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Sumaira Mehboob Nasir Ahmad Naeem Rashid Tadayuki Imanaka Muhammad Akhtar 《Extremophiles : life under extreme conditions》2016,20(4):559-566
Genome sequence of hyperthermophilic archaeon Pyrobaculum calidifontis revealed the presence of an open reading frame, Pcal_0768, corresponding to a putative 4-α-glucanotranferase belonging to glycoside hydrolases (GH) family 77. We have produced, in Escherichia coli, and purified recombinant Pcal_0768 which exhibited high disproportionation (690 U mg?1) activity. To the best of our knowledge, this is the highest ever reported activity for any member of family GH77. Maltooligosaccharides, when used as sole substrates, were disproportionated into linear maltooligohomologues. The analysis of the reaction end products revealed no evidence for the production of cycloamyloses. Catalytic activity of the enzyme remained unchanged in the presence or the absence of ionic and nonionic detergents. γ-cyclodextrin, an inhibitor of 4-α-glucanotransferases, did not show any inhibitory effect on Pcal_0768 activity. These properties make Pcal_0768 a potential candidate for starch processing industry. 相似文献
864.
Muhammad Riaz Yotam Raz Maaike van Putten Guillem Paniagua-Soriano Yvonne D. Krom Bogdan I. Florea Vered Raz 《PLoS genetics》2016,12(5)
Poly(A) Binding Protein Nuclear 1 (PABPN1) is a multifunctional regulator of mRNA processing, and its expression levels specifically decline in aging muscles. An expansion mutation in PABPN1 is the genetic cause of oculopharyngeal muscle dystrophy (OPMD), a late onset and rare myopathy. Moreover, reduced PABPN1 expression correlates with symptom manifestation in OPMD. PABPN1 regulates alternative polyadenylation site (PAS) utilization. However, the impact of PAS utilization on cell and tissue function is poorly understood. We hypothesized that altered PABPN1 expression levels is an underlying cause of muscle wasting. To test this, we stably down-regulated PABPN1 in mouse tibialis anterior (TA) muscles by localized injection of adeno-associated viruses expressing shRNA to PABPN1 (shPab). We found that a mild reduction in PABPN1 levels causes muscle pathology including myofiber atrophy, thickening of extracellular matrix and myofiber-type transition. Moreover, reduced PABPN1 levels caused a consistent decline in distal PAS utilization in the 3’-UTR of a subset of OPMD-dysregulated genes. This alternative PAS utilization led to up-regulation of Atrogin-1, a key muscle atrophy regulator, but down regulation of proteasomal genes. Additionally reduced PABPN1 levels caused a reduction in proteasomal activity, and transition in MyHC isotope expression pattern in myofibers. We suggest that PABPN1-mediated alternative PAS utilization plays a central role in aging-associated muscle wasting. 相似文献
865.
Ishfaq A. Sheikh Muhammad Yasir Muhammad Abu-Elmagd Tanveer A. Dar Adel M. Abuzenadah Ghazi A. Damanhouri Mohammed Al-Qahtani Mohd A. Beg 《BMC structural biology》2016,16(1):15
Background
Currently, alternate plasticizers are used to replace phthalate plasticizers in children’s toys, medical equipments and food packaging, due to the adverse effects of phthalate compounds on human health and laws prohibiting their use. Current information regarding the safety and potential adverse effects of alternate plasticizers is limited and recent studies have found alternate plasticizers to display similar characteristics to those observed in phthalate plasticizers. This study was undertaken to evaluate and predict the potential endocrine disrupting activity of the three most commonly used alternate plasticizers: di(2-ethylhexyl)terephthalate (DEHT), tris(2-ethylhexyl)trimellitate (TOTM), and diisononyl hexahydrophthalate (DINCH) against human sex hormone-binding globulin (SHBG) using in silico approaches.Materials and methods
The crystal structure of human SHBG (Id: 1D2S) was retrieved from Protein Data Bank. PubChem database was searched for the structures of alternate plasticizers, DEHT, TOTM, and DINCH. Docking was performed using Glide (Schrodinger) Induced Fit Docking module.Results
Induced Fit Docking of three alternate plasticizer compounds indicated that each of the three compounds fitted well into the steroid binding pocket of SHBG. Docking displays showed interactions of alternate plasticizers with 25–30 amino-acid residues of SHBG; 18–20 amino residues overlapped between the natural ligand, DHT, and the three compounds (commonality of 82–91 %). The hydrogen-bonding interaction of the amino-acid residue, Asn-82, of SHBG was also present in displays of DHT and all the three alternate phthalates. The binding affinity of all the three alternate phthalates was higher than DHT; maximum in DINCH followed by TOTM and DEHT.Conclusion
Our results suggested that the three alternate plasticizers have potential to engage the important interacting residues of SHBG and thus interfere in its steroid homeostatic function.866.
