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1.
New antineoplastic series of substituted benzothiazolo-β-aminobisphosphonic acids have been developed on the basis of the prospecting potency of the benzothiazole motifs and the aminomethylenebisphosphonate moiety as well as on the prediction of the biological activity utilizing computer program PASS, version 2014-1. Target compounds were obtained in excellent yields (70–90%) via Phospha–Michael-type addition reaction of tetraethyl methylene-1,1-bisphosphonate reagent to a group of Schiff bases incorporating benzothiazole moiety. The reactions proceeded under microwave irradiation, utilizing the advantages of the environment, friendly protocol such as high efficiency, short reaction time, and excellent yields. In consistency with the prospected results, the new NBP acids revealed positive properties against human breast and colon tumor cell lines. Remarkable potency for six lead compounds (out of 12) was observed against breast (MCF7, MDAMB/435, MDAMB/231/ATCC, HS-578T with GI50: 2.05–6.47 μM) and colon (COLO-205, HCT-116, HCC-2998, and SW-620 with GI50: 3.03–7.92 μM) carcinoma cell lines when compared with the positive control Adriamycin (breast, GI50: 3.27–6.64 μM; colon, GI50: 4.09–8.75 μM). Notably, there is a consistency between the prediction and the determined biological results.  相似文献   

2.
Numerous desulfurizing bacteria from the Rhodococcus genus harbor conserved dsz genes responsible for the degradation of sulfur compounds through 4S pathway. This study describes a newly identified desulfurizing bacterium, Rhodococcus sp. FUM94, which unlike previously identified strains encodes a truncated dsz operon. DNA sequencing revealed a frameshift mutation in the dszA gene, which led to an alteration of 66 amino acids and deletion of other C-terminal 66 amino acids. The resulting DszA polypeptide was shorter than DszA in Rhodococcus sp. IGTS8 reference strain. Despite the truncation, desulfurizing activity of the operon was observed and attributed to the removal of an overlap of dszA and dszB genes, and lack of active site in the altered region. Desulfurization experiments resulted in specific production rate of 6.3 mmol 2-hydroxy biphenyl (kgDCW)?1 h?1 at 2 g l?1 biocatalyst concentration and 68.8% biodesulfurization yield at 20 g l?1 biocatalyst concentration, both at 271 μM dibenzothiophene concentration which is comparable to similar wild-type biocatalysts.  相似文献   

3.
Laser electrospray mass spectrometry (LEMS) measurement of the dissociation constant (Kd) for hen egg white lysozyme (HEWL) and N,N′,N″-triacetylchitotriose (NAG3) revealed an apparent Kd value of 313.2?±?25.9 μM for the ligand titration method. Similar measurements for N,N′,N″,N″’-tetraacetylchitotetraose (NAG4) revealed an apparent Kd of 249.3?±?13.6 μM. An electrospray ionization mass spectrometry (ESI-MS) experiment determined a Kd value of 9.8?±?0.6 μM. In a second LEMS approach, a calibrated measurement was used to determine a Kd value of 6.8?±?1.5 μM for NAG3. The capture efficiency of LEMS was measured to be 3.6?±?1.8% and is defined as the fraction of LEMS sample detected after merging with the ESI plume. When the dilution is factored into the ligand titration measurement, the adjusted Kd value was 11.3 μM for NAG3 and 9.0 μM for NAG4. The calibration method for measuring Kd developed in this study can be applied to solutions containing unknown analyte concentrations.
Graphical Abstract
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4.
A series of [1,2,4]triazolo[4,3-a]pyridine derivatives bearing a sulfide substructure was designed, synthesized and characterized via 1H·NMR, 13C·NMR, IR and elemental analyses. Bioassay Results indicated some of the derivatives displayed good fungicidal activity on Rhizoctonia cerealis, moderated insecticidal activity against Plutella xylostella and good insecticidal activity on Helicoverpa armigera. The inhibitory effects of compounds 4g and 4u against Rhizotonia cerealis were 70.9% at 50 μg mL?1; the IC50 values of compounds 4d and 4s against Plutella xylostella were 43.87 and 50.75 μg mL?1, respectively. And the IC50 values of compounds 4d, 4q, and 4s on Helicoverpa armigera were 58.3, 77.14 and 65.31 μg mL?1, respectively, which were better than that of commercial chlorpyrifos (103.77 μg mL?1).  相似文献   

