Quorum-Quenching Catalysts

University Of Texas At Austin, Austin TX

Investigators

Abstract

With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Walter Fast from University of Texas at Austin, and Dr. Dali Liu from Loyola University Chicago, to study enzymes capable of degrading N-acyl-homoserine lactones used in the quorum-sensing (QS) pathways of many Gram-negative bacteria. Two enzymes, one that uses a metal ion mediated mechanism (AiiA) and a second that uses covalent catalysis (PvdQ), will be investigated to determine how they recognize and process various QS signals. These enzymes will also be used to probe the QS and quorum-quenching in mixed microbial cultures. The results of this research will increase the precision of biochemical tools useful in quorum sensing research, will provide catalysts for potential anti-biofouling and anti-infective applications in agri-and aqua-culture, and will advance the understanding of social interactions between diverse bacterial species. Although bacteria are considered single-celled life, they display coordinated behaviors that are closely linked to how many individual bacteria are present in a given place. This type of group behavior is called "quorum-sensing" because some behaviors do not manifest until a quorum of bacteria is present. The goal of the proposal is to study proteins that can interfere with cell-to-cell signaling. This work will generate new catalysts with potential applications as industrial biofouling agents and as anti-infective agents in agri- and aqua-culture. The research will provide an environment for the training of graduate and undergraduate students in specialized techniques used in the study of protein structure and function. The project will also be integrated into an outreach program designed to increase the interest and participation in science of K-12 students. This award is co-funded by the Systems and Synthetic Biology Cluster in the Molecular and Cellular Biosciences (MCB) Division of the Biological Sciences (BIO) Directorate.