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71.
Sewa Ram Vinamrata Bhatia Veena Jain B. Mishra 《Journal of plant biochemistry and biotechnology.》2006,15(2):79-83
Low molecular weight (LMW) glutenin subunits represent major part (30%) of storage proteins in wheat endosperm and determine the quality of dough. Despite their importance few LMW glutenin genes have been characterized so far and none from Indian wheat variety. In the present investigation PCR technique was employed to characterize LMW-GS gene representing Glu-B3 locus from Indian bread wheat cultivar NP4. The deduced protein sequence coded by Glu-B3 locus of LMW-GS gene from NP4 showed the presence of regular structure of the repetitive domain with varying numbers of glutamine (Q) residues and the presence of 1st cysteine residue within the repetitive domain at 40th position in mature polypeptide. Such structure might increase and stabilize the gluten polymer through intermolecular interactions of the large numbers of glutamine side chains and cysteine residues for intermolecular disulphide bond formation leading to stronger dough quality of NP4. Moreover, Glu-B3 specific primers could also be used for identifying 1BL/1RS translocation in addition to amplifying LMW glutenin genes. There was no amplification in 1B/1R translocation lines as short arm of wheat was replaced by short arm of rye chromosome in these lines. Such information can be useful in wheat improvement for dough properties for better chapati and bread quality. 相似文献
72.
Mahesh Chandra Alok Kalra Pradeep K. Sharma Rajender S. Sangwan 《Journal of industrial microbiology & biotechnology》2009,36(4):605-609
Capabilities of cellulase production, using delignified bioprocessings of medicinal and aromatic plants, viz. citronella (Cymbopogon winterianus) and Artemisia annua (known as marc of Artemisia) and garden waste (chiefly containing Cynodon dactylon), by the six species of Trichoderma were comparatively evaluated. Among the members of Trichoderma studied, T. citrinoviride was found to be the most efficient producer of cellulases along with a high level of β- glucosidase (produced 102.4 IU g−1 on marc of Artemisia; 101.33 IU g−1 on garden waste; 81.86 IU g−1 on distillation waste of citronella and 94.77 IU g−1 on pure cellulose). Although T. virens was noticed to be the minimal enzyme producer fungus, it interestingly could not produce complete cellulase enzyme complex
on any test waste or pure cellulose, except on marc of Artemisia, where it produced all three enzymes of the complex. Immediate reduction in pH was also noticed during fermentation in the
case of pure polymer (cellulose) by all tested fungi, while it was delayed with delignified agrowastes. The pH profile varied
with the substrate used as well as with individual species of Trichoderma. On the other hand, no alteration in pH with any species of Trichoderma was noticed when grown on marc of A. annua, which might be due to the buffering capacity of this marc. 相似文献
73.
To study the impact of neural activity on cellular physiology, one would like to combine precise control of firing patterns with highly sensitive probes of cellular physiology. Light-gated ion channels, e.g., Channelrhodopsin-2, enable precise control of firing patterns; green fluorescent protein-based reporters, e.g., the GCaMP6f Ca2+ reporter, enable highly sensitive probing of cellular physiology. However, for most actuator-reporter combinations, spectral overlap prevents straightforward combination within a single cell. Here we explore multiwavelength control of channelrhodopsins to circumvent this limitation. The “stoplight” technique described in this article uses channelrhodopsin variants that are opened by blue light and closed by orange light. Cells are illuminated with constant blue light to excite fluorescence of a green fluorescent protein-based reporter. Modulated illumination with orange light negatively regulates activation of the channelrhodopsin. We performed detailed photophysical characterization and kinetic modeling of four candidate stoplight channelrhodopsins. The variant with the highest contrast, sdChR(C138S,E154A), enabled all-optical measurements of activity-induced calcium transients in cultured rat hippocampal neurons, although cell-to-cell variation in expression levels presents a challenge for quantification. 相似文献
74.
Archana Mathur Ajay Kumar Mathur Anita Gangwar Sharawan Yadav Priyanka Verma Rajender Singh Sangwan 《In vitro cellular & developmental biology. Plant》2010,46(1):13-21
A root-derived callus line of Panax sikkimensis that stably accumulates anthocyanins was established by small cell aggregate selection method. The selected line showed a
growth index of 221.36 and an anthocyanin content of 2.76 mg/g fw (7.076% dw) in 50–60 d of growth on a modified MS medium
containing 4.5 μM 2,4-dichlorophenoxy acetic acid and 1.2 μM kinetin under 16-h light and 8-h dark photoperiodic conditions.
Incubation under continuous light increased the growth index to 435.57 but led to a marginal dilution of anthocyanin content
to 2.192 mg/g fw (6.928% dw). The purple-red pigment had absorption maximum at 528 nm. The selected callus line has shown
sustained growth and productivity for more than 6 yr now. Interestingly, pigment accumulation in the selected line did not
hinder the ginsenoside production in the callus tissue (0.9–1.2% fw). 相似文献
75.