5.
This paper is focused on a characterization of bacterial contamination in pool water of the interim spent fuel storage (JAVYS Inc.) in Slovak Republic and on bioaccumulation of 137Cs and 60Co by isolated bacteria. Bacterial community in pool water is kept on very low level by extremely low concentration of solutes in deionized water and by the efficient water filtration system. Based on standard methods and sequencing of 16S rDNA four pure bacterial cultures were identified as Kocuria palustris, Micrococcus luteus, Ochrobactrum spp. and Pseudomonas aeruginosa. Isolated aerobic bacteria were able to bioaccumulate 137Cs and 60Co in laboratory experiments. The mechanism of Co and Cs binding involve rapid interactions with anionic groups of the components of cell surface and in the case of Cs+ ions is followed by transport processes across cytoplasm membranes and by intracellular distribution. The maximum specific uptake of Cs+ after 48 h cultivation in mineral medium (MM) reached 7.54 ± 0.48 μmol g?1 dw (Ochrobactrum spp.), 19.6 ± 0.1 μmol g?1 dw (M. luteus) and 20.1 ± 2.2 μmol g?1 dw (K. palustris). The maximum specific uptake of Co2+ after 24 h cultivation in MM reached 31.1 ± 3.5 μmol g?1 dw (Ochrobactrum spp.), 86.6 ± 12.2 μmol g?1 dw (M. luteus) and 16.9 ± 1.2 μmol g?1 dw (K. palustris). These results suggest that due to the long lasting uptake of 137Cs, 60Co and other radionuclides by biofilm in pool water high specific radioactivities (Bq m?2) can be expected on stainless steel walls of pools.  相似文献   

6.

Background

Thiazolidinedione is a pentacyclic moiety having five membered unsaturated ring system composed with carbon, oxygen, nitrogen and sulfur molecules at 1 and 3 position of the thiazole ring and widely found throughout nature in various form. They favourably alter concentration of the hormones secreted by adipocytes, particularly adiponectin. They also increase total body fat and have mixed effects on circulating lipids. Thiazolidinedione nucleus is present in numerous biological moieties and has different pharmacological activities likes, e.g. antimalarial, antimicrobial, antimycobacterial, anticonvulsant, antiviral, anticancer, anti-inflammatory, antioxidant, anti-HIV (human immunodeficiency virus) and antituberculosis.

Results and discussion

The synthesized compounds were screened for their in vitro antimicrobial potential against Gram (positive and negative) bacterial and fungal strains by tube dilution technique. In this series, compound 10 exhibited significant antimicrobial activity against B. subtilis and S. aureus with MIC?=?4.2?×?10?2 µM/ml, compound 15 showed significant activity against K. pneumonia with MIC?=?2.60?×?10?2 µM/ml and compound 4 displayed potent antibacterial activity against E. coli with MIC?=?4.5?×?10?2 µM/ml. Compound 10 had most potent antifungal activity against C. albicans and A. niger with MIC?=?4.2?×?10?2 µM/ml. Compounds 12 and 15 were found as most active antidiabetic agents having IC50?=?27.63 μg/ml and 22.35 μg/ml, respectively, using DPPH assay. Antioxidant activity results indicated that compounds 3 and 9 displayed good antioxidant agent with IC50?=?29.04 μg/ml and 27.66 μg/ml respectively, using α amylase assay.

Conclusion

All the synthesized derivatives exhibited good antimicrobial, antidiabetic and antioxidant activities using specific methods then compared with mentioned standard drugs. Especially, compounds 3, 4, 9, 10, 12 and 15 displayed highest activity. Structure activity relationship demonstrated that presence of electron withdrawing group (o-NO2, p-Cl, p-Br) enhanced the antibacterial activity against E. coli as well as increased the antioxidant activity while the presence of electron releasing group (o/p-OCH3, 3,4,5-trimethoxy) enhanced the antibacterial activity against S. aureus, B. subtilis, S. typhi, K. pneumonia, C. albicans and A. niger as well as the antidiabetic activity.
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7.
The enzyme 3-hydroxy-3-methyl-glutaryl CoA reductase (HMGR) is a glycoprotein of the endoplasmic reticulum that participates in the mevalonate pathway, the precursor of cholesterol in human and ergosterol in fungi. This enzyme has three domains: transmembrane, binding, and soluble. In this study, we expressed and purified the soluble fraction of the HMGR enzyme from Candida glabrata (CgHMGR) in an Escherichia coli heterologous system and used it as a model for studying its inhibitory activity. The soluble fraction of CgHMGR was fused to the maltose binding protein (MBP), purified, and characterized. Optimal pH was 8.0, and its optimal temperature activity was 37 °C. The k m and V max for the HMG-CoA were 6.5 μM and 2.26 × 10?3 μM min?1, respectively. Recombinant CgHMGR was inhibited by simvastatin presenting an IC50 at 14.5 μM. In conclusion, our findings suggest that the recombinant HMGR version from C. glabrata may be used as a study model system for HMGR inhibitors such as statins and newly synthesized inhibitor compounds that might be used in the treatment of hypercholesterolemia or mycosis.  相似文献   

