Elucidating the Dynamic Interactions of Borrelia burgdorferi Surface Proteins with Fibronectin using Atomic Force Microscopy

Lyme disease (LD) is the leading arthropod vector-borne illness, estimated at around 476,000 individuals diagnosed with LD each year in the USA. Borrelia burgdorferi (Bb), the leading bacterium in LD transmission throughout the northern United States, must adjust to the distinct environments of ticks and animals. The unique surface lipoproteins in Bb, which are found in the extracellular matrix (ECM), enable the bacterium to attach and integrate into its environment, responding to environmental prompts. The study suggests that Bb's ability to colonize tissues rich in ECM may serve as a potential mechanism of immune evasion. Our research investigates the adhesive properties of six specific proteins of Bb, RevA, BmpA, OspA, FlaB, OspC, and BBK32, by examining their interaction with the human protein Fn at the single-molecule level. By coating dishes with these proteins, we explored the interactions between Fn and specific proteins employing Atomic Force Microscopy equipped with functionalized cantilever tips using the Dynamic Force Spectroscopy technique. Our study uniquely quantifies the dynamic force interactions of these adhesins at varying loading rates. The study aims to understand the role of surface proteins in Lyme disease pathogenesis, and their mechanisms of action.