title: Contribution of methionine sulfoxide reductase B (MsrB) to Francisella tularensis infection in mice.
abstract: The essential mechanisms and virulence factors enabling Francisella species to replicate inside host macrophages are not fully understood. Methionine sulfoxide reductase (Msr) is an antioxidant enzyme that converts oxidized methionine into methionine. Francisella tularensis carries msrA and msrB in different parts of its chromosome. In this study, single and double mutants of msrA and msrB were constructed, and the characteristics of these mutants were investigated. The msrB mutant exhibited decreased in vitro growth, exogenous oxidative stress resistance and intracellular growth in macrophages, whereas the msrA mutant displayed little difference with wild-type strain. The double mutant exhibited the same characteristics as the msrB mutant. The bacterial count of the msrB mutant was significantly lower than that of the wild-type strain in the liver and spleen of mice. The bacterial count of the msrA mutant was lower than that of the wild-type strain in the liver, but not in the spleen, of mice. These results suggest that MsrB has an important role in the intracellular replication of F. tularensis in macrophages and infection in mice.
authors.affiliation: The United Graduate School of Veterinary Science, Yamaguchi University, 1677-1. Yoshida, Yamaguchi 753-8515, Japan.|Department of Pathology and Parasitology, Patuakhali Science and Technology, Babugonj, Barisal-8210, Bangladesh.
authors.forename: Shib Shankar
authors.initials: SS
authors.lastname: Saha
authors.affiliation: The United Graduate School of Veterinary Science, Yamaguchi University, 1677-1. Yoshida, Yamaguchi 753-8515, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Hashino
authors.affiliation: The United Graduate School of Veterinary Science, Yamaguchi University, 1677-1. Yoshida, Yamaguchi 753-8515, Japan.
authors.forename: Jin
authors.initials: J
authors.lastname: Suzuki
authors.affiliation: Department of Veterinary Science, National Institute of Infectious Diseases, Shinjuku, Tokyo 162-8640, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Uda
authors.affiliation: The United Graduate School of Veterinary Science, Yamaguchi University, 1677-1. Yoshida, Yamaguchi 753-8515, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: The United Graduate School of Veterinary Science, Yamaguchi University, 1677-1. Yoshida, Yamaguchi 753-8515, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Shimizu
authors.affiliation: The United Graduate School of Veterinary Science, Yamaguchi University, 1677-1. Yoshida, Yamaguchi 753-8515, Japan watarai@yamaguchi-u.ac.jp.
authors.forename: Masahisa
authors.initials: M
authors.lastname: Watarai
mesh_terms: D000818:Animals; D058491:Bacterial Load; D002460:Cell Line; D004361:Drug Tolerance; D005260:Female; D005604:Francisella tularensis / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development / Q000472:pathogenicity; D017353:Gene Deletion; D054884:Host-Pathogen Interactions; D008099:Liver / Q000382:microbiology; D008264:Macrophages / Q000382:microbiology; D051150:Methionine Sulfoxide Reductases / Q000235:genetics / Q000378:metabolism*; D008810:Mice, Inbred C57BL; D016877:Oxidants / Q000633:toxicity; D013154:Spleen / Q000382:microbiology; D014406:Tularemia / Q000382:microbiology* / Q000473:pathology*; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D016877:Oxidants; D037521:Virulence Factors; D051150:Methionine Sulfoxide Reductases
keywords: Francisella tularensis; intracellular replication; methionine sulfoxide reductase; oxidative stress