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Cheng-Zhe Ren Hui-Min Gao Jun Dai Wen-Zhuo Zhu Fei-Fei Xu Yun Ye Xiao-Ling Zhang Qiao Yang 《Marine drugs》2022,20(5)
Microalgae host varied microbial consortium harboring cross-kingdom interactions with fundamental ecological significance in aquatic ecosystems. Revealing the complex biofunctions of the cultivable bacteria of phycosphere microbiota is one vital basis for deeply understanding the mechanisms governing these dynamic associations. In this study, a new light-yellow pigmented bacterial strain LZ-28 was isolated from the highly-toxic and harmful algal bloom-forming dinoflagellate Alexandrium catenella LZT09. Collective phenotypic and genotypic profiles were obtained to confidently identify this strain as a new Mameliella alba member. Comparative genomic analysis showed that strain LZ-28 shared highly similar functional features with other four marine algae-derived M. alba strains in spite of their distinctive isolation sources. Based on the bioactivity assaying, the mutual growth-promoting effects between bacterial strain LZ-28 and algal strain LZT09 were observed. After the culture conditions were optimized, strain LZ-28 demonstrated an extraordinary production ability for its bioflocculanting exopolysaccharides (EPS). Moreover, the portions of two monosaccharides glucose and fucose of the EPS were found to positively contribute to the bioflocculanting capacity. Therefore, the present study sheds light on the similar genomic features among the selected M. alba strains, and it also reveals the potential pharmaceutical, environmental and biotechnological implications of active EPS produced by this new Mameliella alba strain LZ-28 recovered from toxic bloom-forming marine dinoflagellate. 相似文献
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Lingyu Xu Chenfu Cao Zhiyi Yang Weixin Jia 《Journal of veterinary science (Suw?n-si, Korea)》2022,23(4)
BackgroundASF was first reported in Kenya in 1910 in 1921. In China, ASF spread to 31 provinces including Henan and Jiangsu within six months after it was first reported on August 3, 2018. The epidemic almost affected the whole China, causing direct economic losses of tens of billions of yuan. Cause great loss to our pig industry. As ELISA is cheap and easy to operate, OIE regards it as the preferred serological method for ASF detection. P54 protein has good antigenicity and is an ideal antigen for detection.ObjectiveTo identify a conservative site in the African swine fever virus (ASFV) p54 protein and perform a Cloth-enzyme-linked immunosorbent assay (ELISA) for detecting the ASFV antibody in order to reduce risks posed by using the live virus in diagnostic assays.MethodWe used bioinformatics methods to predict the antigen epitope of the ASFV p54 protein in combination with the antigenic index and artificially synthesized the predicted antigen epitope peptides. Using ASFV-positive serum and specific monoclonal antibodies (mAbs), we performed indirect ELISA and blocking ELISA to verify the immunological properties of the predicted epitope polypeptide.ResultsThe results of our prediction revealed that the possible antigen epitope regions were A23–29, A36–45, A72–94, A114–120, A124–130, and A137–150. The indirect ELISA showed that the peptides A23–29, A36–45, A72–94, A114–120, and A137–150 have good antigenicity. Moreover, the A36–45 polypeptide can react specifically with the mAb secreted by hybridoma cells, and its binding site contains a minimum number of essential amino acids in the sequence 37DIQFINPY44.ConclusionsOur study confirmed a conservative antigenic site in the ASFV p54 protein and its amino acid sequence. A competitive ELISA method for detecting ASFV antibodies was established based on recombinant p54 and matching mAb. Moreover, testing the protein sequence alignment verified that the method can theoretically detect antibodies produced by pigs affected by nearly all ASFVs worldwide. 相似文献
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中国上古社会伦理政治的演进 总被引:1,自引:0,他引:1
中国上古社会政治文化随着夏商周神权政治统治的式微和伦理政治实践的推行,到春秋战国时期人文礼治的兴起,尤其是原始儒家确立起以伦理主导政治与以政治实践伦理的伦理政治模式,呈现出由多元走向一元的总体趋势。 相似文献
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滴头流道中颗粒物质运移动态分析与CFD模拟 总被引:5,自引:0,他引:5
采用CFD模拟技术,对迷宫式滴头流道内不同质量浓度的悬浮颗粒运动情况进行数字化模拟计算,并采用两相流动力学理论对迷宫式滴头结构尺度下的悬浮颗粒的随流性进行了分析,研究结果表明,采用DPM模型对悬浮颗粒分布特点的模拟结果与已有试验数据吻合度较高,可以作为模拟的手段;水流中颗粒质量浓度对滴头内部流场有着较强的反作用,应在模拟过程中予以重视;根据Stokes数的计算结果,10%左右的颗粒随流性差,可以认为导致滴头堵塞的物质主要来自于这一部分颗粒。 相似文献
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