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91.
An inhibitor-tolerance strain, Bacillus coagulans GKN316, was developed through atmospheric and room temperature plasma (ARTP) mutation and evolution experiment in condensed dilute-acid hydrolysate (CDH) of corn stover. The fermentabilities of other hydrolysates with B. coagulans GKN316 and the parental strain B. coagulans NL01 were assessed. When using condensed acid-catalyzed steam-exploded hydrolysate (CASEH), condensed acid-catalyzed liquid hot water hydrolysate (CALH) and condensed acid-catalyzed sulfite hydrolysate (CASH) as substrates, the concentration of lactic acid reached 45.39, 16.83, and 18.71 g/L by B. coagulans GKN316, respectively. But for B. coagulans NL01, only CASEH could be directly fermented to produce 15.47 g/L lactic acid. The individual inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), vanillin, syringaldehyde and p-hydroxybenzaldehyde (pHBal) on xylose utilization by B. coagulans GKN316 was also studied. The strain B. coagulans GKN316 could effectively convert these toxic inhibitors to the less toxic corresponding alcohols in situ. These results suggested that B. coagulans GKN316 was well suited to production of lactic acid from undetoxified lignocellulosic hydrolysates. 相似文献
92.
【目的】研究和厚朴酚(HNK)抑制MRSA生物被膜(BF)形成的作用机制。【方法】使用TTC法测定了HNK对供试菌株BF的形成和成熟BF的抑制作用;刚果红平板法定性检测了HNK对PIA合成的影响;分光光度法测定了HNK对供试菌株eDNA释放量的影响;RT-PCR技术检测了HNK对供试菌株icaA、cidA以及agrA基因表达量的影响。【结果】HNK对MRSA 41573 BF的形成和成熟BF均有较强的抑制作用,其中,HNK抑制MRSA 41573 BF形成的MIC和MBC分别为10μg/mL和20μg/mL;抑制成熟BF的MIC和MBC分别为50μg/mL和100μg/mL。当用亚抑菌浓度的HNK与万古霉素联合作用后,可显著提高成熟BF对万古霉素的敏感性。HNK能显著抑制PIA的合成,且呈浓度剂量依赖。HNK能抑制供试菌株eDNA的释放量,其中1/8 MIC的HNK作用供试菌株16 h后,与对照组相比,e DNA的释放量降低了28.3%。HNK可抑制供试菌株BF形成的相关基因,其中1/2 MIC的HNK作用供试菌株16 h后,与对照相比,icaA的表达量降低了59.1%,cidA的表达量降低了56%,agrA的表达量降低了72.3%。【结论】HNK能显著抑制MRSA 41573 BF的形成,其作用机制主要是通过抑制icaA和cidA基因表达量,影响PIA和eDNA的合成,进而抑制BF的形成。此外HNK也可通过调控细菌的QS系统影响BF的形成。 相似文献
93.
Taotao Feng Xiaoyu ChenXiuwen Qiao Zhao SunHaining Wang Yu Qi Chenglin Hong 《Analytical biochemistry》2016
In this work, a simple electrochemical immunosensor was developed for the detection of carcinoembryonic antigen (CEA) based on rhombic dodecahedral Cu2O nanocrystals–graphene oxide–gold nanoparticles (rCu2O–GO–AuNPs). GO as the template and surfactant resulting in rCu2O exhibit improved rhombic dodecahedral structure uniformity and excellent electrochemical performance. Moreover, GO was found to be able to effectively improve the long stability of rCu2O on the electrode response. Under optimal conditions, the immunosensor showed a low limit of detection (0.004 ng ml−1) and a large linear range (0.01–120 ng ml−1). This work presents a potential alternative for the diagnostic applications of GO-supported special morphology materials in biomedicine and biosensors. 相似文献
94.
Chun-Long Li Mei Wang Xiao-Meng Wu Dong-Hua Chen Hong-Jun Lv Jian-Lin Shen Zhu Qiao Wei Zhang 《Plant physiology》2016,170(2):1090-1104
95.
Diachronic analysis of genetic diversity in rice landraces under on-farm conservation in Yunnan,China 总被引:1,自引:0,他引:1
96.
