title: Hfq plays important roles in virulence and stress adaptation in Cronobacter sakazakii ATCC 29544.
abstract: Cronobacter spp. are opportunistic pathogens that cause neonatal meningitis and sepsis with high mortality in neonates. Despite the peril associated with Cronobacter infection, the mechanisms of pathogenesis are still being unraveled. Hfq, which is known as an RNA chaperone, participates in the interaction with bacterial small RNAs (sRNAs) to regulate posttranscriptionally the expression of various genes. Recent studies have demonstrated that Hfq contributes to the pathogenesis of numerous species of bacteria, and its roles are varied between bacterial species. Here, we tried to elucidate the role of Hfq in C. sakazakii virulence. In the absence of hfq, C. sakazakii was highly attenuated in dissemination in vivo, showed defects in invasion (3-fold) into animal cells and survival (10(3)-fold) within host cells, and exhibited low resistance to hydrogen peroxide (10(2)-fold). Remarkably, the loss of hfq led to hypermotility on soft agar, which is contrary to what has been observed in other pathogenic bacteria. The hyperflagellated bacteria were likely to be attributable to the increased transcription of genes associated with flagellar biosynthesis in a strain lacking hfq. Together, these data strongly suggest that hfq plays important roles in the virulence of C. sakazakii by participating in the regulation of multiple genes.
authors.affiliation: Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Research Institute for Agriculture and Life Sciences, and Center for Food and Bioconvergence, Seoul National University, Seoul, South Korea.
authors.forename: Seongok
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Research Institute for Agriculture and Life Sciences, and Center for Food and Bioconvergence, Seoul National University, Seoul, South Korea.
authors.forename: Hyelyeon
authors.initials: H
authors.lastname: Hwang
authors.affiliation: Department of Food Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju, South Korea.
authors.forename: Kwang-Pyo
authors.initials: KP
authors.lastname: Kim
authors.affiliation: Department of Molecular Science and Technology, Department of Applied Chemistry and Biological Engineering, Ajou University, Suwon, South Korea.
authors.forename: Hyunjin
authors.initials: H
authors.lastname: Yoon
authors.affiliation: Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Research Institute for Agriculture and Life Sciences, and Center for Food and Bioconvergence, Seoul National University, Seoul, South Korea.
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Kang
authors.affiliation: Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Research Institute for Agriculture and Life Sciences, and Center for Food and Bioconvergence, Seoul National University, Seoul, South Korea sangryu@snu.ac.kr.
authors.forename: Sangryeol
authors.initials: S
authors.lastname: Ryu
mesh_terms: D000818:Animals; D002460:Cell Line; D044083:Cronobacter sakazakii / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D004756:Enterobacteriaceae Infections / Q000382:microbiology* / Q000473:pathology; D055786:Gene Knockout Techniques; D035001:Host Factor 1 Protein / Q000235:genetics / Q000378:metabolism*; D008124:Locomotion; D008264:Macrophages / Q000382:microbiology; D008807:Mice, Inbred BALB C; D050296:Microbial Viability; D017207:Rats, Sprague-Dawley; D013312:Stress, Physiological; D014774:Virulence
chemical_list: D035001:Host Factor 1 Protein