title: Immunomagnetic separation combined with colony immunoblotting for selective enrichment and detection of piliated Lactobacillus rhamnosus strains.
abstract: OBJECTIVE
  Piliated Lactobacillus rhamnosus (pLR) strains have attracted much attention owing to their excellent mucus adhering capacity and immunomodulatory effects. Here, we aimed to develop a rapid, sensitive method for isolating pLR strains in complex ecosystems using immunomagnetic separation (IMS) with colony immunoblotting (CIB).
  
  
  RESULTS
  Magnetic nanobeads (diameter: 180 nm) conjugated with anti-pLR SpaA pilin antibodies (anti-SpaA) were prepared and used to preconcentrate pLR strains in samples, followed by confirmation with anti-SpaA-based CIB analysis. Under optimized experimental conditions, IMS-CIB selectively recovered pLR strains from 107CFU ml-1of faecal microbiota samples spiked with 2·9 × 101to 2·4 × 106CFU ml-1of pLR strains. No positive colonies were detected in samples without addition of pLR strains. The detection limit of IMS-CIB was 29 CFU pLR ml-1of faecal microbiota, which is much lower than that of CIB without IMS preconcentration (2·0 × 104CFU ml-1).
  
  
  CONCLUSIONS
  IMS-CIB allowed selective preconcentration of pLR strains in highly heterogeneous bacterial suspensions and direct detection of pLR colonies, which remained readily available for subsequent isolation.
  
  
  CONCLUSIONS
  Our findings established an effective method for selective enrichment and detection of pLR strains.
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, China. yangzq@yzu.edu.cn.|Jiangsu Key Laboratory of Dairy Biotechnology and Safety Control, Yangzhou University, Yangzhou, Jiangsu, China. yangzq@yzu.edu.cn.|Jiangsu Key Laboratory of Zoonosis, Yangzhou, Jiangsu, China. yangzq@yzu.edu.cn.
authors.forename: Z Q
authors.initials: ZQ
authors.lastname: Yang
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, China.
authors.forename: Y F
authors.initials: YF
authors.lastname: Wei
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, China.
authors.forename: S Q
authors.initials: SQ
authors.lastname: Rao
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, China.
authors.forename: L
authors.initials: L
authors.lastname: Gao
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, China.
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Yin
authors.affiliation: Plant, Animal and Food Inspection Center, Jiangsu Entry-Exit Inspection and Quarantine Bureau, Nanjing, China. xuef1@jsciq.gov.cn.
authors.forename: F
authors.initials: F
authors.lastname: Xue
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, China.
authors.forename: W M
authors.initials: WM
authors.lastname: Fang
authors.affiliation: Jiangsu Key Laboratory of Dairy Biotechnology and Safety Control, Yangzhou University, Yangzhou, Jiangsu, China.
authors.forename: R X
authors.initials: RX
authors.lastname: Gu
authors.affiliation: Jiangsu Key Laboratory of Zoonosis, Yangzhou, Jiangsu, China.
authors.forename: X A
authors.initials: XA
authors.lastname: Jiao
mesh_terms: D005243:Feces / Q000382:microbiology; D015151:Immunoblotting; D018189:Immunomagnetic Separation; D052201:Lacticaseibacillus rhamnosus / Q000276:immunology / Q000302:isolation & purification*; D057230:Limit of Detection
keywords: 
  Lactobacillus rhamnosus
  ; colony immunoblotting; immunomagnetic separation; piliated strain; selective isolation