A pollen-morphology study of Amaranthus spinosus, A. dubius, and their hybrids has been carried out. Three pollen types have been observed, namely (1) Type A: micrograins; (2) Type B: grains with smaller pores; and (3) Type C: grains with larger pores. Type B is characteristic of A. spinosus, Type C of A. dubius, and the micrograins of the hybrids. Pollen size range, and frequency of the various morphotypes serve to throw light on the biosystematics of the plants studied. 相似文献
76.
77.
Reactive oxygen species play an important role in cancer and metastasis. Kalpaamruthaa is a modified Siddha preparation, which
has been formulated in our laboratory. The preparation is an amalgamation of Semecarpus anacardium (SA), Emblica officinalis (EO) and honey, which gives an extra protectiveness to mammary carcinoma bearing animals (Sprague-Dawley stains were used
for this study). The aim of our research is to determine the therapeutic efficiency of the drug with respect to lipid peroxidation
and antioxidant status. The levels of lipid peroxides and antioxidant levels were measured in blood, and vital organs (liver,
kidney and breast tissue) of control and experimental animals. In cancer condition, the LPO was increased and antioxidant
levels were decreased. On drug (SA and KA) administration, decreased LPO and increased antioxidant levels were seen in control
and experimental animals. This may be due to additive property of the drugs (SA, Emblica and honey), which possesses anticancer effect. The present study shows the good therapeutic efficacy of Kalpaamruthaa against
mammary carcinoma. 相似文献
78.
Cyclic stretch induces PlGF expression in bronchial airway epithelial cells via nitric oxide release
Mohammed KA Nasreen N Tepper RS Antony VB 《American journal of physiology. Lung cellular and molecular physiology》2007,292(2):L559-L566
Mechanical strain of lung tissue is an important stimulus for the production of growth factors that are critical for lung growth and development. However, excessive mechanical strain, as may occur during mechanical ventilation, may produce an increase in growth factors that may contribute to lung injury. We hypothesized that mechanical strain of primary bronchial airway epithelial cells (BAEpCs) induced the production of placental growth factor (PlGF), a member of the VEGF family. BAEpCs were cultured on a deformable silicoelastic membrane and exposed to different magnitudes of stretch. Stretch induced PlGF and nitric oxide (NO) production that increased with increasing magnitude of stretch. Stretch also induced PlGF and inducible NO synthase (iNOS) gene expression. The stretch-induced PlGF production and NO synthesis were attenuated by PD98059, a specific mitogen-activated protein kinase kinase-1 and -2 inhibitor. Inhibition of NO generation by l-NAME or l-NMMA or scavenging NO by carboxy-PTIO prevented stretch-mediated erk1/2 activation. In addition, in unstretched BAEpCs, exogenous NO enhanced erk1/erk2 activation. Our data suggest that mechanical stretch of BAEpCs induces iNOS expression and induces PlGF release in an erk1/2 activation-dependent manner. 相似文献
79.
Sean M. Gibbons Tara Schwartz Jennifer Fouquier Michelle Mitchell Naseer Sangwan Jack A. Gilbert Scott T. Kelley 《Applied and environmental microbiology》2015,81(2):765-773
Human-associated bacteria dominate the built environment (BE). Following decontamination of floors, toilet seats, and soap dispensers in four public restrooms, in situ bacterial communities were characterized hourly, daily, and weekly to determine their successional ecology. The viability of cultivable bacteria, following the removal of dispersal agents (humans), was also assessed hourly. A late-successional community developed within 5 to 8 h on restroom floors and showed remarkable stability over weeks to months. Despite late-successional dominance by skin- and outdoor-associated bacteria, the most ubiquitous organisms were predominantly gut-associated taxa, which persisted following exclusion of humans. Staphylococcus represented the majority of the cultivable community, even after several hours of human exclusion. Methicillin-resistant Staphylococcus aureus (MRSA)-associated virulence genes were found on floors but were not present in assembled Staphylococcus pan-genomes. Viral abundances, which were predominantly enterophages, human papilloma virus, and herpesviruses, were significantly correlated with bacterial abundances and showed an unexpectedly low virus-to-bacterium ratio in surface-associated samples, suggesting that bacterial hosts are mostly dormant on BE surfaces. 相似文献
80.
In Mizoram (Northeast India), rodent outbreaks are known to occur periodically with the onset of bamboo flowering causing a tremendous destruction to food grains and as per the folk belief, often resulting in famine. In an exploratory survey of rodent pests in bamboo growing atreas for their helminth parasite spectrum, metacestodes of tapeworms were frequently encountered infecting the liver lobes and body cavity of the host. The morphological criteria were found to be closely consistent with the metacestode of Taenia species. In molecular characterization of the parasite, the ribosomal DNA (ITS1, ITS2) and mitochondrial COI were amplified and sequenced. Based upon both morphological data and molecular analysis using bioinformatic tools, the metacestode is identified as confirmed to be representing Cysticercus fasciolaris. The adult form of which (Taenia taeniaeformis) commonly occurs in felid and canid mammalian hosts. 相似文献