College of Life Science, Luoyang Normal University, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China.
Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China; College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China.
Vet Microbiol. 2021 Dec;263:109270. doi: 10.1016/j.vetmic.2021.109270. Epub 2021 Nov 2.
As a zoonotic pathogen, Streptococcus suis(S. suis) takes pigs as the main host and is mainly colonizes in the upper respiratory tract and tonsil of pigs, causing septicemia, endocarditis and meningitis in pigs. Pyruvate dehydrogenase (PDH) is an enzyme that catalyzes the conversion of pyruvate to acetyl-CoA. As an immunogenic membrane-associated protein in S. suis, it has been found to be closely related to the formation of biofilm. In this study, the recombinant PDH (rPDH) of S. suis ZY05719 (serotype 2) was expressed and purified in E. coli by His affinity chromatography. Western blotting analysis showed that there was a strong specific reaction between PDH protein and PDH antiserum. Mice were immunized with recombinant PDH and inactivated bacteria, and the relative survival rates were 70 % and 60 %, respectively. In addition, mice immunized with PDH caused high levels of antibodies and high expression of immune-related genes in the spleen, which significantly protected the liver, brain and spleen from pathological damage. In addition, PDH antiserum could significantly inhibit the growth of S. suis and the formation of S. suis biofilm in vitro. These results further suggest that PDH is a promising candidate for S. suis biofilm-related subunit vaccine.
作为一种人畜共患病病原体，猪链球菌（Streptococcus suis，S. suis）以猪为主要宿主，主要定植于猪的上呼吸道和扁桃体，引起猪的败血症、心内膜炎和脑膜炎。丙酮酸脱氢酶（Pyruvate dehydrogenase，PDH）是一种催化丙酮酸转化为乙酰辅酶 A 的酶。作为 S. suis 的一种免疫原性膜相关蛋白，它与生物膜的形成密切相关。在本研究中，通过 His 亲和层析在大肠杆菌中表达和纯化了 S. suis ZY05719（血清型 2）的重组 PDH（rPDH）。Western blot 分析表明，PDH 蛋白与 PDH 抗血清之间存在强烈的特异性反应。用重组 PDH 和灭活菌免疫小鼠，相对存活率分别为 70%和 60%。此外，用 PDH 免疫的小鼠引起高水平的抗体和免疫相关基因在脾脏中的高表达，显著保护肝脏、大脑和脾脏免受病理损伤。此外，PDH 抗血清可显著抑制 S. suis 的生长和体外 S. suis 生物膜的形成。这些结果进一步表明，PDH 是一种有前途的 S. suis 生物膜相关亚单位疫苗候选物。
