Current Microbiology

, Volume 76, Issue 12, pp 1467–1476 | Cite as

Identification and Characterization of Cronobacter Strains Isolated from Environmental Samples

  • Jinrui Hu
  • Xiaofang Li
  • Xiaoli Du
  • Zhigang Cui
  • Jinghua CuiEmail author


As an emerging food-borne pathogen, Cronobacter species are ubiquitous in the food and environment. In order to know the characteristics of Cronobacter spp. from the environment, we isolated Cronobacter spp. from soil and water, and then studied the molecular typing and antibiotic resistance characteristics of these isolates. In 2016, 141 soil and water samples were collected from farms and Riverside Park in Beijing. Isolates were identified by real-time PCR, 16s rRNA sequencing, and whole-genome sequencing. Molecular subtyping of these isolates was characterized by pulsed-field gel electrophoresis, multilocus sequence typing (MLST), and antibiotic susceptibility tests. Cronobacter species were classified based on fusA sequencing. Twenty-two samples (15.60%) contained Cronobacter spp., and four species were detected, i.e., C. dubliniensis (n = 10), C. sakazakii (n = 6), C. turicensis (n = 4), and C. malonaticus (n = 2). For MLST, 12 types (ST519–ST525, ST533–ST537) were newly identified, indicating high diversity. Most isolates (68.18%) showed resistance to cefazolin. Siccibacter turicensis and Cronobacter both with blue-green colonies on selective media should be respectively identified. Apparently, major Cronobacter species in soil and water samples differed from those in food. Molecular subtyping showed that the environment could not be excluded as a source of Cronobacter infection. The resistance to cefazolin of most isolates indicated natural resistance.



This study was supported by the National Natural Science Foundation of China (81501799) and the National Science and Technology Key Project of China.

Compliance with Ethical Standards

Conflicts of interest

The authors declare no conflict of interest.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Jinrui Hu
    • 1
  • Xiaofang Li
    • 2
  • Xiaoli Du
    • 1
  • Zhigang Cui
    • 1
  • Jinghua Cui
    • 1
    • 3
    Email author
  1. 1.State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseaseNational Institute for Communicable Disease Control and PreventionBeijingChina
  2. 2.Shanxi Key Laboratory of Stem Cell for Immunological Dermatosis, Institute of DermatologyTaiyuan City Center HospitalTaiyuanChina
  3. 3.Department of BacteriologyCapital Institute of PediatricsBeijingChina

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