P1-06 Rapid Association of Enteric Viruses with Whole Cell Bacteria in Suspension

Monday, July 10, 2017
Exhibit Hall (Tampa Convention Center)
Giselle Almeida , University of Arkansas , Fayetteville , AR
Kristen Gibson , University of Arkansas , Fayetteville , AR
Introduction: The association of enteric viruses such as human noroviruses (hNoV) with bacterial cells has been suggested as an important relationship for survival and perhaps infectivity. Viruses recognize various host cell receptors including histo-blood group antigens (HBGAs), and bacteria have been reported to express HBGA-like substances.

Purpose: This study aims to investigate the binding capacity of Tulane virus (TuV), murine norovirus (MNV), and Aichivirus (AiV) with whole cell bacteria at room temperature (RT).

Methods: Here, 400 µl of 107 PFU/ml AiV, 106 PFU/ml TuV, and 107 PFU/ml MNV were incubated individually with 109 CFU bacteria for up to two hours at RT. Bacteria used include Pantoea agglomerans, Pantoea ananatis, Enterobacter cloacae, Bacillus cereus, Pseudomonas spp., and Exiguobacterium sibiricum. Unbound viruses were recovered by filtration and detected by plaque assay using the corresponding host cells. Interaction of viruses with bacterial cells was visualized by transmission electron microscopy (TEM).

Results: Data suggest that both AiV and TuV readily associated with all bacterial species within 10 min at RT with complete viral association after two hours. There was a significant difference (P<0.0001) in the % mean of unbound TuV (29±15%) and AiV (3.7±2.0%) after 10 min, but no differences thereafter. There were also differences in binding activity to specific bacteria within virus type. For instance, % TuV not bound to E. sibiricum—a gram-positive lettuce isolate—was significantly higher than other bacteria at most time points. The same trend was observed with AiV as well as lower % binding of both viruses with B. cereus. TEM confirmed virus association with bacterial cells. MNV analysis is ongoing.

Significance: These data demonstrate a time dependent interaction of select cultivable viruses with both gram-negative and -positive bacterial cells. Understanding these interactions will allow further studies in the role these relationships play in virus survivability.