8.
The N-(2-pyridyl) 4-toluene sulfonamide as a free ligand (PTS) was prepared from the reaction of 2-amino pyridine and 4-toluenesulfonyl chloride in the presence of potassium hydroxide solution 1 M as a base and THF was used as a solvent. The complex tetrakis [N-(2-pyridyl) sulfonamide] di palladium (1) (Pd2L4) was also prepared from the reaction of PdCl2(CH3CN)2 using (PTS) in the presence of NaOH 0.5 M and its application in Heck and Suzuki reactions. This complex consists of a binuclear unit consisting of four ligands linked to two palladium atoms via the nitrogen of pyridines ring and the nitrogen of sulfonamides. These compounds were confirmed by FT-IR and 1H NMR spectroscopy. Moreover, the structure of the complex was studied by single-crystal X-ray diffraction method. The green crystal of Pd2L4 [L = N-(2-pyridyl) sulfonamide](1) was found to crystallize in the monoclinic space group C2/c with a = 18.2013(19), b = 19.7544(16), c = 17.2898(19) Å, β = 120.179(8) °; V = 5374.0(9) Å3; Z = 4; the final R 1 = 0.0894, wR 2 = 0.1754 (or 5867 observed reflections and 318 variables). The Pd–Pd distance is 2.567(2) Å. In addition, PTS and Pd2L4 presented different antibacterial behaviors. The free ligand was active against Staphylococcus aureus and Escherichia coli, but the complex was inactive against them.  相似文献   

9.
In this study, we cloned a full-length cDNA and the genomic DNA sequence of SmCCoAOMT (GenBank ID JQ007585) from Salvia miltiorrhiza. The 744-bp open-reading frame encodes a protein of 247 amino acids that shares 95 % similarity with one in Vitis vinifera. Real-time quantitative PCR analysis revealed that SmCCoAOMT is most highly expressed in the stems and can be induced by methyl jasmonate (MeJA) and XC-1 treatment. To evaluate its function in vivo, we generated RNA interference transgenic plants through Agrobacterium tumefaciens-mediated gene transfer. Compared with untransformed control plants, the transgenics had significantly less lignin and the expression of lignin-biosynthetic genes SmCCR and SmCOMT was depressed. In 90-day-old roots from plants of transgenic line M5, accumulations of rosmarinic acid and salvianolic acid B (Sal B) were greatly reduced by 0.89- and 0.69-fold, respectively. This low-Sal B phenotype was stable in the roots, with the level of accumulation being approximately 43.58 mg g?1 dry weight, which was 52 % of the amount measured in the untransformed control. Our results suggest that SmCCoAOMT is involved in lignin biosynthesis and affects the accumulation of phenolic acids. This study also provides potential guidance for using lignin-related genes to genetically engineer Salvia miltiorrhiza.  相似文献   

10.
From three cell-associated β-xylosidases produced by Aureobasidium pullulans CBS 135684, the principal enzyme was enriched to apparent homogeneity and found to be active at high temperatures (60–70 °C) over a pH range of 5–9 with a specific activity of 163.3 units (U) mg?1. The enzyme was thermostable, retaining over 80% of its initial activity after a 12-h incubation at 60 °C, with half-lives of 38, 22, and 10 h at 60, 65, and 70 °C, respectively. Moreover, it was tolerant to xylose inhibition with a K i value of 18 mM. The K m and V max values against p-nitrophenyl-β-d-xylopyranoside were 5.57 ± 0.27 mM and 137.0 ± 4.8 μmol min?1 mg?1 protein, respectively. When combining this β-xylosidase with xylanase from the same A. pullulans strain, the rate of black liquor xylan hydrolysis was significantly improved by up to 1.6-fold. The maximum xylose yield (0.812 ± 0.015 g g?1 dry weight) was obtained from a reaction mixture containing 10% (w/v) black liquor xylan, 6 U g?1 β-xylosidase and 16 U g?1 xylanase after incubation for 4 h at 70 °C and pH 6.0.  相似文献   

