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https://www.readbyqxmd.com/read/28316047/exogenous-application-of-plant-growth-regulators-pgrs-induces-chilling-tolerance-in-short-duration-hybrid-maize
#1
Muhammad Ahmed Waqas, Imran Khan, Muhammad Javaid Akhter, Mehmood Ali Noor, Umair Ashraf
Chilling stress hampers the optimal performance of maize under field conditions precipitously by inducing oxidative stress. To confer the damaging effects of chilling stress, the present study aimed to investigate the effects of some natural and synthetic plant growth regulators, i.e., salicylic acid (SA), thiourea (TU), sorghum water extract (SWE), and moringa leaf extract (MLE) on chilling stress tolerance in autumn maize hybrid. Foliar application of growth regulators at low concentrations was carried out at six leaf (V6) and tasseling stages...
March 18, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28315928/boosting-the-growth-of-the-probiotic-strain-lactobacillus-paracasei-ssp-paracasei-f19
#2
Desideria Brignone, Pia Radmann, Jürgen Behr, Rudi F Vogel
Single so-called booster substances were added to the fermentation medium of the probiotic strain Lactobacillus (L.) paracasei ssp. paracasei F19 to enhance its growth. A wide screening was carried out in microtiter plates and a statistical analysis of the growth parameters was performed. CFU counts were used to correlate the increase in OD590nm with the increase in viable cell number. Sodium ascorbate, sodium pyruvate, manganese sulfate and cysteine had a remarkable boosting effect on the growth of L. paracasei F19...
March 18, 2017: Archives of Microbiology
https://www.readbyqxmd.com/read/28293865/the-inhibition-effect-of-lactobacilli-against-growth-and-biofilm-formation-of-pseudomonas-aeruginosa
#3
Dariush Shokri, Mohammad Rabbani Khorasgani, Milad Mohkam, Seyed Masih Fatemi, Younes Ghasemi, Asghar Taheri-Kafrani
The emergence of antibiotic-resistant and food-spoilage microorganisms has renewed efforts to identify safe and natural alternative agents of antibiotics such as probiotics. The aim of this study was the isolation of lactobacilli as potential probiotics from local dairy products with broad antibacterial and anti-biofilm activities against antibiotic-resistant strains of Pseudomonas aeruginosa and determination of their inhibition mechanism. Antibiotic susceptibility and classification of acquired resistance profiles of 80 P...
March 14, 2017: Probiotics and Antimicrobial Proteins
https://www.readbyqxmd.com/read/28293217/mechanistic-insights-underlying-tolerance-to-acetic-acid-stress-in-vaginal-candida-glabrata-clinical-isolates
#4
Diana V Cunha, Sara B Salazar, Maria M Lopes, Nuno P Mira
During colonization of the vaginal tract Candida glabrata cells are challenged with the presence of acetic acid at a low pH, specially when dysbiosis occurs. To avoid exclusion from this niche C. glabrata cells are expected to evolve efficient adaptive responses to cope with this stress; however, these responses remain largely uncharacterized, especially in vaginal strains. In this work a cohort of 18 vaginal strains and 2 laboratory strains (CBS138 and KUE100) were phenotyped for their tolerance against inhibitory concentrations of acetic acid at pH 4...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28285657/two-component-regulatory-system-acts-actr-is-required-for-sinorhizobium-meliloti-adaptation-to-oxidative-stress
#5
Guirong Tang, Sunjun Wang, Dawei Lu, Leqi Huang, Ningning Li, Li Luo
The two-component system ActS/ActR plays important roles in bacterial adaptation to abiotic stress, including acid tolerance and oxidant resistance. However, the underlying regulatory mechanism is not clear. In this study, we found that the ActS/ActR system is required for adaptation to oxidative stress by regulating the transcription of the genes actR, katB, gshA and gshB1. The actS and actR mutants were sensitive to low pH and oxidants such as H2O2, oxidized glutathione (GSSG) and sodium nitroprusside (SNP)...
