title: Production and evaluation of the utility of novel phage display-derived peptide ligands to Salmonella spp. for magnetic separation.
abstract: OBJECTIVE
  The objectives of this study were to produce Salmonella-specific peptide ligands by phage display biopanning and evaluate their use for magnetic separation (MS).
  
  
  RESULTS
  Four-phage display biopanning rounds were performed, and the peptides expressed by the two most Salmonella-specific (on the basis of phage-binding ELISA results) phage clones, MSal020401 and MSal020417, were chemically synthesized and coupled to MyOne™ tosylactivated Dynabeads(®). Peptide capture capability for whole Salmonella cells from nonenriched broth cultures was quantified by MS + plate counts and MS + Greenlight™ detection and compared to capture capability of anti-Salmonella (antibody-coated) Dynabeads(®). MS + Greenlight™ gave a more comprehensive picture of capture capability than MS + plate counts and showed that Peptide MSal020417-coated beads exhibited at least similar, if not better, capture capability to anti-Salmonella Dynabeads(®) (mean capture values of 36·0 ± 18·2 and 31·2 ± 20·1%, respectively, over Salmonella spp. concentration range 3 × 10(1) -3 × 10(6) CFU ml(-1)) with cross-reactivity of ≤1·9% to three other foodborne pathogens: Escherichia coli, Listeria monocytogenes and Campylobacter jejuni.
  
  
  CONCLUSIONS
  One of the phage display-derived peptide ligands was demonstrated by MS + Greenlight™ to be a viable antibody alternative for MS of Salmonella spp.
  
  
  CONCLUSIONS
  This study demonstrates an antibody-free approach to Salmonella detection and opens substantial possibilities for more rapid tests for this bacterium.
authors.affiliation: Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, UK.
authors.forename: J
authors.initials: J
authors.lastname: Morton
authors.forename: N
authors.initials: N
authors.lastname: Karoonuthaisiri
authors.forename: L D
authors.initials: LD
authors.lastname: Stewart
authors.forename: M
authors.initials: M
authors.lastname: Oplatowska
authors.forename: C T
authors.initials: CT
authors.lastname: Elliott
authors.forename: I R
authors.initials: IR
authors.lastname: Grant
mesh_terms: D061505:Cell Surface Display Techniques; D008024:Ligands; D060328:Magnetic Phenomena; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D012475:Salmonella / Q000302:isolation & purification*
chemical_list: D008024:Ligands; D010455:Peptides