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As an application instructional course for Aquatic Animal Medicine (AAM), Aquatic Animal Pathogen Biology needs to be guided by a large number of examples and cases, but the current case database construction faces many urgent problems. In view of this, this paper analyzes the characteristics of professional education of AAM postgraduate students. With the goal of cultivating applied personnel that meet the requirements of the times, and the guiding ideology of strengthening the reform of the education model in colleges and universities, and improving the quantity and quality of personnel training, it builds a case database for the course Aquatic Animal Pathogen Biology in accordance with modern postgraduate teaching needs. [ABSTRACT FROM AUTHOR]

[Objectives] The purpose was to investigate the function and mechanism of exsA gene in type III secretion system of Vibrio alginolyticus. [Methods] The full length of exsA was cloned using molecular biology techniques to analyze its biological information. Fluorescence quantitative PCR technology was used to analyze the expression of exsA after different media stress. [Results] The exsA gene contains an open reading frame (ORF) of 861 bp, encoding 286 amino acids. The physico-chemical analysis shows that the molecular structural formula is C1442H2267N393O441S12, the theoretical molecular weight is 32.549 kD, the theoretical pl value is 6. 0, and the protein is non-hydrophilic and unstable. The gene does not contain a transmembrane region, and there is no obvious signal peptide. The prediction result of protein subcellular localization shows that the protein is inside the cell. The deduced amino acid sequence and constructed phylogenetic tree show that V. alginolyticus has a close relationship with Vibrio antiquarius. The qPCR results show that the expression level of exsA in different media is different, highest in TSB medium containing bile salts, followed by DMEM medium, and lowest in ordinary TSB medium. [Conclusions] The gene sequence, molecular structure and isoelectric point of exsA, as well as its expression in three different media were obtained. [ABSTRACT FROM AUTHOR]

Objectives: To clone the pepck gene of Vibrio alginolyticus strain HY9901 and analyze its sequence by bioinformatics. Methods: According to the complete gene sequence of V alginolyticus on GenBank, specific primer were designed to amplify the target gene ppppC by PCR. The sequence of the pepck gene was analyzed using bioinformatics. The phylogenic tree of pepck gene and the corresponding single -subunit three-dimensional structure were constructed. & Results: The pepck gene of V alginolyticus strain HY9901 has a full length of 1 629 bp, with theoretical molecular weight of 60.12 kD. The prediction results show that there is no signal peptide or transmembrane region at the N-terminus of the sequence, the amino acid sequence contains 11 phosphorylation sites of casein kinase II. The prediction results of protein subcellular localization indicate that PEPEK protein is localized in the cytoplasm. The protein is stable and hydrophobic. The tertiary structure of the PEPCK protein of V alginolyticus is similar to that of Vibbo perahaemolgtcus. It is predicted that PEPCK has a major functional domain PEPCK_ATP. In the secondary structure, alpha helix, random coil, and extended strand accounted for 21. 96%, 52. 03% and 26.01%, respectively. The PEPCK homology between V. alginolyticus ad Vibrio diabbllcus is as high as 99%. Conclusions: This study lays the foundation for further under tanding the function of pepek gene in V alginolyticus. [ABSTRACT FROM AUTHOR]

[Objectives] This study aimed to clone the tye A gene of Vibrio alginolyticus HY9901 strain and analyze its sequence by bioinformatics. [Methods] By referring to the entire genome sequence of V. alginolyticus on Gen Bank, specific primers were designed. According to the principle of PCR amplification, the target gene tye A was amplified. By means of bioinformatics, the sequence of tye A was further analyzed, and the phylogenetic tree of tye A genes of Vibrio spp. and the corresponding subunit three-dimensional structure models were constructed. [Results] The length of the tye A gene of V. alginolyticus strain HY9901 is 285 bp, and its theoretical molecular weight is 10.98 kD. According to prediction, there is no signal peptide or transmembrane region at the N-terminus of the sequence, and the amino acid sequence contains two casein kinase II phosphorylation sites. The results of protein subcellular localization prediction show that the Tye A protein is located in the cell membrane. The protein is unstable and non-hydrophilic. The tertiary structure of Tye A protein of V. alginolyticus is similar to that of Yersinia sp. According to prediction, Tye A has a major functional domain Pfam. In terms of secondary structure, alpha helix, random coil, extended strand and beta turn account for 85.11%, 7.45%, 4.26% and 3.19%, respectively. The homology of Tye A between V. alginolyticus and Vibrio parahaemolyticus is up to 83%, so they are classified into one cluster. [Conclusions] This study will help to further understand the regulation mechanism of type III secretion system in V. alginolyticus. [ABSTRACT FROM AUTHOR]

