title: Chemical, physical and morphological properties of bacterial biofilms affect survival of encased Campylobacter jejuni F38011 under aerobic stress.
abstract: Campylobacter jejuni is a microaerophilic pathogen and leading cause of human gastroenteritis. The presence of C. jejuni encased in biofilms found in meat and poultry processing facilities may be the major strategy for its survival and dissemination in aerobic environment. In this study, Staphylococcus aureus, Salmonella enterica, or Pseudomonas aeruginosa was mixed with C. jejuni F38011 as a culture to form dual-species biofilms. After 4days' exposure to aerobic stress, no viable C. jejuni cells could be detected from mono-species C. jejuni biofilm. In contrast, at least 4.7logCFU/cm2of viable C. jejuni cells existed in some dual-species biofilms. To elucidate the mechanism of protection mode, chemical, physical and morphological features of biofilms were characterized. Dual-species biofilms contained a higher level of extracellular polymeric substances with a more diversified chemical composition, especially for polysaccharides and proteins, than mono-species C. jejuni biofilm. Structure of dual-species biofilms was more compact and their surface was >8 times smoother than mono-species C. jejuni biofilm, as indicated by atomic force microscopy. Under desiccation stress, water content of dual-species biofilms decreased slowly and remained at higher levels for a longer time than mono-species C. jejuni biofilm. The surface of all biofilms was hydrophilic, but total surface energy of dual-species biofilms (ranging from 52.5 to 56.2mJ/m2) was lower than that of mono-species C. jejuni biofilm, leading to more resistance to wetting by polar liquids. This knowledge can aid in developing intervention strategies to decrease the survival and dispersal of C. jejuni into foods or environment.
authors.affiliation: Food, Nutrition, and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Jinsong
authors.initials: J
authors.lastname: Feng
authors.affiliation: Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Lamour
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Tianjin University of Science and Technology, Tianjin 300457, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Xue
authors.affiliation: Department of Chemical and Biological Engineering, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
authors.forename: Mehr Negar
authors.initials: MN
authors.lastname: Mirvakliki
authors.affiliation: Department of Chemical and Biological Engineering, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
authors.forename: Savvas G
authors.initials: SG
authors.lastname: Hatzikiriakos
authors.affiliation: Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL 60607, United States.
authors.forename: Jie
authors.initials: J
authors.lastname: Xu
authors.affiliation: Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada.
authors.forename: Hongbin
authors.initials: H
authors.lastname: Li
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Tianjin University of Science and Technology, Tianjin 300457, China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.affiliation: Food, Nutrition, and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada. Electronic address: xiaonan.lu@ubc.ca.
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Lu
mesh_terms: D000332:Aerobiosis; D018441:Biofilms; D016123:Campylobacter jejuni / Q000737:chemistry / Q000254:growth & development* / Q000502:physiology; D006801:Humans; D050296:Microbial Viability; D011550:Pseudomonas aeruginosa / Q000737:chemistry / Q000254:growth & development / Q000502:physiology*; D019779:Salmonella enterica / Q000737:chemistry / Q000254:growth & development / Q000502:physiology*; D013211:Staphylococcus aureus / Q000737:chemistry / Q000254:growth & development / Q000502:physiology*
keywords: Atomic force microscopy; Confocal laser scanning microscopy; Contact angle measurement; Raman spectroscopy