Cable bacteria-mediated electromicrobial interactions: Mechanisms, ecological effects, and biotechnological prospects

Cable bacteria are filamentous microorganisms with the unique ability to conduct electrons over centimeter-scale distances, thereby coupling spatially separated sulfide oxidation and oxygen reduction in sediments. Recent research confirms that these organisms not only perform extracellular electron transfer (EET) but also act as "biological conduits", mediating electromicrobial interactions with other microorganisms and thus forming complex networks of electroactive microbial communities. In light of these findings, this review systematically synthesizes the core mechanisms of cable bacteria-mediated electromicrobial interactions, including the structural basis for electrical conductivity, interaction modes with flocking bacteria, the regulatory role of electron shuttles, and the synergistic effects of conductive materials. The adaptive strategies of cable bacteria and their associated communities under environmental stresses, including oxygen fluctuation, sulfide limitation, salinity variation, and physical disturbance, are summarized. We further explore the ecological effects driven by these interactions, such as the coupled cycling of sulfur, carbon, iron, and phosphorus, as well as plant-microbe symbiosis. Finally, we discuss prospects for their application in bioelectrosynthesis, particularly in pollutant degradation and optimization of microbial fuel cells. This review aims to elucidate core function of cable bacteria as "electron hubs" in ecosystems, thereby providing novel perspectives for field of electromicrobiology.