In order to improve the professional competitiveness of students in the Aquatic Animal Medicine Discipline, combined with the case tracking and theoretical practice for aquatic animal medicine students for three years, with the aid of SPSS software, this paper elaborated the actual level and existing problems in career planning of aquatic animal medicine students in Guangdong Ocean University from five dimensions:career planning awareness, self-awareness, environmental awareness, goal planning, and implementation correction. Then, it discussed the opportunities and challenges of the Aquatic Animal Medicine Discipline in the context of the Belt and Road Initiative. Finally, it came up with solutions and reform recommendations in education, teaching, and counseling paths from the students, university, families, government, and society. [ABSTRACT FROM AUTHOR]

In this study' Hy322 gene was cloned from Vibrio alginolyticus. The total length of its gene was 969 bp' and it could encode 322 amino acids. The physicochemical properties, protein structure, genetic evolutionary relationship and antigenic characteristics of the effector protein Hy322 of V/ alginolyticus HY9901 type III secretion systemwere studied and analyzed by bioinformatics methods and tools. The results showed that Hy322 is an unstable hydrophilic and acidic protein without a transmembrane region and a signal pepide' and secondary sUucture to oí-helix. The evolutionary analysis showed that V alginolyticus HY9901 and V. harveyi were clustered together' which indicated that the genetic relationship between tie two species was closest. HY322 contains a FliN ssper family conserved domain associated with Flagellar motor switch. Bioinformatics analysis sZowed that the B-cell preponderant epitooes of Hy322 might be localized in the regions of 32-33' 100 -102' 138 - 140' 215 -216' 235 - 238 and 246 - 249. The 3D structure model of Hy322 ssbunit was simulated by SWISS-MODEL software and itwas found that the yscQof Yersinia were similar and the similarity was 42. 25 %. In this study' the feasibility of Hy322 as a common antigen of Virio was veūfied from the perspective of bioinformatics' which laid the foundation for the next step in vaccine development. [ABSTRACT FROM AUTHOR]

In this study' Va1686 gene was cloned from Vibrio alginolyticus. The total length of the gene is 1 164 bp' and it could encode 387 amino acids. The physicochemical properties, protein structure, genetic evolutionary relationship and antigenic characteristics of the effect protein Va1686 of V. algnolgtcus HY9901 type III secretion system were studied and analyzed by bioinformatics methods and tools. The results showed that Va1686 is a stable hydrophilic and acidic protein without a transmembrane region and a signal peptide, and secondary structure to α-helix. The evolutionary analysis showed that V. alginolyticus HY9901 and V. harveyi were clustered together which indicated that the genetic relationship between the two species was the closest. Va1686 contains a Fic superfamily conserved domain asociated with cell division. Bioinformatics analysis showed that the B-cell preponderant epitopes of Va1686 might be localized in the regions of 48 - 49, 82 - 85, 125 - 126, 150 - 153, 185 - 186, 236 - 237 and so on. The 3D structure model of Va1686 subunit was simulated by SWISS-MODEL software and it was found that the vopS of V. parahemolyticus was similar and the similarity was 89.46V. In this study' the feasibility of Va1686 as a common antigen of Vibrio was verified from the perspective of bioinformatics, which laid the foundation for the next step in vaccine development. [ABSTRACT FROM AUTHOR]

