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61.
Mishra Aradhana Singh Satyendra Pratap Mahfooz Sahil Shukla Richa Mishra Nishtha Pandey Shipra Dwivedi Sanjay Pandey Vivek Shirke Pramod Arvind Nautiyal Chandra Shekhar 《Plant Molecular Biology Reporter》2019,37(5-6):499-499
Plant Molecular Biology Reporter - The original version of this article unfortunately contained missing information at author’s affiliations. The affiliation address of the author’s... 相似文献
62.
63.
AbstractDesert plant species commonly use seed dormancy to prevent germination during unfavorable environmental conditions and thus increase the probability of seedling survival. Seed dormancy presents a challenge for restoration ecology, particularly in desert species for which our knowledge of dormancy regulation is limited. In the present study the effect of gibberellic acid (GA3) and potassium nitrate (KNO3) on seed dormancy release was investigated on eight Arabian desert species. Both treatments significantly enhanced the germination of most species tested. GA3 was more effective than KNO3 in enhancing germination percentage, reducing mean germination time and synchronizing the germination in most of the studied species. Light requirement during germination was species-specific, but in general the presence of light promoted germination more effectively when combined with KNO3 and GA3. The wide variation in dormancy and germination requirements among the tested species is indicative of distinct germination niches, which might assist their co-existence in similar habitat/environmental conditions. Seed pre-treatments that optimize germination in this habitat must therefore be assessed for individual species to improve the outcomes of ecological restoration. 相似文献
64.
The success of P. juliflora, an evergreen woody species has been largely attributed to temperature acclimation and stomatal control of photosynthesis
under wide range of environmental conditions prevalent in India. We studied the contribution of the enzyme ribulose-1,5 bisphosphate
carboxylase/oxygenase (Rubisco) in diurnal and seasonal photosynthesis changes in P. juliflora. The changes observed in photosynthesis under natural conditions could be effected by the growth temperatures, which ranged
from 10–30 °C in winter to 30–47 °C in summer. However, the Total Rubisco activity displayed a constant diurnal pattern and
showed a maximum at 1200 in all seasons namely spring, summer, monsoon and winter irrespective of the changes in temperature.
The Total Rubisco activity from two cohorts of leaves produced in spring and monsoon appeared to be down-regulated differentially
at low PPFD during the evening. The in vivo and in vitro measurements of carboxylation efficiency of Rubisco showed wide variation during the day and were correlated with the photosynthesis
rate. The light activation of Rubisco showed the acclimation to moderately high temperatures in different seasons except in
summer. The exceptionally high temperatures (>45 °C) in summer, though not affecting Total activity, severely inhibited the
light activation of Rubisco and also modulated the recovery process for the activation of Rubisco. Our studies suggest that
the modulation of Rubisco driven by Rubisco activase and not Rubisco per se was crucial for the diurnal regulation of photosynthesis.
NBRI Publication No.: 528 相似文献
65.
Sutton JC Bolton SA Davis ME Hartl KS Jacobson B Mathur A Ogletree ML Slusarchyk WA Zahler R Seiler SM Bisacchi GS 《Bioorganic & medicinal chemistry letters》2004,14(9):2233-2239
A series of nonguanidine N1-activated C4-carboxy azetidinone tryptase inhibitors was prepared by solid-phase methodology to quickly assess the SAR associated with distal functionality on the N1-activating group. From these studies, potent inhibitors with improved specificity were discovered. 相似文献
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Bhat BA Ponnala S Sahu DP Tiwari P Tripathi BK Srivastava AK 《Bioorganic & medicinal chemistry》2004,12(22):5857-5864
A number of thiazolidine-2,4-diones derivatives having carboxylic ester appendage at N-3 were synthesized and their antihyperglycemic activity was evaluated. Many of these derivatives as well as their corresponding carboxylic acid showed significant improvement on post-prandial hyperglycemia in normal rats, in contrast to their poor agonist activity at PPARgamma. 相似文献
68.
Biaryls, 7-naphthyl-5-s-amino-2,3-dihydrobenzo[b]thiophene-4-carbonitriles (3a-e), 8-(1-naphthyl)-6-s-amino-isothiochroman-5-carbonitriles (6a-d), 4-(1-naphthyl)-2-s-aminobezocycloalkene-1-carbonitriles (6e-j), 8-naphthyl-6-s-amino-2-ethyl-1,2,3,4-tetrahydro-isoquinoline-5-carbonitrle (6k-n), 1-naphthyl-3-s-amino-10H-9-thia-phenantherene-4-carbonitriles (8a-e) and 1-(1-naphthyl)-3-s-amino-9,10-dihydrophenantherene-4-carbonitriles (8f-i) have been prepared through carbanion induced ring transformation reactions of 6-naphthyl-3-cyano-4-s-amino-2H-pyran-2-ones (1) from respective ketones (2, 5, and 7). These compounds have been evaluated for their glucose-6-phosphatase inhibitory activity and only 6a, c, j, m, c, d, h displayed significant inhibition of the glucose-6-phosphatase. 相似文献
69.
The effect of NaCl on two vital processes of cyanobacterial metabolism, viz. N(2) fixation and oxygenic photosynthesis, was studied in the cyanobacterium Nostoc muscorum grown diazotrophically. An increase in NaCl concentration suppressed the formation of heterocyst and adversely affected the nitrogenase activity in the parent, whereas in Li(+)-R and Na(+)-R mutants NaCl stress did not cause any adverse effect. The rate of photosynthetic O(2)-evolution was also adversely affected by the NaCl stress, but the magnitude was less than that of nitrogenase activity. L-Proline, the well-known osmoprotectant, provided protection to the cyanobacterium against NaCl stress. The parent strain utilized L-proline as a nitrogen source and suppressed heterocyst formation and nitrogenase activity, while mutants showed normal heterocyst frequency and nitrogenase activity. Therefore, it may be that the proline metabolism is altered as a result of mutation. The intracellular levels of proline in the parent were enhanced about threefold in the medium containing 1 mol x m(-3) proline, while in mutants there was no significant increase in the intracellular level of proline. In the medium containing both NaCl and proline, the intracellular level of proline was enhanced in the parent as well as in both mutant strains. This suggests that the parent strain possessed both normal proline uptake and salt-induced proline uptake systems, whereas the mutant strains were defective in normal proline uptake and had only salt-induced proline uptake. The over-accumulation of proline in the presence of NaCl stress is due either to the loss of proline oxidase activity or to the accumulation of exogenous proline. 相似文献
70.
Tendulkar AV Wangikar PP Sohoni MA Samant VV Mone CY 《Journal of molecular biology》2003,334(1):157-172
We present a scheme for the classification of 3487 non-redundant protein structures into 1207 non-hierarchical clusters by using recurring structural patterns of three to six amino acids as keys of classification. This results in several signature patterns, which seem to decide membership of a protein in a functional category. The patterns provide clues to the key residues involved in functional sites as well as in protein-protein interaction. The discovered patterns include a "glutamate double bridge" of superoxide dismutase, the functional interface of the serine protease and inhibitor, interface of homo/hetero dimers, and functional sites of several enzyme families. We use geometric invariants to decide superimposability of structural patterns. This allows the parameterization of patterns and discovery of recurring patterns via clustering. The geometric invariant-based approach eliminates the computationally explosive step of pair-wise comparison of structures. The results provide a vast resource for the biologists for experimental validation of the proposed functional sites, and for the design of synthetic enzymes, inhibitors and drugs. 相似文献