通讯机构：
[Yu, X.] C;College of Veterinary Medicine, China
关键词：
ADE;Cba;gene knockout;immunization;Streptococcus suis
摘要：
Streptococcus suis (SS) is a zoonotic pathogen that affects the health of humans and the development of the pig industry. The SS Cba protein is a collagen adhesin, and a few of its homologs are related to the enhancement of bacterial adhesion. We compared the phenotypes of SS9-P10, SS9-P10 cba knockout strains and its complementary strains in vitro and in vivo and found that knocking out the cba gene did not affect the growth characteristics of the strain, but it significantly reduced the ability of SS to form biofilms, adhesion to host cells, phagocytic resistance to macrophages and attenuated virulence in a mouse infection model. These results indicated that Cba was a virulence related factor of SS9. In addition, Mice immunized with the Cba protein had higher mortality and more serious organ lesions after challenge, and the same was observed in passive immunization experiments. This phenomenon is similar to the antibody-dependent enhancement of infection by bacteria such as Acinetobacter baumannii and Streptococcus pneumoniae. To our knowledge, this is the first demonstration of antibody-dependent enhancement of SS, and these observations highlight the complexity of antibody-based therapy for SS infection.
摘要：
血管生成素 4(ANG4)是一种新型抗菌肽蛋白, 具有抗菌、抗炎、血管生成、调节机体免疫反应等多种生物学功能, 在机体先天免疫过程中发挥重要的作用。 ANG4在新生小鼠肠道的表达受到多种因素的调节, 如细菌信号和发育过程等。本试验选取细菌细胞壁表面分子的类似物壳寡糖( COS)作为诱导物, 探究其对小鼠肠道 ANG4表达和对肠道形态的影响。实时荧光定量聚合酶链式反应( qRT-PCR)和蛋白质免疫印迹( Western blot)分析表明, COS能增加小鼠肠道 ANG4 mRNA及 ANG4蛋白的表达；形态学观察结果显示, COS使小肠绒毛高度明显增加, 平均隐窝深度均有降低, V/C值增加, 表明 COS可通过诱导 ANG4等抗菌蛋白的表达, 或通过其杀菌和免疫调节作用而不同程度地提高小肠黏膜的完整性。研究结果为 COS以及 ANG4在仔猪肠道疾病防治的应用提供了理 Angiogenin 4 (ANG4), a novel antimicrobial protein with multiple biological functions, such as antimicrobial, anti-inflammation, angiogenesis and regulating the body’s immune response, plays a key role in innate immunity. The expres-sion of ANG4 in neonatal mice intestine is regulated by some factors including microbial signal and developmental stage. Being an analogue of surface molecules of bacterial cell wall, chitosan oligosaccharide (COS) was selected as a inducer to explore the effects on ANG4 expression and mophology in post weaning mice intestine. qRT-PCR and Western blot analyses showed that the mRNA and protein levels of ANG4 increased suggesting that COS can upregulate the expression of ANG4. The results of HE staining of mouse intestinal tract showed that the height of intestinal villi, the depth of crypt and the value of V/C increased significantly. It indicates that COS can improve the integrity of intestinal mucosae in some extent through either inducing the expression of some intestinal antimicrobial proteins, such as ANG4, or its antimicrobial and immunomodulation activities, and provide the theoretical basis for the applications of COS and ANG4 in controlling the intestinal diseases in piglets. Key words: ANG4; COS; AMPs; qRT-PCR; Western blot
摘要：
Ampelopsis grossedentata (AG) is mainly distributed in Chinese provinces and areas south of the Yangtze River Basin. It is mostly concentrated or scattered in mountainous bushes or woods with high humidity. Approximately 57 chemical components of AG have been identified, including flavonoids, phenols, steroids and terpenoids, volatile components, and other chemical components. In vitro studies have shown that the flavone of AG has therapeutic properties such as anti-bacteria, anti-inflammation, anti-oxidation, enhancing immunity, regulating glucose and lipid metabolism, being hepatoprotective, and being anti-tumor with no toxicity. Through searching and combing the related literature, this paper comprehensively and systematically summarizes the research progress of AG, including morphology, traditional and modern uses, chemical composition and structure, and pharmacological and toxicological effects, with a view to providing references for AG-related research.
