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191.
192.
A Sadeghi E Karimi PA Dahaji MG Javid Y Dalvand H Askari 《World journal of microbiology & biotechnology》2012,28(4):1503-1509
A biocontrol Streptomyces isolate (C) was tested for its plant growth promoting qualities under saline conditions. Exposure to elevated osmotic strengths up to 300 mM NaCl increased dry weight and cfu/ml significantly. The isolate C produced indolyl-3-acetic acid (IAA) into the medium in the amount of 2.4 μg/ml. The amount of auxin increased after adding salt and reached to 4.7 μg/ml in 300 mM NaCl. Biosynthesis of siderophore was detectable and increased in presence of NaCl. Streptomyces isolate C showed good solubilization of tricalcium phosphate in culture medium with 92 mg/l. Solubilization decreased in presence of NaCl. Soil treatment with isolate C increased the growth and development of wheat plant in normal and saline conditions. In this treatment there were significant increases in germination rate, percentage and uniformity, shoot length and dry weight compared to the control. Applying the bacterial inocula increased the concentration of N, P, Fe and Mn in wheat shoots grown in normal and saline soil, but had non-significant effect on other micro and macronutrients concentrations. Results of this study show that Streptomyces isolate C has potential to be utilized as biofertilizer in saline soils. 相似文献
193.
Molecular basis of the structural stability of hemochromatosis factor E: A combined molecular dynamic simulation and GdmCl‐induced denaturation study
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Parvez Khan Amresh Parkash Asimul Islam Faizan Ahmad Md. Imtaiyaz Hassan 《Biopolymers》2016,105(3):133-142
Hemochromatosis factor E (HFE) is a member of class I MHC family and plays a significant role in the iron homeostasis. Denaturation of HFE induced by guanidinium chloride (GdmCl) was measured by monitoring changes in [θ]222 (mean residue ellipticity at 222 nm), intrinsic fluorescence emission intensity at 346 nm (F346) and the difference absorption coefficient at 287 nm (Δε287) at pH 8.0 and 25°C. Coincidence of denaturation curves of these optical properties suggests that GdmCl‐induced denaturation (native (N) state ? denatured (D) state) is a two‐state process. The GdmCl‐induced denaturation was found reversible in the entire concentration range of the denaturant. All denaturation curves were analyzed for , Gibbs free energy change associated with the denaturation equilibrium (N state ? D state) in the absence of GdmCl, which is a measure of HFE stability. We further performed molecular dynamics simulation for 40 ns to see the effect of GdmCl on the structural stability of HFE. A well defined correlation was established between in vitro and in silico studies. © 2015 Wiley Periodicals, Inc. Biopolymers 105: 133–142, 2016. 相似文献
194.
Kaveh Javanshir Javid Hamidreza Alizadeh 《Archives Of Phytopathology And Plant Protection》2016,49(17-18):471-484
The purpose of this study was to investigate the effects of isolates T22, T9 and T6 of Trichoderma harzianum on isolate F42 of Fusarium oxysporum f. sp. radicis-cucumerinum. The effect of T. harzianum isolates on controlling disease was examined under greenhouse conditions. Results showed that these three isolates, respectively, had the high effect on inhibition of pathogen growth. In examining the severity of disease in the greenhouse, it was found that isolate T22 had the greatest effect on controlling the pathogen. The results of volatile compounds showed that these isolates, respectively, were effective in reducing mycelial growth of isolate F42. The highest peroxidase activity was observed on the fourth day in isolate T6 and the highest phenylalanine ammonia lyase enzyme activity was observed on the fifth day in isolate T22. Based on the results, isolate of T22 showed the greatest effect on the induction of resistance against F42 and may be a successful agent for biological control of root and stem rot of cucumber. 相似文献
195.
Wajihul Hasan Khan V. L. N. Raghuram Srungaram Asimul Islam Ilyas Beg Md. Shakir H. Haider Faizan Ahmad 《Preparative biochemistry & biotechnology》2016,46(5):483-488
Human respiratory syncytial virus (hRSV) is an important pathogen of acute respiratory tract infection. The G protein of hRSV is a transmembrane glycoprotein that is a neutralizing antigen and is thus a vaccine candidate. In this study, synthetic codon optimized ectodomain G protein [G(ΔTM)] of BA genotype of group B hRSV was cloned, expressed, and characterized using biophysical techniques. The molar absorption coefficient and mean residue ellipticity at 222 nm ([θ]222) of G (ΔTM) was found to be 7950 M?1 cm?1 and ?19701.7 deg cm2 dmol-1 respectively. It was concluded that G(ΔTM) mainly consist of α-helix (74.9%) with some amount of β-sheet (4%). The protein was stable up to 85°C without any transition curve. However, heat-induced denaturation of G(ΔTM) resulted in total loss of β-sheet whereas not much change was observed in the α-helix part of the secondary structure. It was concluded that G(ΔTM) is an α-helical protein and it is highly stable at high temperature, but could be easily denatured using high concentrations of GdmCl/urea or acidic condition. This is the first investigation of cloning, expression, and characterization of G(ΔTM) of BA viruses from India. Structural characterization of G protein will assist in drug designing and vaccine development for hRSV. 相似文献
196.
