Purple reign: the outsized impact and potential of Chromobacterium on quorum sensing research

Members of the Chromobacterium genus – instantly recognizable for their vivid purple pigment – have played a disproportionately influential role in shaping quorum sensing research. The discovery that violacein production in the model species Chromobacterium subtsugae is governed by an N -acyl

-homoserine lactone (AHL)-based LuxI/LuxR signalling system ignited a wave of breakthroughs in the field. With its genetic simplicity and visually striking phenotype, Chromobacterium emerged as a powerful and accessible model, enabling sensitive detection of AHLs across diverse bacteria and opening the door to fundamental insights into signalling promiscuity, interspecies communication and the molecular logic of quorum sensing pathways. In this review, we highlight both the foundational discoveries and ongoing contributions of the Chromobacterium genus, arguing that it has been central not only to the origins of AHL-based quorum sensing research but also to the field’s expansion towards increasingly sophisticated, community-level perspectives that continue to define its trajectory today – and into the future.