PROJECT SUMMARY/ABSTRACT Protein toxins and effectors are primary virulence factors of many bacterial pathogens. They cause diseases by targeting and disrupting key cellular functions. Historically, research on toxins/effectors has focused on only a few major toxins, which has achieved tremendous successes in establishing the framework of their mechanisms and in eradicating many devastating infectious diseases. Building on these earlier successes, the field has gone through a great resurgence and expansion in the past 20 years, transforming from a narrow focus on a few human diseases to much broader areas of biology, centering on understanding “protein-based” fight-and- defense communications between co-evolving organisms. For instance, recent advances in microbial genomics and discovery-based screening approaches have led to a dramatic increase in the number of toxins and effector systems being studied. New research has also revealed that microbes secrete and inject toxins and effectors not only to target eukaryotic cells during pathogenesis, but also to engage in interbacterial competition. Technological advances in high-resolution microscopy, structural biology, cryo-electron microscopy, proteomics, and CRISPR have rapidly advanced our understanding of toxins/effectors action. Despite the growth of both the depth and breadth of the field, there is currently no meeting in North America centered on toxins/effectors that can bring people together from diverse fields. To address this gap, we are launching a reconfigured and reimagined “in person-virtual” hybrid conference, “Lakeside Conference on Protein Toxins and Effectors” (#LakesidePTE) to be held October 3-6, 2021 at the Abbey Resort in Lake Geneva, Wisconsin, USA, leveraging the participation and enthusiastic feedback received during our inaugural meeting in October 2020, which was entirely on-line. This newly hybrid conference will focus on the cellular, structural, and biochemical mechanisms of protein toxin and effector action and the translation of these proteins for treatment of human disease. The conference will be organized by Chair Karla Satchell at Northwestern University and Vice-Chair Steven Blanke at University of Illinois at Urbana-Champaign. A ten member scientific advisory board will assist in selection of speakers and abstract review. There will be 5 sessions and three keynote addresses (Dr. Rod Welch from University of Wisconsin; Dr. Theresa Koehler from University of Texas-Houston, and Dr. Craig Roy from Yale University). Ten additional invited speakers will anchor five scientific sessions that will be filled out with talks selected from abstracts. Here we are seeking NIAID funds 1) to support registration fee and travel for keynote and invited speakers, (2) to offer registration scholarship awards for underrepresented minority post-docs and graduate students and (3) for audiovisual support for a hybrid meeting that will be simultaneously live streamed. This support from NI...