title: Construction and characterization of a cigR deletion mutant of Salmonella enterica serovar Pullorum.
abstract: Salmonella enterica serovar Pullorum (S. Pullorum) is the causative agent of pullorum disease (PD) and results in severe economic losses to the poultry industry. As a Salmonella type III secretion system 2 (T3SS2) effector and predicted membrane protein, CigR is encoded by the cigR gene within Salmonella pathogenicity island 3 (SPI3). In order to research the influence of the cigR gene on S. Pullorum, a cigR mutant of S. Pullorum S06004 was constructed by the lambda Red recombination system, and then its characterization was analysed. Lack of cigR did not affect the growth and biochemical properties, but resulted in decreased biofilm formation. The mutant strain was stable with the deletion of the cigR gene. Macrophage infection assay and in vivo competition assay showed that the mutant strain increased the replication and/or survival ability in the HD11 cell line and in chickens compared to that of the parent strain, the median lethal dose (LD50) of the mutant strain was one-fifth of the parent strain for 2-day-old chickens when injected intramuscularly. These results demonstrate CigR plays roles in biofilm formation and pathogenicity of S. Pullorum, deletion of cigR can significantly decrease biofilm formation and significantly increase virulence.
authors.affiliation: a Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses , Yangzhou University , Yangzhou , People's Republic of China.
authors.forename: Junlei
authors.initials: J
authors.lastname: Yin
authors.affiliation: a Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses , Yangzhou University , Yangzhou , People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Xia
authors.affiliation: a Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses , Yangzhou University , Yangzhou , People's Republic of China.
authors.forename: Mingxin
authors.initials: M
authors.lastname: Tao
authors.affiliation: a Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses , Yangzhou University , Yangzhou , People's Republic of China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Xu
authors.affiliation: a Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses , Yangzhou University , Yangzhou , People's Republic of China.
authors.forename: Qiuchun
authors.initials: Q
authors.lastname: Li
authors.affiliation: a Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses , Yangzhou University , Yangzhou , People's Republic of China.
authors.forename: Shizhong
authors.initials: S
authors.lastname: Geng
authors.affiliation: a Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses , Yangzhou University , Yangzhou , People's Republic of China.
authors.forename: Xinan
authors.initials: X
authors.lastname: Jiao
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D018441:Biofilms / Q000254:growth & development*; D002460:Cell Line; D002645:Chickens / Q000382:microbiology*; D017353:Gene Deletion; D044404:Genomic Islands / Q000235:genetics*; D008264:Macrophages / Q000382:microbiology; D011201:Poultry Diseases / Q000382:microbiology*; D012481:Salmonella Infections, Animal / Q000382:microbiology*; D019779:Salmonella enterica / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification / Q000472:pathogenicity*; D065288:Serogroup; D014774:Virulence
chemical_list: D001426:Bacterial Proteins
keywords: Salmonella enterica serovar Pullorum; biofilm formation; cigR gene; pathogenicity; type III secretion system