May 2017: Microbiological Research
https://www.readbyqxmd.com/read/28278249/expression-of-c-5-sterol-desaturase-from-an-edible-mushroom-in-fisson-yeast-enhances-its-ethanol-and-thermotolerance
#6
Ayushi Kamthan, Mohan Kamthan, Asis Datta
Bioethanol is an environment friendly and renewable source of energy produced by the fermentation of agricultural raw material by a variety of microorganisms including yeast. Obtaining yeast strains that are tolerant to stresses like high levels of ethanol and high temperature is highly desirable as it reduces cost and increases yield during bioethanol production. Here, we report that heterologous expression of C-5 Sterol desaturase (FvC5SD)-an ergosterol biosynthesis enzyme from an edible mushroom Flammulina velutipes in fission yeast, not only imparts increased thermotolerance but also tolerance towards high ethanol concentration and low pH...
2017: PloS One
https://www.readbyqxmd.com/read/28270819/effects-of-low-ph-on-photosynthesis-related-physiological-parameters-and-nutrient-profiles-of-citrus
#7
An Long, Jiang Zhang, Lin-Tong Yang, Xin Ye, Ning-Wei Lai, Ling-Ling Tan, Dan Lin, Li-Song Chen
Seedlings of "Xuegan" (Citrus sinensis) and "Sour pummelo" (Citrus grandis) were irrigated daily with a nutrient solution at a pH of 2.5, 3, 4, 5, or 6 for 9 months. Thereafter, the following responses were investigated: seedling growth; root, stem, and leaf concentrations of nutrient elements; leaf gas exchange, pigment concentration, ribulose-1,5-bisphosphate carboxylase/oxygenase activity and chlorophyll a fluorescence; relative water content, total soluble protein level, H2O2 production and electrolyte leakage in roots and leaves...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28265263/genome-sequence-of-desulfurella-amilsii-strain-tr1-and-comparative-genomics-of-desulfurellaceae-family
#8
Anna P Florentino, Alfons J M Stams, Irene Sánchez-Andrea
The acidotolerant sulfur reducer Desulfurella amilsii was isolated from sediments of Tinto River, an extremely acidic environment. Its ability to grow in a broad range of pH and to tolerate certain heavy metals offers potential for metal recovery processes. Here we report its high-quality draft genome sequence and compare it to the available genome sequences of other members of Desulfurellaceae family: D. acetivorans. D. multipotens, Hippea maritima. H. alviniae, H. medeae, and H. jasoniae. For most species, pairwise comparisons for average nucleotide identity (ANI) and in silico DNA-DNA hybridization (DDH) revealed ANI values from 67...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28261538/efficient-expression-of-sortase-a-from-staphylococcus-aureus-in-escherichia-coli-and-its-enzymatic-characterizations
#9
Zhimeng Wu, Haofei Hong, Xinrui Zhao, Xun Wang
BACKGROUND: Sortase A (SrtA) is a transpeptidase found in Staphylococcus aureus, which is widely used in site-specific protein modification. However, SrtA was expressed in Escherichia coli (E. coli) in rather low level (ranging from several milligrams to 76.9 mg/L at most). The present study aims to optimize fermentation conditions for improving SrtA expression in E. coli. RESULTS: Under the optimized media (0.48 g/L glycerol, 1.37 g/L tryptone, 0.51 g/L yeast extract, MOPS 0...
2017: Bioresources and Bioprocessing
https://www.readbyqxmd.com/read/28253999/isolation-characterization-and-evaluation-of-the-probiotic-potential-of-a-novel-lactobacillus-strain-isolated-from-feta-type-cheese
#10
Stavros Plessas, Chrysanthi Nouska, Athanasios Karapetsas, Stavros Kazakos, Athanasios Alexopoulos, Ioanna Mantzourani, Pelagia Chondrou, Maria Fournomiti, Alex Galanis, Eugenia Bezirtzoglou
In the present study 45 lactic acid bacteria (LAB) strains were isolated from Feta-type cheese and were screened for probiotic potential in a series of established in vitro tests, including resistance to low pH, resistance to pepsin and pancreatin and tolerance to bile salts. The strain K5, which displayed properties similar to or even better than the reference strain Lactobacillus plantarum ATCC 14917, was chosen for further analysis. Firstly, multiplex PCR analysis indicated that the novel strain belongs to the paracasei species...
