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Qazi Mohd Sajid Jamal Mohtashim Lohani Mohd Haris Siddiqui Mohd Haneef Shailendra Kumar Gupta Gulshan Wadhwa 《Bioinformation》2012,8(17):795-800
DNA damage occurs almost all the times in cells, but is repaired also continuously. Occurrence of all these mutations and their
accumulation in one cell which finally becomes tumorigenic/carcinogenic appears possible if the DNA repair mechanism is
hampered. We hypothesize that alterations in DNA repair pathways, either all or at least at one i.e. genetic, translational or posttranslational
level, becomes quite imperative for the initiation and progression of Cancer. Therefore, we investigated the interaction
capability of some carcinogens with the enzymes involved in the DNA repair mechanisms. Cigarette smoke''s derivatives like
NNK and NNAL are well established carcinogens. Hence, we analyzed 72 enzymes involved in the DNA repair Mechanisms for
their interactions with ligands (NNK and NNAL). The binding efficiencies with enzymes ranging from +36.96 to -7.47 Kcal/Mol.
Crystal Structure of Human Carbonmonoxy-Haemoglobin at 1.25 Å Resolution, PDB ID-1IRD as a +Ve control, showed
binding energy -6.31 to -6.68 Kcal/Mol. and Human heat shock factor-binding protein 1, PDB ID- 3CI9 as a -Ve control, showed -
3.91 to +2.09 Kcal/Mol. Binding was characterized for the enzymes sharing equivalent or better interaction as compared to +Ve
control. Study indicated the loss of functions of these enzymes, which probably could be a reason for fettering of DNA repair
pathways resulting in damage accumulation and finally cancer formation. 相似文献
55.
Salinity is one of the most important stresses that hamper agricultural productivity in nearly every part of the world. Enhanced biosynthesis of ethylene in plants under salinity stress is well established. Higher ethylene concentration inhibits root growth and ultimately affects the overall plant growth. Overcoming this ethylene-induced root inhibition is a prerequisite for successful crop production. Recent studies have shown that ethylene level in plants is regulated by a key enzyme 1-aminocyclopropane-1-carboxylicacid (ACC)-deaminase. This enzyme is present in plant growth-promoting bacteria (PGPR) and lowers the ethylene level by metabolizing its precursor ACC into α-ketobutyrate and ammonia (NH3). Inoculation of plants under salinity stress with PGPR having ACC-deaminase activity mitigates the inhibitory effects of salinity on root growth by lowering the ethylene concentration in the plant. This in turn results in prolific root growth, which is beneficial for the uptake of nutrients and maintenance of growth under stressful environment. The present review critically discusses the effects of salinity stress on plant growth with special reference to ethylene production and the effects of rhizobacteria containing ACC-deaminase on crop improvement under salinity stress. It also discusses how much progress has been made in producing transgenic lines of different crops over-expressing the gene encoding ACC-deaminase and how far such transformed lines can tolerate salinity stress. 相似文献
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Antje Bodensieck Walter M.F. Fabian Olaf Kunert Ferdinand Belaj Sajid Jahangir Wolfgang Schühly Rudolf Bauer 《Chirality》2010,22(3):308-319
In‐depth conformational analyses of 10 known eremophilane (= (1S,4aR,7R,8aR)‐decahydro‐1,8a‐dimethyl‐7‐(1‐methylethyl)napththalene) sesquiterpenes, 1 – 10 , from Petasites hybridus were performed with molecular mechanics as well as density functional theory methods. Electronic transition energies and rotational strengths of these eight eremophilane lactones and two petasins were calculated by time‐dependent density functional theory (B3PW91/TZVP). The absolute configurations of the constituents could be assigned by comparison of their simulated and experimental circular dichroism (CD) spectra in methanol as (4S,5R,8S,10R) ( 1 , 2 ), (2R,4S,5R,8S,10R) ( 3 , 4 , 5 ), (2R,4S,5R,8R,9R,10R) ( 6 ), (2R,4S,5R,8R,10R) ( 7 , 8 ), and (3R,4R,5R) ( 9 , 10 ). Single‐crystal X‐ray diffraction data of 8β‐hydroxyeremophilanolide ((8S)‐8‐hydroxyeremophil‐7(11)‐en‐12,8‐olide) ( 1 ) served as starting point for the theoretical conformational calculations of the 8β‐epimers of the eremophilane lactones. Experimental CD spectra as well as 1H NMR spectra of compound 1 in methanol were considerably dependent on sample concentration. Chirality, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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Waheed Ullah Khan Sajid Rashid Ahmad Aamir Ali Aqeel Ahmad Waheed Akram 《International journal of phytoremediation》2018,20(6):581-592
