TITLE:
Use of LPS Extracts to Validate Phage Oligopeptide That Binds All Salmonella enterica Serovars
AUTHORS:
I-Hsuan Chen, Kiril Vaglenov, Yating Chai, Bryan A. Chin, James M. Barbaree
KEYWORDS:
LPS Extractions, Phage Display, Salmonella, Biosensors
JOURNAL NAME:
Advances in Microbiology,
Vol.4 No.9,
July
28,
2014
ABSTRACT: Phage Display technology provides a mechanism for
us to make bio-recognition elements on biosensors for detection of Salmonella
enterica serovars. In the procedure, the filamentous M13 bacteriophage is
used for acquiring peptides that have a high affinity for the target
recognition. Our approach in this study was to develop peptide structures in
the pIII region of this thread-shaped virus. A phage pIII library was used to
perform biopanning for the phage clones to bind the target Salmonella serovars. The clones were bound, washed, eluted and
amplified four times. Then, the phage peptides were sequenced tested for
specificity using ELISA procedures. In this project to make a biosensor
for all relevant Salmonella enterica serovars, we used common LPS
salmonellae antigens as targets in the biopanning procedure. This enabled us to
have a phage probe specific for all serovars of Salmonella enterica excluding the typhoid organisms. The final phage was then immobilized onto an
electromagnetic platform to complete the biosensor, which gives us the real-time
ability to measure resonance changes that indicate mass loading. The mass loading
is an indication of binding to the target cells. Our current data with an ELISA
procedure show the phage probe’s high affinity for salmonellae, very low
cross-reactivity with Escherichia coli, Shigella, and no cross-reactivity to Staphylococcus
aureus and Listeria monocytogenes. The biosensor with the phage
showed that the capture ability for Salmonella serovars is thirty times
higher than the control sensor. This biosensor is a candidate for detection of Salmonella in food and other settings.