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991.
992.
B. Devadatha V. V. Sarma Rajesh Jeewon Dhanushka N. Wanasinghe Kevin D. Hyde E. B. Gareth Jones 《Mycological Progress》2018,17(7):791-804
A novel saprobic fungal genus, Thyridariella (Thyridariaceae), is herein described to include Thyridariella mangrovei, the type species and T. mahakoshae spp. nov. Both species were collected as saprobes on decaying wood of Avicennia marina, a common mangrove species found near Kaveri River Delta, Tamil Nadu, on the east coast of India. Thyridariella is diagnosed by having an exclusive combination of characters, such as ascomata with ostiolar necks thickened laterally, hyaline, and centrally constricted muriform ascospores with a single longitudinal septum in each segment and surrounded by a mucilaginous sheath. These characters demarcate these taxa from morphologically similar genera such as Halojulella and Julella. In addition, the new genus also differs from Parathyridaria and Thyridaria in having hyaline, muriform ascospores with distinct mucilaginous sheaths. The monophyly of Thyridariella is well supported in the phylogenetic analysis based on a concatenated dataset from two proteins and three nuclear gene regions. The phylogeny also depicts a sister group relationship of our new genus to Parathyridaria and Thyridaria and hence confirms its position within Thyridariaceae. 相似文献
993.
994.
Efficient and easily scalable protein folding strong anion exchange chromatography for renaturation and simultaneous purification of recombinant human asparaginase from E. coli
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Rajesh Kumar Kante Sandeep Vemula Maheswara Reddy Mallu Srinivasa Reddy Ronda 《Biotechnology progress》2018,34(4):1036-1044
Recombinant proteins are revolutionizing present day therapeutics. They are generally expressed as insoluble inclusion bodies in the E. coli and mis‐folding, loss of protein, and high cost of down streaming are the hurdles in their recovery. For the first time, we are reporting the refolding with simultaneous purification of rhASP in E. coli using a single step utilizing protein folding‐strong anion exchange chromatography (PF‐SAX). The purification method is also standardized for optimal concentration of solution additives, pH, and mobile phase composition. The results showed purification of rhASP with anion exchange chromatography was effective. Phosphate buffer and slightly alkaline pH produced significant recovery yields and purity profiles. The effect of solution additives such as arginine, glycerol, TMAO, sorbitol, dextran, glutamate, and fructose on rhASP renaturation is also investigated. Significant results were achieved using arginine‐TMAO combination in terms of purity, recovery yield and specific activity of 99%, 78%, and 210 IU/mg, respectively. The work concludes that PF‐SAX refolding method is superior to other conventional methods and it can be applied to large scale purification of rhASP produced in E. coli. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1036–1044, 2018 相似文献
995.
Nitric oxide (NO) acts as a modulator of neuronal transmission in mature neuronal systems, including the retina. Recently,
NO has also been suggested to have a trophic function during development. We examined immunocytochemically the distribution
of NO-producing cells in developing and transplanted rabbit retinas. An antibody detecting the neuronal isoform of its biosynthetic
enzyme, nitric oxide synthase (NOS), was used on normal developing retinas [starting at embryonic day (E) 15] and on rabbit
retinal transplants after various survival times (1–139 days after surgery). Weakly stained cell bodies were first observed
in the proximal margin of the neuroblastic layer at E 29. Stained processes projecting towards a developing inner plexiform
layer were also visible at this time point. Immunoreactive cells were located at later stages in the innermost part of the
inner nuclear layer and in the ganglion cell layer, and are likely to correspond mainly to amacrine cells. NOS-labelled cells
were also found in retinal transplants. The first NOS-labelled cells appeared, as in normal developing retinas, in ages corresponding
to E 29 and were still detected in transplants corresponding to postnatal day 123. NOS-labelled cells were seen in areas between
rosettes, where amacrine cells are located. NOS-labelled processes were at times seen to project for long distances, forming
very distinct plexuses. NOS-containing amacrine cells thus appear both in the transplants and in developing retinas in the
embryonic stages, long before synaptic function involving these cells can be expected, suggesting a role for NO not only in
neuromodulation but also in retinal development.
Accepted: 22 January 1997 相似文献
996.
997.
The plant growth, net photosynthetic rate (PN), intercellular CO2 concentration (ci), and dry matter production of Ceriops roxburghiana Arn. were significantly increased with increasing salinity from 0 to 400 mM NaCl. At 600 mM NaCl, shoot and root lengths, and dry mass were significantly depressed with respect to control. Absence of diurnal fluctuation of concentrations of organic acids, and the low activity of phosphoenolpyruvate carboxylase and high activity of ribulose-1,5-bisphosphate carboxylase confirmed the operation of C3 pathway in Ceriops even at increasing salinity. 相似文献
998.
Vikas Misra Hannah Lee Anju Singh Kewu Huang Rajesh K Thimmulappa Wayne Mitzner Shyam Biswal Clarke G Tankersley 《Physiological genomics》2007,31(3):429-440
This study identified gene expression profiles that provided evidence for genomic mechanisms underlying the pathophysiology of aging lung. Aging lungs from C57BL/6 (B6) and DBA/2 (D2) mouse strains differ in physiology and morphometry. Lungs were harvested from B6 mice at 2, 18, and 26 mo and from D2 mice at 2 and 18 mo of age. Purified RNA was subjected to oligonucleotide microarray analyses, and differential expression analyses were performed for comparison of various data sets. A significant majority of differentially expressed genes were upregulated with aging in both strains. Aging D2 lungs uniquely exhibited upregulation in stress-response genes including xenobiotic detoxification cascades. In contrast, aging B6 lungs showed downregulation of heat shock-response genes. Age-dependent downregulation of genes common to both B6 and D2 strains included several collagen genes (e.g., Col1a1 and Col3a1). There was a greater elastin gene (Eln) expression in D2 mice at 2 mo, and Eln was uniquely downregulated with age in this strain. The matrix metalloproteinase 14 gene (Mmp14), critical to alveolar structural integrity, was also downregulated with aging in D2 mice only. Several polymorphisms in the regulatory and untranslated regions of Mmp14 were identified between strains, suggesting that variation in Mmp14 gene regulation contributes to accelerated aging of lungs in D2 mice. In summary, lungs of B6 and D2 mice age with variable rates at the gene expression level, and these quantifiable genomic differences provide a template for understanding the variability in age-dependent changes in lung structure and function. 相似文献
999.
Steve Hamner Susan C. Broadaway Veer Bhadra Mishra Anshuman Tripathi Rajesh Kumar Mishra Elinor Pulcini Barry H. Pyle Timothy E. Ford 《Applied microbiology》2007,73(7):2369-2372
Escherichia coli serotype O157:H7 was detected among bacteria collected from the Ganges River. O157:H7 isolates tested positive for stx1, stx2, and eae gene sequences. Identification of potentially pathogenic isolates from extensively used source water indicates that O157:H7 may be a significant but as yet underacknowledged public health concern in India. 相似文献
1000.
Vinnakota Rajesh Ramakrishnan Anantha Maharasi Samdani A. Venugopal M. Anjali Ram B. Sri Krishnan S. Navaneetha Murugesan Dhandapani Sankaranarayanan Kavitha 《Protoplasma》2016,253(6):1593-1597
Protoplasma - Climate change drastically affects the cultivation of rice, and its production is affected significantly by water stress. Adaptation of a plant to water deficit conditions is... 相似文献