In order to explore the inhibitory effects of Prunus mume, Crataegus pinnatifida and Coptis chinensis on Vibrio parahaemolyticus and its biofilm ii vitro, the agar difusion method was applied. These three Chinese herbal medicines had diferent inhibitory effects on V parahaemolyticus. The inhibition zone of C. pinnatifida to V parahaemolyticus was (15.25 ± 53) mm, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of C. pinnatifida on V parahaemolyticus were both 31.25 mg/mL; the inhibition zone of C. chinensis to V parahaemolyticus was (18.08 ± 0.10) mm, and the MIC and MBC of C. chinensis on V parahaemolyticus were both 15.63 mg/mL; the inhibition zone of P. mume to V. parahaejnplyticus was (28.99 ± 0.47) mm, and the MIC and MBC of P. mume on V. parahaemolyticus were both 7.81 mg/mL. The effects of three traditional Chinese medicines on the biofilm formation of V. parahaemolyticus were tested by MTT colorimetric method using methylthiazolyl tetrazolium (MTT). P. mume, C. pinnatifida and C. chinensis have significant inhibitory effects on V. parahaemolyticus biofilm and their MIC are 7.8.1 mg/mL, 3.125 mg mL, and 62.5 mg mL, respectively (P <0.01). The experimental results are expected to provide certain references for the development of new fishery drugs. [ABSTRACT FROM AUTHOR]

[Objectives] This study aimed to analyze the biological activity and immunogenicity of extracellular products from Streptococcus iniae. [Methods] S. iniae was incubated with brain heart infusion agar medium (BHIA + 4% calf serum) for 60 h. The bacterial liquid was rinsed with PBS, centrifuged, and filtered through microporous filtering film to collect extracellular products (ECPs). [Results]Extracellular proteinase (ECPase) of S. iniae exhibited amylase, protease, lecitinase, gelatinase, lipase activities and hemolytic activity but had no urease activity. EDTA, DTT and PMSF could reduce ECPase activity to 72.4%, 77.6% and 72.4%, respectively. Cu2+, Ca2+, K+ and Mg2+ exhibited an inhibitory effect on ECPase activity, whereas Fe+, Co2+ and Mn2+ could activate ECPase activity. ECPs had good heat stability and exhibited relatively high activities under alkaline conditions. The optimal temperature for ECPs was 55t. Two-dimensional electrophoresis was performed to analyze the main protein of ECPs. The results indicated that there are 12 main bands of ECPs, and the molecular weights mainly ranged between 28 - 68 kDa. About 120 protein spots were detected, and the molecular weights mainly ranged between 26 - 95 kDa. The mouse anti-S. iniae was used for Western-blot analysis of ECPs, and the results showed that there were four proteins, with molecular weights of 26, 37, 95, and 97 kDa, respectively. The pathogenicity assay indicated that ECPs of S. iniae were highly pathogenic to tilapia. The mortality rate of tilapia was enhanced as the concentration of ECPs increased. [Conclusions] This study provided a certain theoretical basis for revealing the pathogenic mechanism of Streptococcus iniae. [ABSTRACT FROM AUTHOR]

[Objectives] To explore the inhibitory effects of Prunus mume, Coptis chinensis, and Crataegus pinnatifida on Vibrio alginolyticus and its biofilm in vitro. & Methods] The agar diffusion method was applied to determine the inhibition zone diameter of three Chinese herbal medicines on V alginolyticus; double dilution method was used to determine the minimum inhibitory concentration ( MIC) and minimum bactericidal concentration (MBC) of three Chinese herbal medicines on V alginolyticus; methylthiazolyl tetrazolium (MTT) method was applied to evalidate the effects of three Chinese herbal medicines on the biofilm formation of V alginolyticus. [ Results] The three Chinese herbal medicines had different, inhibitory effects on V alginolyticus. The inhibition zones of P. mume, C. chinensis, and C. pinnatifida on V alginolyticus were (18.31±0.29) mmt (20.31±0.30) mm' and (30.24±0.14) mmrespectively, and P. mume had strong bacteriostatic effects on V alginolyticus. The double dilution method was used to determine the bacteriostatic effects of three Chinese herbal medicines on V algi-nolyticus. Results showed that P. mume has the highest antibacterial and bactericidal ability. The MIC and MBC of P. mume, C. pinnatifida' and C. chinensis on V alginolyticus was 3.91'31.25' and 125 mgmL' respectively. Finally, MTT method was applied to evaluate the effects of C. pinnatifida' C. chinensis, and P. mume on the biofilm formation of V. alginolyticus, and results showed that the MIC on the biofilm for-mation of V. alginolyticus was 15. 63'7. 81' and 3. 91 mg mL' respectively; the MIC of P. mume was the lowest. [ Conclusions] This experiment proves that P. mume, C. chinensis, and C. pinnatifida have inhibitory effects on V. alginolyticus and its biofilm formation. It is expected to provide references for prevention and control of pathogenic vibrio induced diseases of aquatic animals. [ABSTRACT FROM AUTHOR]

