Sulfur-Containing Microbial Natural Products and Their Role in Communal Interactions

Natural products remain a primary source of new chemical entities and a central medium of biological communication. Among them, sulfur-containing natural products from microbes stand out for their diverse motifs─such as thioether (S-Cα/β/γ), thiazole, and sulfonate groups─distributed across RiPPs, NRPs, PKs, lipids, terpenoids, and hybrids. These sulfur-containing metabolites functionally contribute to communal interactions─intra- and interspecies microbe-microbe and microbe-host interactions─through their antibacterial, antifungal, antiviral, anticancer, and immunomodulatory activities. Crucially, they may act as information-rich signals that tune quorum circuits, biofilms, membrane and ion homeostasis, and host pathways. This review provides a structure- and mechanism-guided overview of sulfur-containing natural products reported over the past decade (2014-2025), covering their microbial sources, chemical diversity, as well as mechanisms of action and emphasizing how sulfur functionality encodes interaction strategies from host microbiomes to environmental systems.