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21.
Zhongyuan Ren Le Duy Do Géraldine Bechkoff Saida Mebarek Nermin Keloglu Saandia Ahamada Saurabh Meena David Magne Slawomir Pikula Yuqing Wu René Buchet 《PloS one》2015,10(3)
A direct and continuous approach to determine simultaneously protein and phosphate concentrations in cells and kinetics of phosphate release from physiological substrates by cells without any labeling has been developed. Among the enzymes having a phosphatase activity, tissue non-specific alkaline phosphatase (TNAP) performs indispensable, multiple functions in humans. It is expressed in numerous tissues with high levels detected in bones, liver and neurons. It is absolutely required for bone mineralization and also necessary for neurotransmitter synthesis. We provided the proof of concept that infrared spectroscopy is a reliable assay to determine a phosphatase activity in the osteoblasts. For the first time, an overall specific phosphatase activity in cells was determined in a single step by measuring simultaneously protein and substrate concentrations. We found specific activities in osteoblast like cells amounting to 116 ± 13 nmol min-1 mg-1 for PPi, to 56 ± 11 nmol min-1 mg-1 for AMP, to 79 ± 23 nmol min-1 mg-1 for beta-glycerophosphate and to 73 ± 15 nmol min-1 mg-1 for 1-alpha-D glucose phosphate. The assay was also effective to monitor phosphatase activity in primary osteoblasts and in matrix vesicles. The use of levamisole – a TNAP inhibitor- served to demonstrate that a part of the phosphatase activity originated from this enzyme. An IC50 value of 1.16 ± 0.03 mM was obtained for the inhibition of phosphatase activity of levamisole in osteoblast like cells. The infrared assay could be extended to determine any type of phosphatase activity in other cells. It may serve as a metabolomic tool to monitor an overall phosphatase activity including acid phosphatases or other related enzymes. 相似文献
22.
R Gon?alves LA Szmuchrowski LS Prado BP Couto JCQ Machado VO Damasceno JA Lamounier 《Biology of sport / Institute of Sport》2015,32(3):255-260
The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. 相似文献
23.
Elroy J. Pereira Suzana Fonseca Ram M. Meena Nagappa Ramaiah 《Indian journal of microbiology》2017,57(4):400-408
Marine bacteria possess a wide variety of bioremediation potential which is beneficial environmentally and economically. In this study, bacterial isolates from marine waters were screened for tolerance and growth in high concentrations of chromate (Cr6+). Two isolates, capable of tolerating Cr6+ concentrations 300 µg mL?1 or higher, and found to completely reduce 20 µg mL?1 Cr6+ were grown in Cr6+ (50 and 100 mg kg?1) spiked garden soil. Notably, both facilitated normal germination and growth of mung (Vigna radiata) seeds, which could hardly germinate in Cr6+ spiked garden soil without either of these bacteria. In fact, large percent of mung seeds failed to sprout in the Cr6+ spiked garden soil and could not grow any further. Apparently, chromate detoxification by marine bacterial isolates and the ability of mung plants to deal with the reduced form appear to work complementarily. This study provides an insight into marine bacterial abilities with respect to chromium and potential applications in promoting growth of leguminous plants-similar to mung in particular-in Cr6+ contaminated soil. 相似文献
24.
Mukesh Meena Prashant Swapnil Andleeb Zehra Manish Kumar Dubey R. S. Upadhyay 《Archives Of Phytopathology And Plant Protection》2017,50(13-14):629-648
Trichoderma spp. are well-known biological agents that have significant antagonistic activity against several plant pathogenic fungi. In the present study, Trichoderma spp. were tested in vitro for their antagonistic activity against different spp. of Fusarium and Alternaria viz. Alternaria alternata, A. brassicae, A. solani, Fusarium oxysporum and F. solani using dual plate assay and by the production of volatile and non-volatile compounds. The results obtained revealed that Trichoderma harzianum and T. viride effectively inhibited the growth and spore production of different spp. of Fusarium and Alternaria. The highest growth inhibition was found in A. alternata 62.50% and 60.00% by non-volatile compounds of T. harzianum and T. viride, respectively. Similarly, the volatile compounds inhibit the maximum growth of A. alternata 40.00% and 35.00% by T. harzianum and T. viride, respectively. Volatile and non-volatile compounds of Trichoderma spp. were analysed by GC-MS technique and the properties of distinguished compounds showed antifungal, antimicrobial and antibiotic activities. Volatile compounds of T. harzianum and T. viride showed highest percent abundance for glacial acetic acid (45.32%) and propyl-benzene (41.75%), respectively. In case of non-volatile compounds, T. harzianum and T. viride showed D-Glucose, 6-O-α-D-galactopyranosyl- (38.45%) and 17-Octadecynoic acid (36.23%), respectively. The results of present study confirmed that T. harzianum can be used as a promising biological control agent against Alternaria and Fusarium spp. that cause diseases in various vegetables and crops. 相似文献
25.
