Pyropia yezoensis(formerly Porphyra yezoensis)is an economically important red alga that is cultured extensively in China.The red rot disease occurs commonly during Pyropia cultivation,causing serious economic losses....Pyropia yezoensis(formerly Porphyra yezoensis)is an economically important red alga that is cultured extensively in China.The red rot disease occurs commonly during Pyropia cultivation,causing serious economic losses.An incidence of red rot disease was found in a P.yezoensis farm from mid-November to mid-December 2015 at Lianyungang,Jiangsu Province,China.Histopathological examination revealed that the naturally infected thalli were infected apparently by a pathogen,leading to red rot symptoms.The causative agent was isolated and identified as the oomycete Pythium chondricola by morphological analysis and sequence analysis of the internal transcribed spacer and cytochrome oxidase subunit 1(cox 1).In artifi cial infection experiments on the P.yezoensis blades,the P.chondricola isolate was able to cause the same characteristic histopathology seen in natural infections.P.chondricola grew well at a wide range of temperatures in the range 8-31℃,salinities at 0-45 and pH 5-9.In an orthogonal test used to determine the effects of environmental factors(temperature,salinity,and zoospore concentration)on infection,the data revealed that temperature was the most important factor to affect red rot disease development,with the optimal conditions for disease expansion being 20℃,35 salinity,and a zoospore concentration of 10^6 zoospores/mL.The results obtained from the present study prompted us to set up a comprehensive epidemiological study on Pyropia,which will provide support to maintain the healthy development of the Pyropia industry in China.展开更多
Pseudoalteromonas marina is one of the potential pathogens that cause green spot disease(GSD)in Pyropia yezoensis.To prevent GSD from development and spread,an effective method to detect the pathogen at early GSD infe...Pseudoalteromonas marina is one of the potential pathogens that cause green spot disease(GSD)in Pyropia yezoensis.To prevent GSD from development and spread,an effective method to detect the pathogen at early GSD infection stages need to be established.In this research,PCR methods were established targeting the dnaA gene(encoding chromosome replication initiator protein)and the dnaN gene(encodingβsliding clamp of DNA polymeraseⅢprotein)to detect P.marina with three primer pairs pws-dnaA2(Forward,5'-ACCGCATTAACGAACTACTCGTG-3';Reverse,5'-TGCCATTACCTACAGCATGG-3'),pcs-dnaN2(Forward,5'-CTTACAACGTTATCAGCGGC-3';Reverse,5'-GTTGAGTATTAAGTGATTGAGTAAGC-3')or pws-dnaN3(Forward,5'-ACTTACAA-CGTTATCAGCGGC-3';Reverse,5'-ACTGCTGTTTGAGTCTGCTAAC-3').Three PCR methods corresponding to the three primer pairs sufficiently distinguished P.marina from 22 bacterial species,thus resulting in detection limits of 4 to 4×10^2 CFU cells or 2.37×10^1 to 2.37×10^3 fg of P.marina DNA per PCR reaction.In an artificial infection experiment ofP.yezoensis infected with P.marina,all established PCRs successfully detected P.marina at early GSD infection stages.The results show that the established PCRs are specific and sensitive,and are potential for applications in early diagnosis of GSD in Pyropia.展开更多
As a marine bacterial pathogen, Photobacterium damselae subsp. damselae(PDD) is distributed in seawater worldwide. It can infect different animals as well as humans, even cause deaths. The highly conserved regions of ...As a marine bacterial pathogen, Photobacterium damselae subsp. damselae(PDD) is distributed in seawater worldwide. It can infect different animals as well as humans, even cause deaths. The highly conserved regions of PDD mcp gene on chromosome and dly gene on plasmid were selected as the target fragments to design the specific primers. Recombinant plasmid standard was prepared based on the primers. With GENECHECKER UF-150 qRT-PCR instrument as the platform, a fluorescence-based quantitative real-time PCR(qRT-PCR) method was established for the detection of PDD. This method can specifically detect PDD and distinguish the highly virulent strains. Additionally, the test results can be qualitatively judged by visualization, while the quantitative detection can be achieved through the standard curve calculation. The minimum limit of detection was 1.0×101 copies μL-1, and the detection time was less than 20 min. In summary, this new method has outstanding advantages, such as strong specificity, high sensitivity, and low site requirements. It is a rapid on-site detection technology for highly virulent PDD strains.展开更多