摘要：
Tick saliva is a reservoir of bioactive proteins. Saliva protein compositions change dynamically during blood-feeding. Decipherment of protein profiles in different blood-feeding stages may bring deeper insight into tick feeding physiology and provide targets for immunologic control alternatives. However, having the infancy of tick genome sequencing, assembly, annotation, and limited knowledge of tick salivary proteins restrain the data interpretation. Here, we aimed to depict the saliva protein profile in partially- (PE) and fully-engorged (FE) Haemaphysalis flava ticks, with a special focus on the analysis of those uncharacterized proteins. Saliva was collected from PE and FE adult female H. flava ticks. Saliva proteins were analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC/MS-MS). MS data were searched against an in-house salivary gland transcriptome library for identification of tick-derived proteins. Abundances of proteins were compared between PE and FE ticks. The uncharacterized proteins detected in saliva were further bioinformatically analyzed. In total, 614 proteins were identified including 94 host proteins and 520 tick-derived proteins. The 226 tick-derived high-confidence proteins were classified into 10 categories: transporters, enzymes, protease inhibitors, immunity-related proteins, lipocalins, glycine-rich proteins, muscle proteins, secreted proteins, uncharacterized proteins and others. A total of 98 proteins were shared in both PE and FE with 74 only in PE and 54 only in FE. Abundances of 24 shared proteins were significantly higher in PE. The profile of top 15 most abundant proteins was also different between PE and FE ticks. The 65 uncharacterized proteins detected in tick saliva were branched into subclusters 1A, 1B, 2, 3A, 3B and 3C based on particular motifs like RGD, LRR, indicating their diverse predicted functions like anti-coagulation, regulation of innate immune, or other functions. This study provides and compares saliva proteomes of H. flava ticks in two feeding stages with special cluster analysis on the uncharacterized proteins. Further investigations are needed to confirm the roles of these uncharacterized proteins in ticks.
作者机构：
[Luo, Dan; Jiang, Sujuan; Liu, Yisong; Xiao, Gang; Zeng, Jianguo; Yang, Yang; Ding, Tingyu] Hunan Agr Univ, Coll Vet Med, Changsha 410125, Peoples R China.;[Ding, Tingyu] Loudi Vocat & Tech Coll, Loudi 417000, Peoples R China.;[Yue, Meishan; Huang, Jialu; Zeng, Jianguo; Su, Yue] Shanxi Agr Univ, Coll Vet Med, Taiyuan 030031, Peoples R China.
通讯机构：
[Jianguo Zeng; Yisong Liu] A;Authors to whom correspondence should be addressed.<&wdkj&>College of Veterinary Medicine, Hunan Agricultural University, Changsha 410125, China<&wdkj&>College of Veterinary Medicine, Shanxi Agricultural University, Taiyuan 030031, China<&wdkj&>Authors to whom correspondence should be addressed.<&wdkj&>College of Veterinary Medicine, Hunan Agricultural University, Changsha 410125, China
通讯机构：
[Liu, GH ] H;Hunan Agr Univ, Coll Vet Med, Res Ctr Parasites & Vectors, Changsha 410128, Hunan, Peoples R China.
关键词：
Hard ticks;Mitochondrial genome;Mitochondrial DNA;Phylogenetic analyses
摘要：
Ticks are blood-sucking ectoparasites with significant medical and veterinary importance, capable of transmitting bacteria, protozoa, fungi, and viruses that cause a variety of human and animal diseases worldwide. In the present study, we sequenced the complete mitochondrial (mt) genomes of five hard tick species and analyzed features of their gene contents and genome organizations. The complete mt genomes of Haemaphysalis verticalis, H. flava, H. longicornis, Rhipicephalus sanguineus and Hyalomma asiaticum were 14855 bp, 14689 bp, 14693 bp, 14715 bp and 14722 bp in size, respectively. Their gene contents and arrangements are the same as those of most species of metastriate Ixodida, but distinct from species of genus Ixodes. Phylogenetic analyses using concatenated amino acid sequences of 13 protein-coding genes with two different computational algorithms (Bayesian inference and maximum likelihood) revealed the monophylies of the genera Rhipicephalus, Ixodes and Amblyomma, however, rejected the monophyly of the genus Haemaphysalis. To our knowledge, this is the first report of the complete mt genome of H. verticalis. These datasets provide useful mtDNA markers for further studies of the identification and classification of hard ticks.
摘要：
Currently, the identification of herb metabolites is challenging due to a lack of clear standards. Here, using Gelsemium as an example, we present a protocol for characterizing target components of herbs. This approach utilizes high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry guided by an in-house herb metabolite database based on reported studies and mass spectrometry. We describe steps for creating an in-house database, preparing and detecting samples, processing data, and characterizing compounds. This approach offers a reference for future research on the identification of herb metabolites. For complete details on the use and execution of this protocol, please refer to Liu etal. (2017).(1).
通讯机构：
[Zhan, Y.] P;[Wang, C.] A;Provincial Key Laboratory of Protein Engineering in Animal Vaccines, Hunan, China;Animal Disease Prevention and Control Center of Hunan Province, Hunan, China
关键词：
Porcine circovirus type 2 (PCV2);porcine circovirus type 3 (PCV3);Porcine parvovirus (PPV);Pseudorabies virus (PRV);Multiplex real-time PCR
期刊：
Journal of Microbiology,2023年61(4):433-448 ISSN：1225-8873
通讯作者：
Tang, Yulong;Fang, Lihua
作者机构：
[Jia, Xinglin; Pan, Yanying; Zhao, Chijun; Ji, Chunxiao] Hunan Agr Univ, Coll Vet Med, Changsha 410125, Peoples R China.;[Fang, Lihua; Liu, Quan] Foshan Univ, Sch Life Sci & Engn, Foshan 528225, Guangdong, Peoples R China.;[Kuang, Guangwei; Zhang, Shuo; Liao, Simeng; Tang, Yulong; Wu, Xin] Chinese Acad Sci, Inst Subtrop Agr, Changsha 410125, Peoples R China.;[Tang, Yulong] Anhui Prov Key Lab Livestock & Poultry Prod Safety, Hefei 230001, Peoples R China.;[Zhang, Shuo] South Southwest Agr & Anim Husb Grp Ltd, Kunming 650217, Peoples R China.