In order to enrich the research about type III secretion system (T3SS) injectisome of Vibrio alginolyticus, vscX gene was cloned from V. alginolyticus strain HY9901 for bioinformatics analysis and expression analysis. Specific primers were designed according to the full-length genome sequence of V. alginolyticus in GenBank. vscX gene (GenBank accession number : FR780679) contained a 378 bp open reading frame (ORF), encoding a putative protein of 125 amino acids. The theoretical molecular weight was 14.209 2 kD and theoretical pi was 5.75. By using Signal 4.1 Server and TMHMM Server 2.0, it was predicted that VscX protein had no transmembrane domain or signal peptide. The results of prediction using SoftBerry-Psite software showed that VscX protein contained three casein kinase II phosphorylation sites, one N-myristoylation site and three C-terminal targeting signal sites. Subcellular localization revealed that VscX might be located in cytoplasm with the possibility of 56.5%. According to SMART prediction, VscX had one Pfam (1 - 125 aa) domain. Phylogenetic analysis revealed that VscX from V. alginolyticus and VscX from V. parahemolyticus were clustered into the same group. Network interaction analysis showed that vscX was adjacent to vscY, vopB and sycN. By real-time fluorescent quantitative PCR technique and 2-ΔΔt method, the differences in expression levels of VscX mRNA in V. alginolyticus strain HY9901, T3SS deletion strain ΔvscO and complementary strain C-vscO at different growth stages were analyzed. The results showed that the expression levels of VscX mRNA in V. alginolyticus strain HY9901 and C-vscO were significantly up-regulated at stable growth stage (P < 0.01); the expression levels of VscX mRNA in deletion strain ΔvscO were significantly up-regulated at late growth stage (P < 0. 01). This study provided the basis for revealing the transport mechanism of T3SS injectisome of V. alginolyticus. [ABSTRACT FROM AUTHOR]

As an important platform for the combination of theory and practice, college students' innovative and entrepreneurial training program has an important impact on improving the comprehensive ability of undergraduates. The major of aquatic animal medicine is a new sea-related major. The continuous development and transformation and upgrading of aquaculture in the new period have put forward newer and higher requirements for the innovative and practical ability and comprehensive quality of aquatic animal medicine graduates. Taking the innovation and entrepreneurship program of college students majoring in aquatic animal medicine as an example, this paper analyzes the significance of the innovation training program for college students, the cultivation of students' scientific research ability, and the problems existing in the application and operation of the program, in order to provide a reference for the innovative education and talent training for students majoring in aquatic animal medicine. [ABSTRACT FROM AUTHOR]