11.
A novel cyclopropane derivative, 1-cyano-N-p-tolylcyclopropanecarboxamide (C12H12N2O, Mr = 200.24) was synthesized and its structure was studied by X-ray diffraction, FTIR, 1H and 13C NMR spectrum and MS. The crystals are monoclinic, space group P2_1/c with a = 7.109 (4), b = 13.758 (7), c = 11.505 (6) Å, α = 90.00, β = 102.731 (8), γ = 90.00 °, V = 1097.6 (9) Å3, Z = 4, F(000) = 312, D c  = 1.212 g/cm3, μ = 0.0800 mm?1, the final R = 0.0490 and wR = 0.1480 for 1,375 observed reflections with I > 2σ(I). A total of 6,109 reflections were collected, of which 2,290 were independent (R int = 0.0290). Theoretical calculation of the title compound was carried out with HF/6-31G (d,p), B3LYP/6-31G (d,p), MP2/6-31G (d,p). The full geometry optimization was carried out using 6-31G(d,p) basis set, and the frontier orbital energy. Atomic net charges were discussed, and the structure-activity relationship was also studied. The preliminary biological test showed that the synthesized compound is bioactive against the KARI of Escherichia coli.  相似文献   

12.
Peucedanum alsaticum L. and Peucedanum cervaria (L.) Lap. are, in common with all species belonging to the Apiaceae family, rich in coumarins and essential oils. Phenolic acids also present in the plant are very important pharmacologically, because of their broad spectrum of biological activity. A simple high-performance liquid chromatographic method has been developed for separation and quantitative analysis of the major phenolic acids in extracts obtained from the fruits of P. alsaticum and P. cervaria. Soxhlet extraction, ultrasound extraction, and accelerated solvent extraction under different conditions were used to find the most efficient extraction conditions. Optimum chromatographic performance was obtained with a C18 column and acetonitrile—1% (v/v) aqueous acetic acid as mobile phase. Ferulic, p-coumaric, caffeic, vanillic, syringic, p-hydroxybenzoic, protocatechuic, chlorogenic, and gallic acids were investigated in the fruits of the plants. For all calibration plots linearity was good (R 2 > 0.9991) in the ranges tested. The highest yields of most of the phenolic acids were achieved by use of accelerated solvent extraction. The predominant phenolic acid in the fruits of both plants was chlorogenic acid. The amounts, which depended on the method of extraction, were approximately 146 ± 1.616 and 109.92 ± 3.405 mg per 100 g dry weight for P. cervaria and P. alsaticum, respectively.  相似文献   

13.
We report herein one of our recent studies on nanostructured ZnO electrodes for application in dye-sensitized solar cells, focusing on achieving a higher open-circuit voltage (VOC). ZnO films were obtained through solution-processed routes including pyrolytic conversion of layered hydroxide zinc acetate (LHZA) films deposited on a fluorine-doped tin oxide-coated conducting glass substrate by a chemical bath deposition method. The morphology of the initial LHZA and the converted ZnO films was tuned from a thick (approximately 12 μm) flower bed-/lawn-like bilayer structure to a thin (1.2 μm) lawn-like quasi-monolayer structure by decreasing the Zn source concentration in the chemical bath. VOC was found to be enhanced with this morphological change from 0.692 (the bilayer structure) to 0.735 V (the quasi-monolayer structure). Fine tuning of the quasi-monolayer structure by introducing the grain growth effect led to VOC of the cell as high as 0.807 V, although a short-circuit photocurrent density (JSC) remained low. Further attempts were then made to increase JSC while maintaining the high VOC. When the thickness of the lawn-like monolayer film was increased up to approximately 5 μm, the resultant cell showed VOC?=?0.750 V, JSC?=?6.20 mA cm?2 and a conversion efficiency (η) of 2.83%. The film with a modified flower bed-/lawn-like bilayer structure approximately 11 μm in thickness finally yielded VOC?=?0.741 V, JSC?=?13.6 mA cm?2, and η?=?5.44%.  相似文献   

14.
Three bacterial isolates, GT2, GT3, and GT7, were isolated from the sludge and water of a circulating cooling system of iron and steel plant by screening on Cr(VI)-containing plates. Three isolates were characterized as the members of the genus Pseudomonas on the basis of phenotypic characteristics and 16S rRNA sequence analysis. All isolates were capable of resisting multiple antibiotics and heavy metals. GT7 was most resistant to Cr(VI), with a minimum inhibitory concentration (MIC) of 6.5 mmol L?1. GT7 displayed varied rates of Cr(VI) reduction in M2 broth, which was dependent on pH, initial Cr(VI) concentration, and inoculating dose. Total chromium analysis revealed that GT7 could remove a part of chromium from the media, and the maximum rate of chromium removal was up to 40.8 %. The Cr(VI) reductase activity of GT7 was mainly associated with the soluble fraction of cell-free extracts and reached optimum at pH 6.0~8.0. The reductase activity was apparently enhanced by external electron donors and Cu(II), whereas it was seriously inhibited by Hg(II), Cd(II), and Zn(II). The reductase showed a K m of 74 μmol L?1 of Cr(VI) and a V max of 0.86 μmol of Cr(VI) min?1 mg?1 of protein. The results suggested that GT7 could be a promising candidate for in situ bioremediation of Cr(VI).  相似文献   

