title: Genomic and Phenotypic Analyses Reveal the Emergence of an Atypical Salmonella enterica Serovar Senftenberg Variant in China.
abstract: Human infections with Salmonella enterica subspecies enterica serovar Senftenberg are often associated with exposure to poultry flocks, farm environments, or contaminated food. The recent emergence of multidrug-resistant isolates has raised public health concerns. In this study, comparative genomics and phenotypic analysis were used to characterize 14 Salmonella Senftenberg clinical isolates recovered from multiple outbreaks in Shenzhen and Shanghai, China, between 2002 and 2011. Single-nucleotide polymorphism analyses identified two phylogenetically distinct clades of S Senftenberg, designated SC1 and SC2, harboring variations in Salmonella pathogenicity island 1 (SPI-1) and SPI-2 and exhibiting distinct biochemical and phenotypic signatures. Although the two variants shared the same serotype, the SC2 isolates of sequence type 14 (ST14) harbored intact SPI-1 and -2 and hence were characterized by possessing efficient invasion capabilities. In contrast, the SC1 isolates had structural deletion patterns in both SPI-1 and -2 that correlated with an impaired capacity to invade cultured human cells and also the year of their isolation. These atypical SC1 isolates also lacked the capacity to produce hydrogen sulfide. These findings highlight the emergence of atypical Salmonella Senftenberg variants in China and provide genetic validation that variants lacking SPI-1 and regions of SPI-2, which leads to impaired invasion capacity, can still cause clinical disease. These data have identified an emerging public health concern and highlight the need to strengthen surveillance to detect the prevalence and transmission of nontyphoidal Salmonella species.
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia Moataz.mohamed@kaust.edu.sa huqinghua03@163.com.
authors.forename: Moataz
authors.initials: M
authors.lastname: Abd El Ghany
authors.affiliation: Shenzhen Centre for Disease Control and Prevention, Shenzhen, Guangdong Province, China.
authors.forename: Xiaolu
authors.initials: X
authors.lastname: Shi
authors.affiliation: Shenzhen Centre for Disease Control and Prevention, Shenzhen, Guangdong Province, China.
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Li
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Hifzur R
authors.initials: HR
authors.lastname: Ansari
authors.affiliation: Marie Bashir Institute for Infectious Diseases and Biosecurity and School of Public Health, University of Sydney, Sydney, Australia.
authors.forename: Grant A
authors.initials: GA
authors.lastname: Hill-Cawthorne
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Y S
authors.initials: YS
authors.lastname: Ho
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Raeece
authors.initials: R
authors.lastname: Naeem
authors.affiliation: The Wellcome Trust Sanger Institute (WTSI), the Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom.
authors.forename: Derek
authors.initials: D
authors.lastname: Pickard
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: John D
authors.initials: JD
authors.lastname: Klena
authors.affiliation: Shanghai Municipal Center for Disease Control and Prevention, Shanghai, China.
authors.forename: Xuebing
authors.initials: X
authors.lastname: Xu
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Arnab
authors.initials: A
authors.lastname: Pain
authors.affiliation: Shenzhen Centre for Disease Control and Prevention, Shenzhen, Guangdong Province, China Moataz.mohamed@kaust.edu.sa huqinghua03@163.com.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Hu
mesh_terms: D000328:Adult; D000368:Aged; D015373:Bacterial Typing Techniques; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D004196:Disease Outbreaks; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D010802:Phylogeny; D020641:Polymorphism, Single Nucleotide; D012480:Salmonella Infections / Q000453:epidemiology* / Q000382:microbiology*; D019779:Salmonella enterica / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D065288:Serogroup; D055815:Young Adult