antimicrobial compounds (like bacteriocin) during their growth.
In this regard, novel bacteriocin compound secreting capability of LAB isolated from Tulum Cheese in Turkey was demonstrated.
The synthesized bacteriocin was purified by ammonium sulphate precipitation, dialysis and gel filtration. The molecular weight
(≈3.4 kDa) of obtained bacteriocin was confirmed by SDS-PAGE, which revealed single peptide band. Molecular identification
of LAB strain isolated from Tulum Cheese was conducted using 16S rDNA gene sequencing as Lactococcus lactis ssp. lactis LL171. The amino acid sequences (KKIDTRTGKTMEKTEKKIELSLKNMKTAT) of the bacteriocin from Lactococcus lactis ssp. lactis LL171 was found unique and novel than reported bacteriocins. Further, the bacteriocin was possessed the thermostable property
and active at wide range of pH values from 1 to 11. Thus, bacteriocin reported in this study has the potential applications
property as food preservative agent. 相似文献
84.
Elicitation is one of the few strategies that find commercial application in the enhancement of secondary metabolite production
from plants as well as cell culture systems. Due to their immense medicinal value, production of saponins in suspension cultures
has been attempted by many researchers. Gymnema sylvestre is a rich source of gymnemic acids (saponins) that find application in the treatment of diabetes. The present study is an
attempt to evaluate the effect of various metal salts (cadmium chloride, mercuric chloride, silver nitrate, cupric chloride,
cobaltous chloride and calcium chloride) in eliciting the response from G. sylvestre suspension cultures. The maximum gymnemic acid production in the suspensions was achieved on day 12 of culture, though the
maximum biomass was obtained on day 16. Among the different salts, CdCl2 gave maximum response (59.97 mg/gDCW) at 2 mM concentration after a 24 h time period, while, AgNO3 gave the least response (18.35 mg/gDCW) on incubation of 48 h at 1 mM concentration, in terms of gymnemic acid accumulation.
The accumulation of gymnemic acid was found to be dependent on treatment time and concentration of the elicitor. The enhanced
gymnemic acid production shown by the suspensions in response to the metal salts indicates their role in evoking the plant
defense mechanisms. These elicitation studies help in providing a platform for improved commercial supply of bioactive gymnemic
acids. 相似文献
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86.
U Sarma A Sareen M Maiti V Kamat R Sudan S Pahari N Srivastava S Roy S Sinha I Ghosh AG Chande R Mukhopadhyaya B Saha 《PloS one》2012,7(7):e39898
Depending on the strength of signal dose, CD40 receptor (CD40) controls ERK-1/2 and p38MAPK activation. At low signal dose, ERK-1/2 is maximally phosphorylated but p38MAPK is minimally phosphorylated; as the signal dose increases, ERK-1/2 phosphorylation is reduced whereas p38MAPK phosphorylation is reciprocally enhanced. The mechanism of reciprocal activation of these two MAPKs remains un-elucidated. Here, our computational model, coupled to experimental perturbations, shows that the observed reciprocity is a system-level behavior of an assembly of kinases arranged in two modules. Experimental perturbations with kinase inhibitors suggest that a minimum of two trans-modular negative feedback loops are required to reproduce the experimentally observed reciprocity. The bi-modular architecture of the signaling pathways endows the system with an inherent plasticity which is further expressed in the skewing of the CD40-induced productions of IL-10 and IL-12, the respective anti-inflammatory and pro-inflammatory cytokines. Targeting the plasticity of CD40 signaling significantly reduces Leishmania major infection in a susceptible mouse strain. Thus, for the first time, using CD40 signaling as a model, we show how a bi-modular assembly of kinases imposes reciprocity to a receptor signaling. The findings unravel that the signalling plasticity is inherent to a reciprocal system and that the principle can be used for designing a therapy. 相似文献
87.
Federico Vaggi James Dodgson Archana Bajpai Anatole Chessel Ferenc Jordán Masamitsu Sato Rafael Edgardo Carazo-Salas Attila Csikász-Nagy 《PLoS computational biology》2012,8(10)
The study of gene and protein interaction networks has improved our understanding of the multiple, systemic levels of regulation found in eukaryotic and prokaryotic organisms. Here we carry out a large-scale analysis of the protein-protein interaction (PPI) network of fission yeast (Schizosaccharomyces pombe) and establish a method to identify ‘linker’ proteins that bridge diverse cellular processes - integrating Gene Ontology and PPI data with network theory measures. We test the method on a highly characterized subset of the genome consisting of proteins controlling the cell cycle, cell polarity and cytokinesis and identify proteins likely to play a key role in controlling the temporal changes in the localization of the polarity machinery. Experimental inspection of one such factor, the polarity-regulating RNB protein Sts5, confirms the prediction that it has a cell cycle dependent regulation. Detailed bibliographic inspection of other predicted ‘linkers’ also confirms the predictive power of the method. As the method is robust to network perturbations and can successfully predict linker proteins, it provides a powerful tool to study the interplay between different cellular processes. 相似文献
88.
