VxrB Influences Antagonism within Biofilms by Controlling Competition through Extracellular Matrix Production and Type 6 Secretion
Jennifer K. Teschler, Eva Jiménez‐Siebert, Hannah Jeckel, Praveen K. Singh, Jin Hwan Park, Stefan Pukatzki, Carey D. Nadell, Knut Drescher, Fitnat H. Yildiz
Abstract
This work demonstrates that the Vibrio cholerae type six secretion system (T6SS) can actively kill prey strains within the interior of biofilm populations with substantial impact on population dynamics. We additionally show that the response regulator VxrB contributes to both T6SS killing and protection from T6SS killing within biofilms. Components of the biofilm matrix and the degree of spatial mixing among strains also strongly influence T6SS competition dynamics. T6SS killing within biofilms results in increased localized release of extracellular DNA, which serves as an additional matrix component. These findings collectively demonstrate that T6SS killing can contribute to competition within biofilms and that this competition depends on key regulators, matrix components, and the extent of spatial population mixture during biofilm growth.