Farha Naz Parvesh Singh Asimul Islam Faizan Ahmad 《Journal of biomolecular structure & dynamics》2016,34(6):1241-1251
MAP/microtubule affinity-regulating kinase 4 (MARK4) is a member of adenosine monophosphate-activated protein kinases, directly associated with cancer and neurodegenerative diseases. Here, we have cloned, expressed, and purified two variants of MARK4 [the kinase domain (MARK4-F2), and kinase domain along with 59 N-terminal residues (MARK4-F1)] and compared their stability at varying pH range. Structural and functional changes were observed by incubating both forms of MARK4 in buffers of different pH. We measured the secondary structure of MARK4 using circular dichroism and tertiary structure by measuring intrinsic fluorescence and absorbance properties along with the size of proteins by dynamic light scattering. We observed that at extremes of pH (below pH 3.5 and above pH 9.0), MARK4 is quite stable. However, a remarkable aggregate formation was observed at intermediate pH (between pH 3.5 and 9.0). To further validate this result, we have modeled both forms of MARK4 and performed molecular dynamics simulation for 15 ns. The spectroscopic observations are in excellent agreement with the findings of molecular dynamics simulation. We also performed ATPase activity at varying pH and found a significant correlation of structure of MARK4 with its enzyme activity. It is interesting to note that both forms of MARK4 are showing a similar pattern of structure changes with reference to pH. 相似文献
197.
Zareef M Iqbal R De Dominguez NG Rodrigues J Zaidi JH Arfan M Supuran CT 《Journal of enzyme inhibition and medicinal chemistry》2007,22(3):301-308
A series of new benzenesulfonamides, most of which are chiral, incorporating 1, 3, 4-oxadiazole and amino acid moieties have been synthesized. Some of these compounds were screened for antimalarial activity and also evaluated for their ability to inhibit hem polymerization. The electrophoretic analysis indicated that one compound was effective in inhibiting the degradation of hemoglobin. The synthesized compounds were tested in mice infected with Plasmodium berghei. These derivatives have the potential for the development of novel antimalarial lead compounds. 相似文献
198.
Meenu Maheshwari Abdullah Safar Althubiani Hussein Hasan Abulreesh Faizan Abul Qais Mohd Shavez Khan Iqbal Ahmad 《Saudi Journal of Biological Sciences》2019,26(7):1848-1855
The widespread occurrence of extended spectrum β-lactamases (ESβLs) producing enteric bacteria and their co-resistance with flouroquinolones has impaired the current antimicrobial therapy. This has prompted the search for new alternatives through synergistic approaches with herbal extracts. In this study Carum copticum (seeds) was extracted first in methanol and then subsequently extracted in different organic solvents. MIC of plant extracts, ciprofloxacin and thymol was determined by broth micro-dilution method using TTC. Synergism between plant extracts and ciprofloxacin was assayed by the checkerboard method. Chemical constituents of active extracts were analyzed by GC-MS. Methanolic, hexane and ether extract of Carum copticum exhibited significant antibacterial activity with MIC values ranged from 0.25 mg/ml to 2.0 mg/ml. Synergy analysis between Carum copticum extracts and ciprofloxacin combinations revealed FIC index in the range of 0.093–0.25. About 81% ciprofloxacin resistant ESβL producing enteric bacteria were re-sensitized in the presence of 15.6–250 μg/ml of methanolic extract of Carum copticum. Moreover, ciprofloxacin showed 8 to 64 folds reduction in MIC in presence of 250 and 500 μg/ml of hexane extract. Whereas, 4–32 folds reduction in MIC of ciprofloxacin was achieved in the presence of 31.25 and 62.5 μg/ml of ether extract, indicating synergistic enhancement of drug activity. The chemical analysis of hexane and ether extracts by GC-MS revealed the common occurrence of one or more phenolic hydroxyl at different locations on benzene ring. This study demonstrated the potential use of herbal extract of Carum copticum in combination therapy against ESβL producing bacteria. 相似文献
199.
Md. Khurshid Alam Khan Md. Hamidur Rahaman Md. Imtaiyaz Hassan Tej P. Singh Ali A. Moosavi-Movahedi Faizan Ahmad 《Journal of biological inorganic chemistry》2010,15(8):1319-1329
It has already been shown that the mutant Leu94Gly of horse cytochrome c exists in a molten globule (MG) state. We have carried out studies of reversible folding and unfolding induced by LiCl of
this mutant at pH 6.0 and 25 °C by observing changes in the difference molar absorption coefficient at 402 nm, the mean residue
ellipticity at 222 nm, and the difference mean residue ellipticity at 409 nm. This process is a three-state process when measured
by these probes. The stable folding intermediate state has been characterized by far- and near-UV circular dichroism, tryptophan
fluorescence, 8-anilino-1-naphthalenesulfonic acid binding, and dynamic light scattering measurements, which led us to conclude
that the intermediate is a premolten globule (PMG). Analysis of the reversible unfolding transition curves for the stability
of different states in terms of the Gibbs free energy change at pH 6.0 and 25 °C led us to conclude that the MG state is more
stable than the PMG state by 5.4 ± 0.1 kcal mol−1, whereas the PMG state is more stable than the denatured (D) state by only 1.1 ± 0.1 kcal mol−1. A comparison of the conformational and thermodynamic properties of the LiCl-induced PMG state at pH 6.0 with those of the
PMG state induced by NaCl at pH 2.0 suggests that a similar PMG state is obtained under both denaturing conditions. Differential
scanning calorimetry measurements suggest that heat induces a reversible two-state transition between MG and D states. 相似文献
200.
Kyle R. Grant T. Jonathan Davies Sachin Medigeshi Harish Javid Ahmad Dar Subashree Kothandaraman Tapas Ray Dinesh Malasiya Selvadurai Dayanandan Mohammed Latif Khan 《Diversity & distributions》2023,29(7):946-958