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181.
Piyush Parkhey Aadil Keshaw Ram Batul Diwan J. Satya Eswari 《Preparative biochemistry & biotechnology》2020,50(8):768-780
AbstractThe present study demonstrates a comparative analysis between the artificial neural network (ANN) and response surface methodology (RSM) as optimization tools for pretreatment and enzymatic hydrolysis of lignocellulosic rice straw. The efficacy for both the processes, that is, pretreatment and enzymatic hydrolysis was evaluated using correlation coefficient (R2) & mean squared error (MSE). The values of R2 obtained by ANN after training, validation, and testing were 1, 0.9005, and 0.997 for pretreatment and 0.962, 0.923, and 0.9941 for enzymatic saccharification, respectively. On the other hand, the R2 values obtained with RSM were 0.9965 for cellulose recovery and 0.9994 for saccharification efficiency. Thus, ANN and RSM together successfully identify the substantial process conditions for rice straw pretreatment and enzymatic saccharification. The percentage of error for ANN and RSM were 0.009 and 0.01 for cellulose recovery and for 0.004 and 0.005 for saccharification efficiency, respectively, which showed the authority of ANN in exemplifying the non-linear behavior of the system. 相似文献
182.
《Mycoscience》2020,61(2):85-94
A mitogen-activated protein kinase (MAPK) signaling pathway regulates specialized cellular responses to external stimuli. In Bipolaris maydis, a Chk1 MAPK orthologous to Fus3/Kss1 MAPKs of Saccharomyces cerevisiae is known to regulate various developmental processes, including the formation of appressoria. However, upstream factors that regulate the Chk1 cascade have not been well clarified. In this study, we identified and characterized the BmSte50 gene, an ortholog of the yeast Ste50 in B. maydis. Our yeast two-hybrid assay indicated that BmSte50 interacts with a MAPK kinase kinase BmSte11, a component of the Chk1 cascade. ΔBmSte50 strains exhibited a loss of pathogenicity due to a lack of appressorial formation. The mutants also showed a reduction in melanization, conidial production, and aerial-mycelial and sexual development. Such phenotypes of the mutants were consistent with those of the Chk1 cascade gene mutants previously reported. In addition, ΔBmSte50 strains indicated lower conidial germination efficiency than the wild type. Notably, a significant number of ΔBmSte50 conidia could be germinated, while the Chk1 cascade gene mutants were reported to lack conidial germination ability. Our results suggested that BmSte50 may act as an adaptor protein for the Chk1 cascade and is involved in the regulation of various cellular processes. 相似文献
183.
《Saudi Journal of Biological Sciences》2020,27(10):2719-2726
This study investigated the interaction between polyphenols with different cereal sources and their effects on performance, serum biochemistry, corticosterone levels and carcass characteristics in broiler chickens reared under hot-humid environment. Newly hatched coloured broiler chicks (n = 240) were randomly divided into six groups with five replicates of two different cereal sources, namely corn and broken rice-sorghum combined, and three levels of pomegranate peel polyphenol extracts (PPP) 0, 50 and 100 mg/kg in each cereal groups. Birds were maintained under standard management conditions for six weeks during hot-humid environment (Temperature: 29–36 °C; Relative Humidity: 69–80%). Fortnight body weight and feed consumption were recorded and serum biochemical constituents were estimated at 28 and 42 days of age. The body weight gain was significantly (p < 0.05) higher in broken rice-sorghum diet than in corn diet. The supplementation of polyphenols increased the skin and shank pigmentation. Serum protein, lipids and minerals showed significant difference due to cereals, polyphenols and their interactions. Corn-fed birds had significantly higher visceral organs weight than the alternate grain-fed broilers. The serum corticosterone levels were significantly reduced in the PPP supplemented groups than the control, it could be concluded that, supplementation of 50 mg/kg polyphenol extract from pomegranate peels improved production performance in broilers fed broken rice-sorghum as cereal source under hot-humid conditions. 相似文献
184.
On‐site predetection of pathogens could significantly decrease of a disease outbreak or national loss in most of the countries. However, conventional detection techniques are limited in use for on‐site detection due to the necessity of specialized skill or equipment. Therefore, it is necessary to develop a new technique that can predetect pathogens in the field without special skills or equipment. Here, a DNAzyme strategy to control a plasmonic biosensor for rapid and simple visual detection of Salmonella choleraesuis is adopted. Multicomponent DNAzyme formed by target addition can cleave the linker effectively at 50 °C. Linker cleavage induces dispersion of two DNA‐immobilized gold nanoparticles and color change. Under optimized assay conditions, the target could be detected via visual discrimination sensitively and specifically. Moreover, the biosensor shows the possibility of practical use with contaminants and a 16S rRNA real target. As a result, the proposed plasmonic biosensor can visually detect S. choleraesuis without unstable enzymes, a specialized technique, or equipment. Therefore, these advantages could allow that this biosensor would be used for on‐site predetection to lower the risk of transmission of infectious diseases. 相似文献
185.