The current study was performed to assess the effect of Burkholderia cepacia CS8 on the phytoremediation of cadmium (Cd) by Catharanthus roseus grown in Cd-contaminated soil. The plants cultivated in Cd amended soil showed reduced growth, dry mass, gas-exchange capacity, and chlorophyll contents. Furthermore, the plants exhibited elevated levels of malondialdehyde (MDA) and hydrogen peroxide (H2O2) under Cd stress. The bacterized plants showed higher shoot length, root length; fresh and dry weight. The improved stress tolerance in inoculated plants was attributed to the reduced quantity of MDA and H2O2, enhanced synthesis of protein, proline, phenols, flavonoids, and improved activity of antioxidant enzymes including peroxidase, superoxide dismutase, ascorbate peroxidase, and catalase. Similarly, the 1-aminocyclopropane-1-carboxylate deaminase activity, phosphate solubilization, auxin, and siderophore production capability of B. cepacia CS8 improved growth and stress alleviation in treated plants. The bacterial inoculation enhanced the amount of water extractable Cd from soil. Furthermore, the inoculated plants showed higher bioconcentration factor and translocation factor. The current study exhibits that B. cepacia CS8 improves stress alleviation and phytoextraction potential of C. roseus plants growing under Cd stress. 相似文献
59.
Williamson AL Lecchi P Turk BE Choe Y Hotez PJ McKerrow JH Cantley LC Sajid M Craik CS Loukas A 《The Journal of biological chemistry》2004,279(34):35950-35957
Blood-feeding pathogens digest hemoglobin (Hb) as a source of nutrition, but little is known about this process in multicellular parasites. The intestinal brush border membrane of the canine hookworm, Ancylostoma caninum, contains aspartic proteases (APR-1), cysteine proteases (CP-2), and metalloproteases (MEP-1), the first of which is known to digest Hb. We now show that Hb is degraded by a multi-enzyme, synergistic cascade of proteolysis. Recombinant APR-1 and CP-2, but not MEP-1, digested native Hb and denatured globin. MEP-1, however, did cleave globin fragments that had undergone prior digestion by APR-1 and CP-2. Proteolytic cleavage sites within the Hb alpha and beta chains were determined for the three enzymes, identifying a total of 131 cleavage sites. By scanning synthetic combinatorial peptide libraries with each enzyme, we compared the preferred residues cleaved in the libraries with the known cleavage sites within Hb. The semi-ordered pathway of Hb digestion described here is surprisingly similar to that used by Plasmodium to digest Hb and provides a potential mechanism by which these hemoglobinases are efficacious vaccines in animal models of hookworm infection. 相似文献
60.
Clan CD cysteine peptidases of parasitic protozoa 总被引:4,自引:0,他引:4
Parasitic protozoa contain an abundance of cysteine peptidases that are crucial for a range of important biological processes. The most studied cysteine peptidases of parasitic protozoa belong to the group of papain-like enzymes known as clan CA. However, several more recently identified cysteine peptidases differ fundamentally from the clan CA enzymes and have been included together in clan CD. Enzymes of this clan have now been identified in parasitic protozoa. Many have important roles and also differ significantly from known mammalian counterparts. The main characteristics of clan CD enzymes are outlined here, in particular glycosylphosphatidylinositol (GPI):protein transamidase, metacaspase and separase, and their differences from the clan CA enzymes are described. 相似文献