Rashad?Mukhatar?BalalEmail author Muhammad?Adnan?Shahid Muhammad?Mansoor?Javaid Zafar?Iqbal Muhammad?Akbar?Anjum Francisco?Garcia-Sanchez Neil?Scott?Mattson 《Acta Physiologiae Plantarum》2016,38(6):158
High temperature is an environmental stress which destroys agricultural crops and inhibits their growth and productivity. The aim of current investigation was to examine the role of selenium (Se) on cucumber (Cucumis sativus L.) cv. Sahil plant growth, physio-biochemical and yield attributes under heat stress (HS) in controlled conditions. Plants were grown under normal temperature (NT; 28/18 °C day/night) from sowing to 32 days after sowing (DAS). All plants were foliar-sprayed with Se (8 µM) at flower-initiation stage (32-DAS) and heat stress (HS; 40/30 °C day/night) was induced from 35-DAS to entire duration of the experiment (75-DAS). Data regarding growth, physio-biochemical and yield traits were measured. Heat stress decreased growth traits, total chlorophyll contents, chlorophyll fluorescence parameters, photosynthesis (Pn), stomatal conductance (g s), transpiration rate (E), antioxidant enzyme activities, membrane stability index (MSI) and yield-related attributes, while increased intercellular CO2 (Ci), ROS production, lipid peroxidation (LPO), non-photochemical quenching (NPQ) and compatible solutes. Exogenous application of Se mitigated HS-induced injurious effects by improving growth components, Pn, g s, E, chlorophyll content, chlorophyll fluorescence parameters, antioxidant enzyme activities, level of osmolytes, MSI and yield attributes and reducing ROS, LPO and NPQ. Selenium reversed heat-induced oxidative damage by strengthening antioxidative mechanism, which resulted in higher scavenging of ROS, thereby minimizing LPO. It is suggested that Se-induced improvement in Pn, growth and productivity associated traits under HS is linked with enhanced antioxidant activities and osmolytes accumulation. In addition, Se applied at flower initiation is highly effective in alleviating heat damage in cucumber. 相似文献
867.
Shafaqat Ali Muhammad Rizwan Najeeb Ullah Saima Aslam Bharwana Muhammad Waseem Muhammad Ahsan Farooq Ghulam Hasan Abbasi Mujahid Farid 《Acta Physiologiae Plantarum》2016,38(11):262
Accumulation of excess copper (Cu) in agricultural soils can decrease growth and quality of crops grown on these soils and a little information is available on the role of silicon (Si) in reducing Cu toxicity in plants. A hydroponic study was conducted to investigate the effects of Si (1.0 mM) on growth and physiology of cotton seedlings grown on different Cu (0, 25, and 50 µM) concentrations. Elevated levels of Cu decreased growth, biomass, photosynthetic pigments, and gas exchange characteristics, and increased the electrolyte leakage (EL), hydrogen peroxide (H2O2), and thiobarbituric acid reactive substances (TBARS) contents in leaf, stem, and roots of cotton seedlings. Cu stress alone decreased the activities of key antioxidant enzymes in cotton seedlings. Exogenous application of Si alleviated the toxic effects of Cu on cotton seedlings by improving growth, photosynthetic pigments, and gas exchange characteristics under Cu stress. The Si application decreased Cu concentrations in leaves, stem, and roots as compared with the control plants. Furthermore, Si decreased oxidative stress as evidenced by decreased EL, H2O2, and TBARS contents, and increased the antioxidant enzyme activities in cotton seedlings. This study provides evidences of Si-mediated reduction of Cu toxicity in cotton seedlings at physiological and biochemical levels. 相似文献
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869.
Anning Li Yue Wu Jenny Linnoila Benjamin Pulli Cuihua Wang Matthias Zeller Muhammad Ali Grant K. Lewandrowski Jinghui Li Benoit Tricot Edmund Keliher Gregory R. Wojtkiewicz Giulia Fulci Xiaoyuan Feng Bakhos A. Tannous Zhenwei Yao John W. Chen 《Cancer immunology, immunotherapy : CII》2016,65(12):1545-1554
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