[ Obbective] This study aimed to analyze the in vitro inhibitory activity of Shisandra chinensis and Polygonatum sibiricum against Vibrio harveyi and its biofilms. [Result] By a a r diffusion test, in vitro inhibitory activity of S. chinensis a d P. sibiricum against V harveyi was investigated. The minima inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of S. chinensis and P. sibiricum against V. harveyi were determined by doubling dilution method. The inhibitory activity of S. chinensis a d P. sibiricum on the formation of V. harveyi biofilms was evaluated by modified MTT asay. [Result] Both S. chinensis and P. siiiricum had inhibitory activity aganst V harveyi. The inhibition zone diameter of S. chinensis aganst V harveyi was 17.95 mm; MIC and MBC of S. chinensis were both 3. 125 mg/ml. The inhibition zone diameter of P. sibiricum against V harveyi was 12. 22 mm; MIC and MBC of P. sibiricum were 3. 125 and 6.250 mg/ml, respectively. When the concentration was higher than 6.25 mg/ml, S. chinensis decoction had extremely significat inhibitory activity against V. harveyi (P <0. 01) ; when the concentration was higher t h a 3. 125 mg/ml, P. sirium had extremely significant inhibitory activity against V. harveyi (P <0. 01). [Conclusion] S. chinensis a d P. sibiricum could significantly inhibit V. harveyi and its biofilms. [ABSTRACT FROM AUTHOR]

In this study, histidine kinase gene kdpD in the two-component regulatory system of Vibrio alginolyticus strain HY9901 was cloned for bioinformatics analysis. Sequence analysis revealed that kdpD gene (GenBank accession number; KJ544668) was 1374 bp in length, encoding a putative protein of 457 amino acids. The predicted molecular weight (MW) of KdpE was 51.60 k.D with a theoretical isoelectric point (pi) of 6.02. Using SignalP4.0, TMHMM Server 2.0 and SoftBerry-Psite software, it was predicted that KdpE protein was equally located in Golgi apparatus, plasma membrane and endoplasmic reticulum (33.3%), which did not contain a signal peptide but contained three transmembrane domains. KdpE protein had five casein kinase II phosphorylation sites, five protein kinase C phosphorylation sites and one cAMP- and cGMP-dependent protein kinase phosphorylation site. A phylogenetic tree was constructed by MEGA 5.0 software, which revealed that KdpD from V. alginolyticus had close genetic relationship with corresponding proteins from V. campbellii and V. parahaemolyticus. Using SWISSMODEL Workspace, the three-dimensional structure of HATPase_c conserved domain in KdpD protein was constructed. These results may provide the basis for further studies on two-component regulatory system KdpD/KdpE of V. alginolyticus. [ABSTRACT FROM AUTHOR]

[Objective] This study aimed to investigate the role of dihydrolipoamide dehydrogenase (DLDH) in the pathopoiesis of Vibrio alginolyticus. [Method] Using suicide plasmid pRE112 as the vector, dldh deletion mutant strain ZJ03 Δdldh was constructed with insertion inactivation mutation method by Overlap PCR and homologous recombination technology to compare and analyze the differences in the growth, swimming ability, enzyme activity, biofilm formation and pathogenicity between wild-type strain ZJ03 and deletion mutant strain ZJ03 Δdldh. [Result] dldh deletion mutant strain ZJ03 Δdldh exhibited prolonged lag phase, significantly reduced swimming ability (P < 0. 05), significantly reduced enzyme activity (P < 0. 05), significantly reduced biofilm formation ability (P < 0.05) and remarkably reduced pathogenicity to Epinephelus coioides (P<0.05) compared to wild-type strain ZJ03. [Conclusion] This study provided theoretical basis for revealing the pathogenic mechanisms of Vibrio from the perspective of bacterial energy metabolism. [ABSTRACT FROM AUTHOR]

[Objectives] To clone the sucC gene of Vibrio alginolyticus strain HY9901 and conduct the bioinformatics analysis. [Methods] Based on the sucC gene of V. alginolyticus strain HY9901, specific primers were designed to amplify the full length sequence by PCR and make further analysis. [Results] The theoretical molecular weight of SucC protein was about41 528.45 Da, and the full length was 1 167 bp, encoding 388 amino acids. It has no signal peptide and transmembrane region, and has a variety of functional sites. It is predicted that it is mainly located in the cytoplasm, and the ubiquitin and lactate modification sites overlap, and it has high gene homology with Vibrio para haem olyti eus. The a-helix, random coil and extended strand are the main secondary structures. The similarity between the constructed three-level structure model and the template is high. [Conclusions] This study reveals the structural characteristics and functional potential of SucC protein, and provides a theoretical basis for the study of drug resistance mechanism and prevention strategies. [ABSTRACT FROM AUTHOR]