Miyuki Kusajima Moeka Fujita Hiromoto Yamakawa Tsukasa Ushiwatari Takamasa Mori Kazuki Tsukamoto 《Bioscience, biotechnology, and biochemistry》2020,84(7):1427-1435
ABSTRACT A newly identified chemical, 4-{3-[(3,5-dichloro-2-hydroxybenzylidene)amino]propyl}-4,5-dihydro-1H-pyrazol-5-one (BAPP) was characterized as a plant immunity activator. BAPP enhanced disease resistance in rice against rice blast disease and expression of a defense-related gene without growth inhibition. Moreover, BAPP was able to enhance disease resistance in dicotyledonous tomato and Arabidopsis plants against bacterial pathogen without growth inhibition, suggesting that BAPP could be a candidate as an effective plant activator. Analysis using Arabidopsis sid2-1 and npr1-2 mutants suggested that BAPP induced systemic acquired resistance (SAR) by stimulating between salicylic acid biosynthesis and NPR1, the SA receptor protein, in the SAR signaling pathway. 相似文献
186.
187.
Xiaojun Cheng Meiyao Pan Zhiguo E Yong Zhou Baixiao Niu Chen Chen 《The Plant journal : for cell and molecular biology》2020,104(1):124-137
Fertilization Independent Endosperm (FIE) is an essential member of Polycomb Repressive Complex 2 (PRC2) that plays important roles in the developmental regulation of plants. OsFIE1 and OsFIE2 are two FIE homologs in the rice genome. Here, we showed that OsFIE1 probably duplicated from OsFIE2 after the origin of the tribe Oryzeae, but has a specific expression pattern and methylation landscape. During evolution, OsFIE1 underwent a less intensive purifying selection than did OsFIE2. The mutant osfie1 produced smaller seeds and displayed reduced dormancy, indicating that OsFIE1 predominantly functions in late seed development. Ectopic expression of OsFIE1, but not OsFIE2, was deleterious to vegetative growth in a dose‐dependent manner. The newly evolved N‐terminal tail of OsFIE1 was probably not the cause of the adverse effects on vegetative growth. The CRISPR/Cas9‐derived mutant osfie2 exhibited impaired cellularization of the endosperm, which suggested that OsFIE2 is indispensable for early seed development as a positive regulator of cellularization. Autonomous endosperm was observed in both OsFIE2+? and osfie1/OsFIE2+? but at a very low frequency. Although OsFIE1‐PRC2 exhibited H3K27me3 methyltransferase ability in plants, OsFIE1‐PRC2 is likely to be less important for development in rice than is OsFIE2‐PRC2. Our findings revealed the functional divergence of OsFIE1 and OsFIE2 and shed light on their distinct evolution following duplication. 相似文献
188.
189.
Xiu‐li Liu Lan Wang Xiao‐wen Wang Yan Yan Xiao‐li Yang Meng‐yang Xie Zhi Hu Xing Shen Hao Ai Hong‐hui Lin Guo‐hua Xu Jian Yang Shu‐bin Sun 《The Plant journal : for cell and molecular biology》2020,102(1):53-67
Phosphorus (P) is an essential macronutrient required for plant development and production. The mechanisms regulating phosphate (Pi) uptake are well established, but the function of chloroplast Pi homeostasis is poorly understood in Oryza sativa (rice). PHT2;1 is one of the transporters/translocators mediating Pi import into chloroplasts. In this study, to gain insight into the role of OsPHT2;1‐mediated stroma Pi, we analyzed OsPHT2;1 function in Pi utilization and photoprotection. Our results showed that OsPHT2;1 was induced by Pi starvation and light exposure. Cell‐based assays showed that OsPHT2;1 localized to the chloroplast envelope and functioned as a low‐affinity Pi transporter. The ospht2;1 had reduced Pi accumulation, plant growth and photosynthetic rates. Metabolite profiling revealed that 52.6% of the decreased metabolites in ospht2;1 plants were flavonoids, which was further confirmed by 40% lower content of total flavonoids compared with the wild type. As a consequence, ospht2;1 plants were more sensitive to UV‐B irradiation. Moreover, the content of phenylalanine, the precursor of flavonoids, was also reduced, and was largely associated with the repressed expression of ADT1/MTR1. Furthermore, the ospht2;1 plants showed decreased grain yields at relatively high levels of UV‐B irradiance. In summary, OsPHT2;1 functions as a chloroplast‐localized low‐affinity Pi transporter that mediates UV tolerance and rice yields at different latitudes. 相似文献
190.