Length‐weight relationships of five fish species from the Yalong and Wujiang rivers (tributaries of Yangtze River,China) 下载免费PDF全文
L. Pan S. R. Yang L. Wan Z. Yang Z. Li Y. Qiao 《Zeitschrift fur angewandte Ichthyologie》2016,32(3):503-504
Length‐weight relationships (LWRs) were determined for five endemic fish species from the Yalong and Wujiang rivers (tributaries of the Yangtze River, China): Folifer brevifilis (Peters, 1881), Pelteobagrus ussuriensis (Dybowski, 1872), Schistura fasciolata (Nichols & Pope, 1927), Triplophysa daqiaoensis (Ding, 1993) and Triplophysa orientalis (Herzenstein, 1888). Samples were obtained between April 2004 and July 2014 using various fishing gear (set nets, drift gill nets, fish cages, hook and electro fishing). For each specimen from each species the sample size was recorded, total length and weight were measured and the LWR determined. Further, the 95% confidence intervals of a and b, and coefficient of correlation were estimated. Prior to this study, the LWRs for these five species were unknown. 相似文献
97.
High‐throughput multiplex cpDNA resequencing clarifies the genetic diversity and genetic relationships among Brassica napus,Brassica rapa and Brassica oleracea 下载免费PDF全文
Jiangwei Qiao Mengxian Cai Guixin Yan Nian Wang Feng Li Binyun Chen Guizhen Gao Kun Xu Jun Li Xiaoming Wu 《Plant biotechnology journal》2016,14(1):409-418
Brassica napus (rapeseed) is a recent allotetraploid plant and the second most important oilseed crop worldwide. The origin of B. napus and the genetic relationships with its diploid ancestor species remain largely unresolved. Here, chloroplast DNA (cpDNA) from 488 B. napus accessions of global origin, 139 B. rapa accessions and 49 B. oleracea accessions were populationally resequenced using Illumina Solexa sequencing technologies. The intraspecific cpDNA variants and their allelic frequencies were called genomewide and further validated via EcoTILLING analyses of the rpo region. The cpDNA of the current global B. napus population comprises more than 400 variants (SNPs and short InDels) and maintains one predominant haplotype (Bncp1). Whole‐genome resequencing of the cpDNA of Bncp1 haplotype eliminated its direct inheritance from any accession of the B. rapa or B. oleracea species. The distribution of the polymorphism information content (PIC) values for each variant demonstrated that B. napus has much lower cpDNA diversity than B. rapa; however, a vast majority of the wild and cultivated B. oleracea specimens appeared to share one same distinct cpDNA haplotype, in contrast to its wild C‐genome relatives. This finding suggests that the cpDNA of the three Brassica species is well differentiated. The predominant B. napus cpDNA haplotype may have originated from uninvestigated relatives or from interactions between cpDNA mutations and natural/artificial selection during speciation and evolution. These exhaustive data on variation in cpDNA would provide fundamental data for research on cpDNA and chloroplasts. 相似文献
98.
Integrated long non‐coding RNA analyses identify novel regulators of epithelial‐mesenchymal transition in the mouse model of pulmonary fibrosis 下载免费PDF全文
99.
100.
Lulu Hu Chen-hui Gao Chao Hong Qiao Zhong Xiao-Ming Gao 《Bioscience, biotechnology, and biochemistry》2016,80(2):257-263
Lactoferrin (LTF), a multifunctional glycoprotein of the transferrin family mainly found in exotic secretions in mammals, is an important defense molecule against not only microbial invasion but also tumors. It folds into two globular domains (N- and C-lobes) each containing an iron-binding site. The cationic antimicrobial peptide in N-lobe is known to exert anti-tumor effect via a non-receptor-mediated pathway. However, whether LTF C-lobe also contributes to its anti-tumor activity remains to be investigated. In this study, a human LTF fragment (amino acid residues 343–682) covering the C-lobe was expressed with a histidine tag in E. coli and the purified polypeptide refolded through a series of buffer changing procedure. The resultant recombinant protein caused significant growth arrest of breast carcinoma cells MDA-MB-231 in a dose- and time-dependent manner, evidently via induction of apoptosis of the cell. Our data suggest a positive role for the C-lobe of human LTF in controlling tumors in vitro. 相似文献