Brine shrimp(Artemia)has existed on Earth for 400 million years and has major ecological importance in hypersaline ecosystems.As a crucial live food in aquaculture,brine shrimp cysts have become one of the most import...Brine shrimp(Artemia)has existed on Earth for 400 million years and has major ecological importance in hypersaline ecosystems.As a crucial live food in aquaculture,brine shrimp cysts have become one of the most important aquatic products traded worldwide.However,our understanding of the biodiversity,prevalence and global connectedness of viruses in brine shrimp is still very limited.A total of 143 batches of brine shrimp(belonging to seven species)cysts were collected from six continents including 21 countries and more than 100 geographic locations worldwide during 1977–2019.In total,55 novel RNA viruses were identified,which could be assigned to 18 different viral families and related clades.Eleven viruses were dsRNA viruses,16 were+ssRNA viruses,and 28 were−ssRNA viruses.Phylogenetic analyses of the RNA-directed RNA polymerase(RdRp)showed that brine shrimp viruses were often grouped with viruses isolated from other invertebrates and fungi.Remarkably,most brine shrimp viruses were related to those from different hosts that might feed on brine shrimp or share the same ecological niche.A notable case was the novel brine shrimp noda-like virus 3,which shared 79.25%(RdRp)and 63.88%(capsid proteins)amino acid identity with covert mortality nodavirus(CMNV)that may cause losses in aquaculture.In addition,both virome composition and phylogenetic analyses revealed global connectedness in certain brine shrimp viruses,particularly among Asia and Northern America.This highlights the incredible species diversity of viruses in these ancient species and provides essential data for the prevalence of RNA viruses in the global aquaculture industry.More broadly,these findings provide novel insights into the previously unrecognized RNA virosphere in hypersaline ecosystems worldwide and demonstrate that human activity might have driven the global connectedness of brine shrimp viruses.展开更多
基金Supported by the China Agriculture Research System(No.CARS-50)the National Natural Sciences Foundation of China(No.31372517)+2 种基金the Fundamental Research Funds for the Central Universities(No.201562018)the National Infrastructure of Fishery Germplasm Resources(No.2017DKA30470)the Project of Aoshan Scientific and Technological Innovation Program of Qingdao National Laboratory for Marine Science and Technology(No.2015ASKJ02)
文摘Pyropia yezoensis(formerly Porphyra yezoensis)is an economically important red alga that is cultured extensively in China.The red rot disease occurs commonly during Pyropia cultivation,causing serious economic losses.An incidence of red rot disease was found in a P.yezoensis farm from mid-November to mid-December 2015 at Lianyungang,Jiangsu Province,China.Histopathological examination revealed that the naturally infected thalli were infected apparently by a pathogen,leading to red rot symptoms.The causative agent was isolated and identified as the oomycete Pythium chondricola by morphological analysis and sequence analysis of the internal transcribed spacer and cytochrome oxidase subunit 1(cox 1).In artifi cial infection experiments on the P.yezoensis blades,the P.chondricola isolate was able to cause the same characteristic histopathology seen in natural infections.P.chondricola grew well at a wide range of temperatures in the range 8-31℃,salinities at 0-45 and pH 5-9.In an orthogonal test used to determine the effects of environmental factors(temperature,salinity,and zoospore concentration)on infection,the data revealed that temperature was the most important factor to affect red rot disease development,with the optimal conditions for disease expansion being 20℃,35 salinity,and a zoospore concentration of 10^6 zoospores/mL.The results obtained from the present study prompted us to set up a comprehensive epidemiological study on Pyropia,which will provide support to maintain the healthy development of the Pyropia industry in China.