July 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28250175/intertidal-oysters-reach-their-physiological-limit-in-a-future-high-co2-world
#11
Elliot Scanes, Laura M Parker, Wayne A O'Connor, Laura S Stapp, Pauline M Ross
Sessile marine molluscs living in the intertidal zone experience periods of internal acidosis when exposed to air (emersion) during low tide. Relative to other marine organisms, molluscs have been identified as vulnerable to future ocean acidification; however, paradoxically it has also been shown that molluscs exposed to high CO2 environments are more resilient compared with those molluscs naive to CO2 exposure. Two competing hypotheses were tested using a novel experimental design incorporating tidal simulations to predict the future intertidal limit of oysters in a high-CO2 world; either high-shore oysters will be more tolerant of elevated PCO2 because of their regular acidosis, or elevated PCO2  will cause high-shore oysters to reach their limit...
March 1, 2017: Journal of Experimental Biology
https://www.readbyqxmd.com/read/28242427/purification-and-characterization-of-a-collagenase-from-penicillium-sp-ucp-1286-by-polyethylene-glycol-phosphate-aqueous-two-phase-system
#12
Maria Carolina de Albuquerque Wanderley, José Manoel Wanderley Duarte Neto, Wendell Wagner Campos Albuquerque, Daniela de Araújo Viana Marques, Carolina de Albuquerque Lima, Sara Isabel da Cruz Silvério, José Luiz de Lima Filho, José António Couto Teixeira, Ana Lúcia Figueiredo Porto
Collagenases are proteolytic enzymes capable of degrading both native and denatured collagen, reported to be applied in industrial, medical and biotechnological sectors. Liquid-liquid extraction using aqueous two-phase system (ATPS) is one of the most promising bioseparation techniques, which can substitute difficult solid-liquid separation processes, offering many advantages over conventional methods including low-processing time, low-cost material and low-energy consumption. The collagenase produced by Penicillium sp...
February 24, 2017: Protein Expression and Purification
https://www.readbyqxmd.com/read/28238432/impact-of-irrigation-based-sugarcane-cultivation-on-the-chiredzi-and-runde-rivers-quality-zimbabwe
#13
Tamuka Nhiwatiwa, Tatenda Dalu, Luc Brendonck
Agriculture is vital in sustaining human livelihoods. However, agriculture as it is currently practiced, is contributing to the degradation of freshwater ecosystems globally. We investigated impacts of irrigation return flows from sugarcane farming on water quality and health status of the Chiredzi and Runde Rivers, a biodiversity hotspot region in south-eastern Lowveld of Zimbabwe. The water quality at inlets from the crop field into the wetland system; wetland outlets into the river systems; and river sites upstream and downstream of wetland outlets were monitored during the dry and wet seasons...
February 23, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28235561/physiological-and-comparative-genomic-analysis-of-acidithiobacillus-ferrivorans-pq33-provides-psychrotolerant-fitness-evidence-for-oxidation-at-low-temperature
#14
Robert Ccorahua-Santo, Anika Eca, Michel Abanto, Gregory Guerra, Pablo Ramírez
Friendly environmental hydrometallurgy at low temperatures is principally promoted by Acidithiobacillus ferrivorans. Until recently, the synergy between cold tolerance and the molecular mechanism of ferrous iron (Fe(2+)) oxidation was unknown. In the present paper, we conducted a physiological and comparative genomics analysis of the new strain A. ferrivorans PQ33 to elucidate the oxidation mechanism at low temperatures, with emphasis placed on trehalose and the Rus operon. PQ33 exhibited a doubling time of 66...
February 21, 2017: Research in Microbiology
https://www.readbyqxmd.com/read/28221886/technological-properties-and-biogenic-amines-production-by-bacteriocinogenic-lactococci-and-enterococci-strains-isolated-from-raw-goat-s-milk
#15
Luana Martins Perin, Simona Belviso, Barbara Dal Bello, Luís Augusto Nero, Luca Cocolin
Technological properties and biogenic amine production were analyzed in 56 bacteriocinogenic lactococci and enterococci strains isolated from raw goat's milk. Fifteen lactococci strains were able to reduce milk pH to 5.3 or lower after 6 h, while enterococci strains were initially slow in producing acids. Lactococcus lactis subsp. lactis GLc06 and three strains of Enterococcus faecalis (GEn20, GEn22, and GEn23) presented high proteolytic activity. L. lactis subsp. lactis GLc06 and E. faecalis GEn22 also showed a high percentage of autolysis after only 4 h, reaching 71...