Mukesh Meena Andleeb Zehra Prashant Swapnil Manish Kumar Dubey Chandra Bali Patel R. S. Upadhyay 《Archives Of Phytopathology And Plant Protection》2017,50(7-8):317-329
Tomato is considered as one of the most important sources of nutrients such as lycopene, β-carotene, flavonoids, ascorbic acid (vitamin C) and hydroxyl-cinnamic acid derivatives. The quality and quantity of nutrients in tomato fruits were decreased during the severe infection of Alternaria alternata. The present study deals with the estimation of lycopene, β-carotene, phenolic and ascorbic acid content in tomato fruits which were infected with A. alternata and its toxins such as tenuazonic acid (TeA), alternariol (AOH) and alternariol monomethyl ether (AME). The lycopene, β-carotene, ascorbic acid and phenolic content were found lowest in pathogen-infected fruits i.e. (0.66 ± 0.03 mg/g), (0.14 ± 0.01 mg/g), (1.89 ± 0.2 mg/g) and (0.58 ± 0.05 mg/g), respectively, followed by toxins-treated samples as compared to the control. The results concluded that A. alternata mostly affects the nutritional values of tomato fruits due to the combined effect of the toxins. 相似文献
26.
Chandan Shee Saurabh Agarwal Deepankar Gahloth Kalpana Meena Ashwani K. Sharma 《Journal of plant biochemistry and biotechnology.》2009,18(1):101-104
A low molecular mass peptide like compound with antimicrobial and trypsin inhibitory activity was isolated from the seeds of Lagenaria siceraria. It was purified by ion-exchange and reverse-phase chromatography. The molecular weight of the compound was 678.9 Dalton as determined by MALDI-MS. The infra-red absorbance at 1639 cm?1, characteristic of an amide bond, by FTIR spectroscopic studies, and absorption at 214 nm on spectrophotometer indicates the peptidic nature of the compound. The compound exhibited antimicrobial activity when tested against Escherichia coli with minimum inhibitory concentration of 20 μM, and trypsin inhibitory activity inhibiting trypsin at a molar ratio of 1:2. 相似文献
27.
G. Sridevi N. Sabapathi P. Meena R. Nandakumar R. Samiyappan S. Muthukrishnan K. Veluthambi 《Journal of plant biochemistry and biotechnology.》2003,12(2):93-101
Agrobacterium-mediated transformation of an elite indica rice variety, Pusa Basmati 1, was performed using LBA4404 (pSB1, pMKU-RF2) that harbours a rice chitinase gene (chi11) under the control of the maize ubiquitin (Ubi1) promoter-intron. Right border (gus) and left border (hph) flanking sequences and the transgene (chi11) in the middle of the T-DNA were used as probes in Southern analysis. Out of eleven independent T0 plants regenerated, three had single copy T-DNA insertions and eight had multiple T-DNA insertions. Nine T0 plants carried the complete T-DNA with the chitinase transgene. Two T0 plants did not carry chi11, though they had other T-DNA portions. Three plants harbouring single copy insertions and one plant harbouring two inserted copies were analyzed in detail. A segregation ratio of 3:1, reflecting T-DNA insertion at a single locus, was observed in the progeny of all the four T0 plants. Northern and western blot analyses of T1 plants revealed constitutive expression of chitinase at high levels. Bioassays of T1 plants indicated enhanced resistance to the sheath blight pathogen, Rhizoctonia solani, in comparison to control plants. A homozygous transgenic line was established from one T0 line, which exhibited the maximum resistance to R. solani. 相似文献
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30.
Renu Pandey Surendra Kumar Meena Vengavasi Krishnapriya Altaf Ahmad Naval Kishora 《Plant cell reports》2014,33(6):919-928