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231.
Aftab Ahamed Ajay Singh Owen P. Ward 《World journal of microbiology & biotechnology》2005,21(8-9):1577-1583
Summary While Aspergillus strains are also being considered as potential hosts for production of extracellular heterologous proteins, the proteases
produced by the host are highly problematic in that they typically modify and degrade the recombinant proteins. Culture-based
approaches for minimization of protease activity in culture supernatants of Aspergillus niger NRRL-3 included reduction or elimination of peptide nitrogen in the medium, preferential use of a defined salts medium rather
than a non-peptide nitrogen medium containing yeast-nitrogen base, supplementation of the medium with carboxymethylcellulose
and cultivation at pH 6.5 rather than 7.5. In general, increased proteolytic activity was observed after maximum biomass was
observed and biomass was declining suggesting the majority of protease activity was released by cell lysis. Carboxymethylcellulose
shifted mycelial morphology from pelleted to filamentous. Mycelium lysis in the centre of pellets, with resultant release
of intracellular proteases, would explain why filamentous cultures exhibited much lower proteolytic activity than pelleted
cultures. 相似文献
232.
Amod D. Kulkarni Viswanath Kiron Jan H. W. M. Rombout Monica F. Brinchmann Jorge M. O. Fernandes Naduvilamuriparampu S. Sudheer Bright I. S. Singh 《Proteomics》2014,14(13-14):1660-1673
White spot syndrome virus (WSSV) is a pathogen that causes considerable mortality of the farmed shrimp, Penaeus monodon. Candidate ‘vaccines’, WSSV envelope protein VP28 and formalin‐inactivated WSSV, can provide short‐lived protection against the virus. In this study, P. monodon was orally intubated with the aforementioned vaccine candidates, and protein expression in the gut of immunised shrimps was profiled. The alterations in protein profiles in shrimps infected orally with live‐WSSV were also examined. Seventeen of the identified proteins in the vaccine and WSSV‐intubated shrimps varied significantly compared to those in the control shrimps. These proteins, classified under exoskeletal, cytoskeletal, immune‐related, intracellular organelle part, intracellular calcium‐binding or energy metabolism, are thought to directly or indirectly affect shrimp's immunity. The changes in the expression levels of crustacyanin, serine proteases, myosin light chain, and ER protein 57 observed in orally vaccinated shrimp may probably be linked to immunoprotective responses. On the other hand, altered expression of proteins linked to exoskeleton, calcium regulation and energy metabolism in WSSV‐intubated shrimps is likely to symbolise disturbances in calcium homeostasis and energy metabolism. 相似文献
233.
Chang KH Multani PS Sun KH Vincent F de Pablo Y Ghosh S Gupta R Lee HP Lee HG Smith MA Shah K 《Molecular biology of the cell》2011,22(9):1452-1462
Nuclear fragmentation is a common feature in many neurodegenerative diseases, including Alzheimer's disease (AD). In this study, we show that nuclear lamina dispersion is an early and irreversible trigger for cell death initiated by deregulated Cdk5, rather than a consequence of apoptosis. Cyclin-dependent kinase 5 (Cdk5) activity is significantly increased in AD and contributes to all three hallmarks: neurotoxic amyloid-β (Aβ), neurofibrillary tangles (NFT), and extensive cell death. Using Aβ and glutamate as the neurotoxic stimuli, we show that deregulated Cdk5 induces nuclear lamina dispersion by direct phosphorylation of lamin A and lamin B1 in neuronal cells and primary cortical neurons. Phosphorylation-resistant mutants of lamins confer resistance to nuclear dispersion and cell death on neurotoxic stimulation, highlighting this as a major mechanism for neuronal death. Rapid alteration of lamin localization pattern and nuclear membrane change are further supported by in vivo data using an AD mouse model. After p25 induction, the pattern of lamin localization was significantly altered, preceding neuronal death, suggesting that it is an early pathological event in p25-inducible transgenic mice. Importantly, lamin dispersion is coupled with Cdk5 nuclear localization, which is highly neurotoxic. Inhibition of nuclear dispersion rescues neuronal cells from cell death, underscoring the significance of this event to Cdk5-mediated neurotoxicity. 相似文献
234.
Transport and Metabolism of Sucrose versus Hexoses in Relation to Growth in Etiolated Pea Stem 下载免费PDF全文
Sucrose, supplied to detached pea (Pisum sativum L. var Alaska) epicotyls through cut bases, supported better growth of apical tissue than supplied glucose and/or fructose. The hexoses were converted mainly to sucrose in basal regions of the epicotyl but some moved as such through the epicotyl and accumulated at the apex (plumule) at a rate faster than sucrose. A greater proportion of the carbon derived from supplied hexoses than from sucrose was used for synthesis of ethanol-insoluble products throughout the epicotyl. By use of asymmetrically labeled sucrose, it was shown that neither hexose moiety was used preferentially for the synthesis of metabolites. Supplied sucrose moved as such only up to the region of cell elongation where it was hydrolyzed and completely equilibrated before moving into more apical regions. The results indicate that better growth with supplied sucrose than hexose could not have resulted from differential effects on cell division, more rapid uptake or transport of sucrose, enhanced wall synthesis, or cleavage by sucrose synthase. It is concluded that transported sucrose versus hexoses must undergo or evoke different reactions which affect growth in the region of cell elongation. 相似文献
235.