Suchi Srivastava Vasvi Chaudhry Aradhana Mishra Puneet Singh Chauhan Ateequr Rehman Archana Yadav Narendra Tuteja Chandra Shekhar Nautiyal 《Plant signaling & behavior》2012,7(2):235-245
Plant growth promotion is a multigenic process under the influence of many factors; therefore an understanding of these processes and the functions regulated may have profound implications. Present study reports microarray analysis of Arabidopsis thaliana plants inoculated with Pseudomonas putida MTCC5279 (MTCC5279) which resulted in significant increase in growth traits as compared with non-inoculated control. The gene expression changes, represented by oligonucleotide array (24652 genes) have been studied to gain insight into MTCC5279 assisted plant growth promotion in Arabidopsis thaliana. MTCC5279 induced upregulated Arabidopsis thaliana genes were found to be involved in maintenance of genome integrity (At5g20850), growth hormone (At3g23890 and At4g36110), amino acid synthesis (At5g63890), abcissic acid (ABA) signaling and ethylene suppression (At2g29090, At5g17850), Ca+2 dependent signaling (At3g57530) and induction of induced systemic resistance (At2g46370, At2g44840). The genes At3g32920 and At2g15890 which are suggested to act early in petal, stamen and embryonic development are among the downregulated genes. We report for the first time MTCC5279 assisted repression of At3g32920, a putative DNA repair protein involved in recombination and DNA strand transfer in a process of rapid meiotic and mitotic division. 相似文献
89.
Involvement of secretory and endosomal compartments in presentation of an exogenous self-glycolipid to type II NKT cells 总被引:1,自引:0,他引:1
Roy KC Maricic I Khurana A Smith TR Halder RC Kumar V 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(5):2942-2950
Natural Killer T (NKT) cells recognize both self and foreign lipid Ags presented by CD1 molecules. Although presentation of the marine sponge-derived lipid alphaGalCer to type I NKT cells has been well studied, little is known about self-glycolipid presentation to either type I or type II NKT cells. Here we have investigated presentation of the self-glycolipid sulfatide to a type II NKT cell that specifically recognizes a single species of sulfatide, namely lyso-sulfatide but not other sulfatides containing additional acyl chains. In comparison to other sulfatides or alphaGalCer, lyso-sulfatide binds with lower affinity to CD1d. Although plate-bound CD1d is inefficient in presenting lyso-sulfatide at neutral pH, it is efficiently presented at acidic pH and in the presence of saposin C. The lysosomal trafficking of mCD1d is required for alphaGalCer presentation to type I NKT cells, it is not important for presentation of lyso-sulfatide to type II NKT cells. Consistently, APCs deficient in a lysosomal lipid-transfer protein effectively present lyso-sulfatide. Presentation of lyso-sulfatide is inhibited in the presence of primaquine, concanamycin A, monensin, cycloheximide, and an inhibitor of microsomal triglyceride transfer protein but remains unchanged following treatment with brefeldin A. Wortmannin-mediated inhibition of lipid presentation indicates an important role for the PI-3kinase in mCD1d trafficking. Our data collectively suggest that weak CD1d-binding self-glycolipid ligands such as lyso-sulfatide can be presented via the secretory and endosomal compartments. Thus this study provides important insights into the exogenous self-glycolipid presentation to CD1d-restricted T cells. 相似文献
90.
Soumyakanta Sahoo Shashikant Srivastava Archana Ayyagari 《World journal of microbiology & biotechnology》2008,24(9):1977-1979
Haemophilus influenzae type b meningitis has been reported predominantly among infants who have not completed the primary immunization series, whereas
infection by capsular f has been reported mostly in patients with significant underlying diseases. The present study analyses
H. influenzae type b & f infection among 25 unvaccinated patients with respiratory tract infections and symptoms of meningitis by PCR.
5/7 isolates from CSF sample were capsular type b; whereas capsular type f was detected in 2/10 and 5/8 isolates from throat
swab and sputum samples, respectively. Rest 13 strains were negative for both the capsular types. To conclude, in India where
H. influenzae type b conjugate vaccine is not included in national immunization program, individuals with respiratory tract infections
and meningitis are at a greater risk of developing infection with H. influenzae type b strains along with other capsular types and non-capsular types. 相似文献