Abstract
AbstractThe evolutionary relationship between the biofilm lifestyle and antibiotic resistance enzymes remains a subject of limited understanding. Here, we investigate how β-lactamases affect biofilm formation inVibrio choleraeand how selection for a biofilm lifestyle impacts the evolution of these enzymes. Seven genetically diverse β-lactamases expressed inV. choleraedisplayed a strong inhibitory effect on biofilm production, ranging from 17% to 61%. To understand how natural evolution affects this antagonistic pleiotropy under biofilm selecting conditions, we randomly mutagenized one β-lactamase and selected for elevated biofilm formation. Our results revealed that biofilm evolution selects for mutations predominantly clustered around the β-lactamase’s active site, yielding functional variants still proficient in β-lactam hydrolysis without biofilm inhibition. Mutational analysis of evolved variants demonstrated that restoration of biofilm development could be achieved either independent of enzymatic function or by actively leveraging enzymatic activity to increase biofilm formation. Taken together, the biofilm lifestyle can impose a profound selective pressure on antimicrobial resistance enzymes. Shedding light on such evolutionary interplays is of great importance to understand the various factors driving antimicrobial resistance.Impact statementβ-lactamases inhibit biofilm formation and the selection for increased biofilm production can mitigate this antagonistic pleiotropic effect. The emergence of β-lactamase variants avoiding biofilm inhibition strongly suggests that the biofilm lifestyle affects the evolutionary fate of these enzymes.
Publisher
Cold Spring Harbor Laboratory