January 2017: Journal of Food Protection
https://www.readbyqxmd.com/read/28219688/mesoporous-phenylalanine-ammonia-lyase-microspheres-with-improved-stability-through-calcium-carbonate-templating
#16
Jiandong Cui, Yamin Zhao, Zhilei Tan, Cheng Zhong, Peipei Han, Shiru Jia
Cross-linked enzyme aggregates (CLEAs) have recently emerged as a promising method for enzyme immobilization due to its simplicity and low cost. However, a lack of good size and morphological control over the as-prepared CLEAs has limited their practical applications in some cases. Here, monodisperse spherical CLEAs of phenylalanine ammonia lyase (PAL microspheres) were prepared based on CaCO3 microtemplates. The preparation procedure involves filling porous CaCO3 microtemplates with the protein by salt precipitation, glutaraldehyde crosslinking, and dissolution of the microtemplates...
May 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28217122/listeria-monocytogenes-10403s-arginine-repressor-argr-finely-tunes-arginine-metabolism-regulation-under-acidic-conditions
#17
Changyong Cheng, Zhimei Dong, Xiao Han, Jing Sun, Hang Wang, Li Jiang, Yongchun Yang, Tiantian Ma, Zhongwei Chen, Jing Yu, Weihuan Fang, Houhui Song
Listeria monocytogenes is able to colonize human and animal intestinal tracts and to subsequently cross the intestinal barrier, causing systemic infection. For successful establishment of infection, L. monocytogenes must survive the low pH environment of the stomach. L. monocytogenes encodes a functional ArgR, a transcriptional regulator belonging to the ArgR/AhrC arginine repressor family. We aimed at clarifying the specific functions of ArgR in arginine metabolism regulation, and more importantly, in acid tolerance of L...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28213032/applicability-of-a-colorimetric-method-for-evaluation-of-lactic-acid-bacteria-with-probiotic-properties
#18
Min Young Jung, Jina Lee, Boyeon Park, Hyelyeon Hwang, Sung-Oh Sohn, Se Hee Lee, Hyeong In Lim, Hae Woong Park, Jong-Hee Lee
Rapid colorimetric methods using various indicator reagents have been developed to monitor bacterial viability. Here, we examined the applicability of a method based on the reduction of resazurin or water-soluble tetrazolium salt-8 (WST-8) to screen lactic acid bacteria (LAB) for growth, tolerance against bile acid and low pH. The resazurin reduction test proved unsuitable for screening LAB such as Lactobacillus plantarum and Leuconostoc mesenteroides since it reacted with acid present in the cultures. LAB growth could be indirectly quantified by measuring WST-8 reduction...
June 2017: Food Microbiology
https://www.readbyqxmd.com/read/28204982/influence-of-carbon-sources-on-the-viability-and-resuscitation-of-acetobacter-senegalensis-during-high-temperature-gluconic-acid-fermentation
#19
Rasoul Shafiei, Raziyeh Zarmehrkhorshid, Majid Mounir, Philippe Thonart, Frank Delvigne
Much research has been conducted about different types of fermentation at high temperature, but only a few of them have studied cell viability changes during high-temperature fermentation. In this study, Acetobacter senegalensis, a thermo-tolerant strain, was used for gluconic acid production at 38 °C. The influences of different carbon sources and physicochemical conditions on cell viability and the resuscitation of viable but nonculturable (VBNC) cells formed during fermentation were studied. Based on the obtained results, A...
February 15, 2017: Bioprocess and Biosystems Engineering
https://www.readbyqxmd.com/read/28197768/expression-of-an-acid-urease-with-urethanase-activity-in-e-coli-and-analysis-of-urease-gene
#20
REVIEW
Xiaofeng Liu, Qian Zhang, Nandi Zhou, Yaping Tian
Urea in alcoholic beverage is a precursor of ethyl carbamate (EC), which is carcinogenic. Enzymatic elimination of urea has attracted much research interest. Acid urease with good tolerance toward ethanol and acid is ideal enzyme for such applications. In the present work, the structural genes of urease from Providencia rettgeri JN-B815, ureABC were efficiently expressed in E. coli BL21(DE3) in an active form (apourease) exhibiting both urease and urethanase (hydrolyze EC) activities. The specific activities of the purified apourease were comparatively low, which were 2...
March 2017: Molecular Biotechnology
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