基金Supported by the China Agriculture Research System(No.CARS-50)the National High-Tech R&D Program of China(No.2012AA10A406)+1 种基金the National Science and Technology Infrastructure Platform Construction(No.2018DKA30470)the Aoshan Technology Innovation Program of Qingdao National Laboratory for Marine Science and Technology(No.2015ASKJ02)
文摘Pseudoalteromonas marina is one of the potential pathogens that cause green spot disease(GSD)in Pyropia yezoensis.To prevent GSD from development and spread,an effective method to detect the pathogen at early GSD infection stages need to be established.In this research,PCR methods were established targeting the dnaA gene(encoding chromosome replication initiator protein)and the dnaN gene(encodingβsliding clamp of DNA polymeraseⅢprotein)to detect P.marina with three primer pairs pws-dnaA2(Forward,5'-ACCGCATTAACGAACTACTCGTG-3';Reverse,5'-TGCCATTACCTACAGCATGG-3'),pcs-dnaN2(Forward,5'-CTTACAACGTTATCAGCGGC-3';Reverse,5'-GTTGAGTATTAAGTGATTGAGTAAGC-3')or pws-dnaN3(Forward,5'-ACTTACAA-CGTTATCAGCGGC-3';Reverse,5'-ACTGCTGTTTGAGTCTGCTAAC-3').Three PCR methods corresponding to the three primer pairs sufficiently distinguished P.marina from 22 bacterial species,thus resulting in detection limits of 4 to 4×10^2 CFU cells or 2.37×10^1 to 2.37×10^3 fg of P.marina DNA per PCR reaction.In an artificial infection experiment ofP.yezoensis infected with P.marina,all established PCRs successfully detected P.marina at early GSD infection stages.The results show that the established PCRs are specific and sensitive,and are potential for applications in early diagnosis of GSD in Pyropia.
基金supported by the National Key Research and Development Program of China (No. 2019YFD0900104)the Key Projects of Science and Technology In-novation of Shandong Province (No. 2018YFJH0703)。
文摘As a marine bacterial pathogen, Photobacterium damselae subsp. damselae(PDD) is distributed in seawater worldwide. It can infect different animals as well as humans, even cause deaths. The highly conserved regions of PDD mcp gene on chromosome and dly gene on plasmid were selected as the target fragments to design the specific primers. Recombinant plasmid standard was prepared based on the primers. With GENECHECKER UF-150 qRT-PCR instrument as the platform, a fluorescence-based quantitative real-time PCR(qRT-PCR) method was established for the detection of PDD. This method can specifically detect PDD and distinguish the highly virulent strains. Additionally, the test results can be qualitatively judged by visualization, while the quantitative detection can be achieved through the standard curve calculation. The minimum limit of detection was 1.0×101 copies μL-1, and the detection time was less than 20 min. In summary, this new method has outstanding advantages, such as strong specificity, high sensitivity, and low site requirements. It is a rapid on-site detection technology for highly virulent PDD strains.
基金This work was supported by the National Key Research and Development Program of China(2018YFD0900501)Central Public-interest Scientific Institution Basal Research Fund,YSFRI,CAFS(20603022022005)+6 种基金Shinan District Science and Technology Foundation(Qingdao)(2022-2-027-ZH)Central Public-interest Scientific Institution Basal Research Fund,CAFS(2020TD39)China Agriculture Research System(CARS-48)C.L.was supported by the Youth Innovation Team of Shandong Higher Education Institution(2021KJ064)the National Natural Science Foundation of China(32200004)W.S.was supported by the Academic Promotion Programme of Shandong First Medical University(2019QL006)E.C.H.was funded by a National Medical Health and Research Council(Australia)Investigator Grant(GNT2017197).
文摘Brine shrimp(Artemia)has existed on Earth for 400 million years and has major ecological importance in hypersaline ecosystems.As a crucial live food in aquaculture,brine shrimp cysts have become one of the most important aquatic products traded worldwide.However,our understanding of the biodiversity,prevalence and global connectedness of viruses in brine shrimp is still very limited.A total of 143 batches of brine shrimp(belonging to seven species)cysts were collected from six continents including 21 countries and more than 100 geographic locations worldwide during 1977–2019.In total,55 novel RNA viruses were identified,which could be assigned to 18 different viral families and related clades.Eleven viruses were dsRNA viruses,16 were+ssRNA viruses,and 28 were−ssRNA viruses.Phylogenetic analyses of the RNA-directed RNA polymerase(RdRp)showed that brine shrimp viruses were often grouped with viruses isolated from other invertebrates and fungi.Remarkably,most brine shrimp viruses were related to those from different hosts that might feed on brine shrimp or share the same ecological niche.A notable case was the novel brine shrimp noda-like virus 3,which shared 79.25%(RdRp)and 63.88%(capsid proteins)amino acid identity with covert mortality nodavirus(CMNV)that may cause losses in aquaculture.In addition,both virome composition and phylogenetic analyses revealed global connectedness in certain brine shrimp viruses,particularly among Asia and Northern America.This highlights the incredible species diversity of viruses in these ancient species and provides essential data for the prevalence of RNA viruses in the global aquaculture industry.More broadly,these findings provide novel insights into the previously unrecognized RNA virosphere in hypersaline ecosystems worldwide and demonstrate that human activity might have driven the global connectedness of brine shrimp viruses.