通讯机构：
[Tang, Yulong] I;[Fang, Lihua] S;Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China.;Anhui Province Key Laboratory of Livestock and Poultry Product Safety Engineering, Hefei, 230001, China.;School of Life Science and Engineering, Foshan University, Foshan, 528225, Guangdong, China.
关键词：
Streptococcus suis serotype 2;Thioredoxin system;Anti-phagocytosis;Oxidative stress
摘要：
Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen that can infect humans in contact with infected pigs or their byproducts. It can employ different types of genes to defend against oxidative stress and ensure its survival. The thioredoxin (Trx) system is a key antioxidant system that contributes adversity adaptation and pathogenicity. SS2 has been shown to encode putative thioredoxin genes, but the biological roles, coding sequence, and underlying mechanisms remains uncharacterized. Here, we demonstrated that SSU05_0237-ORF, from a clinical SS2 strain, ZJ081101, encodes a protein of 104 amino acids with a canonical CGPC active motif and an identity 70-85% similar to the thioredoxin A (TrxA) in other microorganisms. Recombinant TrxA efficiently catalyzed the thiol-disulfide oxidoreduction of insulin. The deletion of TrxA led to a significantly slow growth and markedly compromised tolerance of the pathogen to temperature stress, as well as impaired adhesion ability to pig intestinal epithelial cells (IPEC-J2). However, it was not involved in H(2)O(2) and paraquat-induced oxidative stress. Compared with the wild-type strain, the ΔTrxA strain was more susceptible to killing by macrophages through increasing NO production. Treatment with TrxA mutant strain also significantly attenuated cytotoxic effects on RAW 264.7 cells by inhibiting inflammatory response and apoptosis. Knockdown of pentraxin 3 in RAW 264.7 cells was more vulnerable to phagocytic activity, and TrxA promoted SS2 survival in phagocytic cells depending on pentraxin 3 activity compared with the wild-type strain. Moreover, a co-inoculation experiment in mice revealed that TrxA mutant strain is far more easily cleared from the body than the wild type strain in the period from 8-24h, and exhibits significantly attenuated oxidative stress and liver injury. In summary, we reveal the important role of TrxA in the pathogenesis of SS2.
通讯机构：
[Wan, FC ; Liu, L ] H;Hunan Agr Univ, Coll Anim Sci & Technol, Changsha, Hunan, Peoples R China.;Hunan Agr Univ, Coll Vet Med, Changsha, Hunan, Peoples R China.
关键词：
L-leucine;beef cattle;in vitro technique;rumen protection rate;rumen fermentation;bacterial community
摘要：
This study was conducted to compare the effects of rumen-protected (RP-Leu) and unprotected L-leucine (RU-Leu) on the fermentation parameters, bacterial composition, and amino acid metabolism in vitro rumen batch incubation. The 5.00 g RP-Leu or RU-Leu products were incubated in situ in the rumen of four beef cattle (Bos taurus) and removed after 0, 2, 4, 6, 12, 16, and 24 h to determine the rumen protection rate. In in vitro incubation, both RP-Leu and RU-Leu were supplemented 1.5 mmol/bottle (L-leucine HCl), and incubated after 0, 2, 4, 6, 8, 12, and 16 h to measure gas production (GP), nutrient degradability, fermentation parameters, bacterial composition, and amino acids metabolism. Results from both in vitro and in situ experiments confirmed that the rumen protection rate was greater (p < 0.01) in RP-Leu than in RU-Leu, whereas the latter was slow (p < 0.05) degraded within incubation 8 h. Free leucine from RP-Leu and RU-Leu reached a peak at incubation 6 h (p < 0.01). RU-Leu supplementation increased (p < 0.05) gas production, microbial crude protein, branched-chain AAs, propionate and branched-chain VFAs concentrations, and Shannon and Sobs index in comparison to the control and RP-Leu supplementation. RU-Leu and RP-Leu supplementation decreased (p < 0.05) the relative abundance of Bacteroidota, which Firmicutes increased (p < 0.05). Correlation analysis indicated that there are 5 bacteria at the genus level that may be positively correlated with MCP and propionate (p < 0.05). Based on the result, we found that RP-Leu was more stable than RU-Leu in rumen fluid, but RU-Leu also does not exhibit rapid degradation by ruminal microbes for a short time. The RU-Leu was more beneficial in terms of regulating rumen fermentation pattern, microbial crude protein synthesis, and branched-chain VFAs production than RP-Leu in vitro rumen conditions.