236.
Gowrishankar Banumathy Varsha Singh Utpal Tatu 《The Journal of biological chemistry》2002,277(6):3902-3912
The ability of malarial parasite to deploy proteins at the surface of infected erythrocytes is well known. After their synthesis within the parasite, the cargo proteins are exported from the parasite and carried across the erythrocyte cytoplasm to be delivered at the erythrocyte surface. Our knowledge about the mechanisms involved in this complex trafficking path is limited. We have addressed the involvement of chaperones in traffic across erythrocyte cytoplasm. Our analyses of the chaperones available to the parasite indicated that none of the reported chaperones of the parasite origin are present in the erythrocyte cytoplasm. The chaperones of the host (Hsp70, Hsp90, Hop60), on the other hand, were readily detected in the erythrocyte cytosol. Hypotonic lysis and detergent solubilization experiments indicated that unlike their soluble nature in normal erythrocytes, host chaperones are recruited in membrane-bound, detergent-resistant complexes in infected cells. The association of host-Hsp70 with detergent-resistant complexes was ATP-dependent. Importantly, host chaperones could be detected in knob-enriched fractions and could be cross-linked to the knob subunit, PfHRP1, in a large complex at the surface of the infected erythrocytes. Our results implicate host chaperones in the assembly of parasite proteins such as knob subunits at the erythrocyte surface. 相似文献
237.
Neurochemical Research - Asparagus racemosus Willd. (Family Liliaceae), also known as female reproductive tonic, is traditionally used across the Sub-Himalayan region in Uttarakhand, India for... 相似文献
238.
Arvind Kumar Singh Shantanu Prakash RK Garg Parul Jain Rashmi Kumar Amita Jain 《Bioinformation》2021,17(4):506
Host genetic factors are known to determine disease susceptibility in dengue virus infection. Therefore, in this study association of gene polymorphisms of Vitamin D Receptor [rs731236 (Taq) and rs7975232 (Apa1)], Toll-like receptor 2 [rs5743708 (Arg735Gln) and rs5743704 (Pro631His)] and Toll-like receptor 4 [rs4986790A/G(Asp299Gly13843) and rs4986791 C/T(Thr399Ile)] were studied in cases with dengue as compared to controls. Total 98 cases of confirmed dengue virus infection and 98 age, sex and geographically matched healthy controls were enrolled and their genetic polymorphisms for the above mentioned regions were studied by Sanger sequencing. Mutant genotypes CC of VDR rs731236 (Taq1) [(OR 3.808, p value =0.02, CI 1.160-12.498)], GG of VDR rs7975232 (Apa1) [(OR 3.485, p value =0.02, CI 1.162-10.45)] and heterozygous genotypes of TLR4 rs4986790 A/G Asp299Gly [OR 2.40, p value= 0.02, CI 1.12-5.14], TLR4 rs4986791 C/T Thr399Ile [OR 2.09, p value=0.02, CI 1.12-5.14] were found to be significantly more in cases with dengue virus infection as compared to the controls. Also, at these positions mutant alleles were observed in significantly higher number of cases than controls. The values for C allele at VDR rs731236 (Taq1) were OR 1.86, p value 0.009, CI 1.162-3.001; for allele G at rs7975232( Apa1) were OR 2.71, p value 0.006, CI 1.196-2.98 for allele G at TLR4s rs4986790 A/G Asp299Gly were OR 2.35, p value 0.009, CI 1.23-4.50 and for allele T at rs4986791 C/T Thr399Ile were OR 2.36, p value=0.006, CI 1.28-4.38. VDR and TLR4 but not TLR2 gene polymorphisms were found to be associated with dengue susceptibility in Indian population. 相似文献
239.
Saksena Harshita B. Sharma Manvi Singh Dhriti Laxmi Ashverya 《Journal of plant biochemistry and biotechnology.》2020,29(4):687-699
Journal of Plant Biochemistry and Biotechnology - Sugars as an energy source and a signalling molecule are indispensible for growth, development and stress responses in plants. Among sugars,... 相似文献
240.
Bhatnagar Akanksha Singh Shipra Khurana Jitendra P. Burman Naini 《Journal of plant biochemistry and biotechnology.》2020,29(4):590-610
Journal of Plant Biochemistry and Biotechnology - Light acts catalytically to initiate a cascade of events to eventually regulate different aspects of plant development. The cascade of light signal... 相似文献