Boron–Diol Chemistry in Marine Systems: Biological Interfaces, Microbial Communication, and Therapeutic Potential

Boron is widely distributed in marine and biological systems, particularly in seawater, where it exists in dynamic equilibrium between boric acid and borate, yet its functional roles remain incompletely understood. Unlike transition metals, boron does not form stable coordination complexes under physiological conditions but instead engages in reversible interactions with cis-diol-containing biomolecules, including carbohydrates, ribose derivatives, and catechol-based metabolites. In marine environments, where diol-rich polysaccharides, biofilms, and glycoconjugates are abundant, this chemistry is especially relevant at biological interfaces. Here, we propose that such dynamic boron–diol interactions enable boron to function as a molecular architect of glycan-rich interfaces. We develop a unifying framework in which borate-mediated coordination transiently links carbohydrate and amphiphilic domains, generating reversible amphiphile–carbohydrate assemblies that respond to environmental conditions. These processes provide a mechanistic basis for adaptive interfacial organization in marine systems, including microbial biofilms, host-associated microbiota, and mucosal-like surfaces. Extending this concept, boron-mediated interactions may also influence siderophore activity and microbial communication in marine ecosystems. From a biomedical perspective, these interface-regulating properties suggest potential roles for boron-containing systems in modulating biofilms, host–microbe interactions, and disease-related processes. Furthermore, we propose that similar mechanisms may have contributed to early evolution, facilitating the coupling of simple sugars with primitive amphiphiles and promoting the emergence of protomembrane structures prior to the development of covalently defined lipid membranes. This perspective reframes boron as a dynamic mediator of molecular organization across marine and biological systems, operating within a transient coordination layer that remains largely inaccessible to conventional biochemical analysis.