Increasing the Affinity of an O-Antigen Polysaccharide Binding Site in Shigella flexneri Bacteriophage Sf6 Tailspike Protein.
Sonja KunstmannOlof EngströmMarko WehleGöran WidmalmMark SanterStefanie BarbirzPublished in: Chemistry (Weinheim an der Bergstrasse, Germany) (2020)
Broad and unspecific use of antibiotics accelerates spread of resistances. Sensitive and robust pathogen detection is thus important for a more targeted application. Bacteriophages contain a large repertoire of pathogen-binding proteins. These tailspike proteins (TSP) often bind surface glycans and represent a promising design platform for specific pathogen sensors. We analysed bacteriophage Sf6 TSP that recognizes the O-polysaccharide of dysentery-causing Shigella flexneri to develop variants with increased sensitivity for sensor applications. Ligand polyrhamnose backbone conformations were obtained from 2D 1 H,1 H-trNOESY NMR utilizing methine-methine and methine-methyl correlations. They agreed well with conformations obtained from molecular dynamics (MD), validating the method for further predictions. In a set of mutants, MD predicted ligand flexibilities that were in good correlation with binding strength as confirmed on immobilized S. flexneri O-polysaccharide (PS) with surface plasmon resonance. In silico approaches combined with rapid screening on PS surfaces hence provide valuable strategies for TSP-based pathogen sensor design.
Keyphrases
- molecular dynamics
- candida albicans
- density functional theory
- loop mediated isothermal amplification
- biofilm formation
- magnetic resonance
- high resolution
- mass spectrometry
- molecular docking
- high throughput
- gene expression
- water soluble
- copy number
- dna methylation
- staphylococcus aureus
- label free
- small molecule
- real time pcr
- dna binding
- drug delivery
- protein protein