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以草鱼呼肠孤病毒(GCRV)873毒株为试验材料,建立了GCRV荧光定量PCR检测方法;用GCRV873株感染CIK细胞及草鱼,通过对病毒RNA复制水平、子代病毒含量以及细胞病变等情况进行监测,研究其在CIK细胞及草鱼体内的生长特性。在CIK细胞中,GCRV感染后12 h即可检测到子代病毒,36 h时,所有细胞被感染;72 h时,病毒滴度达到最高,为10~(6.75) TCID_(50)/mL。在草鱼的肝、脾、肾中,均能检测到GCRV RNA,其中肾脏中含量最高,其次是肝脏,脾脏中最少。本试验为研究GCRV致病机理及制备细胞灭活疫苗奠定了试验基础。 相似文献
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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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