15.
16.
Interaction of two mononuclear tetracoordinate complexes [Co(dmphen)Br2] and [Co(dmphen)I2] (dmphen = 2,9-dimethyl-1,10-phenanthroline), which have been recently reported to behave as single-molecule magnets (SMMs) in an applied external field, with calf thymus (CT) DNA in solution was studied by spectral methods (UV–Vis, fluorescence, and circular dichroism). Results indicate that both complexes along with their chlorido analogue [Co(dmphen)Cl2] are able to bind with the CT DNA via intercalation, with the values of Stern–Volmer constants obtained from the linear quenching plot in range of 1.86 × 104–2.11 × 104 M?1. Furthermore, Topoisomerase I inhibition studies suggest that all three complexes exhibit inhibition activity at concentrations of 45 μM.  相似文献   

17.
18.
Structure and dynamics of a free aquaporin (AQP1) are studied by a coarse-grained Monte Carlo simulation as a function of temperature using a phenomenological potential with the input of a knowledge-based residue–residue interaction. Response of the radius of gyration (R g) of the protein to the temperature (T) is found to be nonlinear: Decay of R g at T ≤ T c is followed by a continuous increase at T ≥ T c before reaching its saturation. In thermo-responsive regime, the protein exhibits segmental globularization with the persistence of three regions along its sequence involving residues 1M–25V and 250V–269K toward the beginning and end segments with a narrow intermediate region around 155A–163D. A detail analysis of the structure factor S(q) shows a global random coil conformation at high temperatures with an effective dimension D e ~ 1.74 and a globular structure (D e ~ 3) at low temperatures. In thermo-responsive regime, the variation of S(q) with the wave vector q reveals a systematic redistribution of self-organizing residues (in globular and fibrous sections) that depends on the length scale and the temperature.  相似文献   

19.
The crystal structures of four organoselenium compounds, viz. bis(2-formylphenyl)diselenide (5), bis(2-methylnaphthyl)diselenide (6), organoselenenyl sulfide (7), and spiroselenurane (8) are described. Crystal data for 5: space group Pca21, crystal system orthorhombic, a=7.9969(4) Å, b=20.8794(12) Å, c=15.8307(13) Å, Z=8, R=0.0292. Owing to the presence of a strong Se···O interaction in compound 5 the geometry around the selenium atom may be considered as T-shaped. Crystal data for 6: space group Pna21, crystal system orthorhombic, a=18.2253(12) Å, b=13.0714(8) Å, c=7.7355(5) Å, Z=4, R=0.0570. The molecule has a cisoid conformation. Crystal data for 7: space group Pbcn, crystal system orthorhombic, a=22.2144(13) Å, b=8.0255(4) Å, c=15.4496(9) Å, Z=8, R=0.0292. Due to intramolecular Se···N interaction in 7 the geometry around selenium is T- shaped. Crystal data for 8: space group P21/c, crystal system monoclinic, a=7.4585(5) Å, b=19.5634(13) Å, c=8.0428(5) Å, β=97.1320(10)°, Z=4, R=0.0254. The O?Se?O angle is 172.86(6)°.  相似文献   

20.
A novel bis-heterocyclic compound was synthesized and characterized. The crystal structure of the title compound (C22H20ClN5OS, Mr = 437.94) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P-1 with a = 8.646 (2), b = 9.148 (3), c = 14.540 (4) Å, α = 94.422 (4), β = 98.500 (4), γ = 102.823 (4)°, V = 1101.8 (5) Å3, Z = 2, F(000) = 312, Dc = 1.320 g/cm3, μ = 0.2900 mm?1, the final R 1 = 0.041000 and wR 2 = 0.1160 for 2675 observed reflections with I > 2σ(I). A total of 5623 reflections were collected, of which 3866 were independent (R int = 0.019000). The fungicidal activity of title compound was determined, the results showed the title compound displayed moderate fungicidal activity against G. zeae Petch, Phytophthora infestans (Mont.) de Bary, Botryosphaeria berengeriana f. sp. piricola (Nose) koganezawa et Sakuma, Fusarium oxysporum f.sp. cucumerinum, and Cercospora arachidicola.  相似文献   

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