According to the clpX gene sequence of Vibrio alginolyticus HY9901, a pair of specific primers were designed, and the full length was cloned by PCR and subjected to bioinformatics analysis. The results showed that the clpX gene was 1 281 bp in length and encoded 426 amino acids. Its molecular structure formula was C3S42H64Q5N]2SjOj;i9SS26O, with a theoretical protein molecular weight of approximately 1 044 473.4 kDa and a theoretical pl value of 5.04. The clpX gene was predominantly situated within the cytoplasm, exhibiting unstable and hydrophilic protein characteristics. It possessed a signal peptide cleavage site, lacked a transmembrane region, and was not associated with any KEGG metabolic pathway. Additionally, it possessed 2 glycine phosphorylation sites, a CAMP-dependent protein kinase phosphorylation site, a C-terminal amidation modification site, 6 protein kinase C phosphorylation sites, 7 microbody C-terminal target signal sites, and an ATP/GTP site. The clpX phylogenetic tree was constructed using the MEGA 5. 0 software via the neighbor-joining method. The results demonstrated that the clpX of V. alginolyticus exhibited up to 100% affinity with the clpX of Vibrio spp. The single subunit 3D structure model of the ClpX protein was obtained using the SWISS-MODEL program. A structural and functional analysis of the protein revealed the presence of three distinct ClpX structural and functional domains. In the prediction of secondary structure, the proportions of a-helix, random coil, ß-sheet and extended strand were 40. 38%, 37.09%, 5.40% and 17.14%, respectively. The analysis of the ClpX protein through the STRING database revealed that the proteins interacting with the ClpX protein were Tig, Atpd, Hflb, Msrb-2, Rpod, Clpp, Clpa, Lon-1, Hfq, and ANP63951.1. A computational analysis of the ClpX protein identified a number of post-translational modification sites, including phosphorylation, acetylation, ubiquitination, glycosylation, methylation, S-palmitoylation, and lactylation. The significance of this study is to analyze the function of the clpX gene and establish a robust foundation for subsequent investigations into the mechanism of the clpX gene in Vibrio alginolyticus. [ABSTRACT FROM AUTHOR]

Vibrio alginolyticus is a zoonotic bacterium. A pair of specific primers was designed using the sodB gene sequence of Vibrio alginolyticus HY9901 in order to amplify the full length of the gene by PCR. The results indicated that the total length of the sodB gene was 585 bp and that it could encode 194 amino acids. The predicted amino acid sequence derivation indicated that the molecular weight of the protein was approximately 21.56 kDa, with an isoelectric point of 4.95. Upon prediction of the N-terminal signal peptide structure of the protein, no significant signal peptide cleavage site was observed, indicating that the protein lacked both a signal peptide and a transmembrane region. The amino acid sequence contained an N-glycosylation site, a casein kinase II phosphorylation site, a microsomal C-terminal target signal site, and a manganese and iron superoxide dismutase signal site. The probability of intracytoplasmic localization of the SodB protein was 56.5%, which was analyzed according to the subcellular localization of the protein. The amino acid sequence of the sodB gene of V. alginolyticus exhibited 98% -100% homology to other Vibrio species, clustering into the same subfamily with V. parahaem, indicating a relatively close relationship between them. In the prediction of protein structure, the proportions of a-helix, random coil, ß-sheet, and extended strand were 48.45%, 30. 41%, 5.67%, and 15. 46%, respectively. The similarity to template ldtO. 1. A reached 71.58%. A PTM site analysis revealed the presence of phosphorylation, glycosylation, ubiquitination, sumoylation, acetylation, and methylation modification sites, as well as the absence of lactylation modification sites. [ABSTRACT FROM AUTHOR]

Vibrio harveyi is an important pathogen that causes vibriosis in various aquatic organisms. Here, we announce the draft genome sequence of V. harveyi strain ZJ0603, which was isolated from diseased Orange-spotted grouper (Epinephelus coioides) in Guangdong, China. [ABSTRACT FROM AUTHOR]