The ability of S. flexneri 2a virulent and avirulent (vaccine) strains No. 516 and No. 516 m to displace one another during long-term carrier state in germ-free rats has been studied. The long-term persistence of the vaccine strain in the intestine of the rats has been shown to produce colonization resistance to subsequent infection with the virulent culture of these bacteria. During carrier state in rats progressive S--R dissociation of the bacteria occurs, type II antigen is lost with simultaneous retention of group 3, 4 antigens and the resulting transformation of S. flexneri, serotype 2a, into variant y; the virulence of Shigella S-forms is also lost.
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Appl Microbiol Biotechnol
January 2025
State Key Laboratory of Oral Diseases, National Center for Stomatology, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China.
Aloe vera (L.) Burm.f.
View Article and Find Full Text PDFPLoS Pathog
January 2025
Chair of Phytopathology, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.
Wheat production is threatened by multiple fungal pathogens, such as the wheat powdery mildew fungus (Blumeria graminis f. sp. tritici, Bgt).
View Article and Find Full Text PDFMicroorganisms
December 2024
Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan, Chatuchak, Bangkok 10900, Thailand.
Vibriosis caused by is a major problem in aquatic animals, particularly brown marble groupers (). biotype I has recently been isolated and classified into subgroups SUKU_G1, SUKU_G2, and SUKU_G3 according to the different types of virulence genes. In a previous study, we have shown that biotype I strains were classified into three subgroups according to the different types of virulence genes, which exhibited different phenotypes in terms of growth rate and virulence.
View Article and Find Full Text PDFPathogens
December 2024
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou 310000, China.
pv. () is the causative agent of rice bacterial blight (RBB), resulting in substantial harvest losses and posing a challenge to maintaining a stable global supply. In this study, strains isolated from Shaoxing, Quzhou, and Taizhou, where RBB occurred most frequently in Zhejiang Province in 2019, were selected as the subjects of research.
View Article and Find Full Text PDFInsects
December 2024
College of Life Sciences, Xinyang Normal University, Xinyang 464000, China.
Brown planthoppers (BPHs, Stål) are a major threat to rice cultivation in Asia, necessitating the development of pest-resistant varieties for effective management. However, the adaptability of BPHs has resulted in the development of virulent populations, such as biotype Y BPHs, which exhibit significant virulence against the rice variety YHY15 that harbors the resistance gene . The various response mechanisms of BPH populations to resistant rice varieties are critical yet underexplored.
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