Functional Plasticity of Microbial Siderophores in Iron- and Boron-Rich Niches

Functional Plasticity of Microbial Siderophores in Iron- and Boron-Rich Niches Review

Journal

Applied Microbiology
ISSN: 2673-8007

Output data

Year: 2026, Volume: 6, Number: 4, Article number : 50, Pages count : DOI: 10.3390/applmicrobiol6040050

Authors

Dembitsky Valery M. ^1,2 , Terent’ev Alexander O. ² , Baranin Sergey V. ²

Affiliations

1	Bio-Pharm Laboratories, 23615 El Toro Rd X, Lake Forest, CA 92630, USA
2	N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky Prospect, Moscow 119991, Russia

Siderophores are high-affinity iron-chelating metabolites that underpin microbial survival in iron-limited environments and play central roles in metal homeostasis, ecological competition, and pathogenesis. Traditionally viewed as dedicated Fe(III) scavengers, siderophores are now recognized as structurally and functionally versatile coordination agents whose donor-set architectures—particularly catecholate and α-hydroxycarboxylate motifs—permit conditional interactions beyond iron. In iron- and boron-rich niches, especially marine and mildly alkaline systems where borate availability increases, certain siderophores are chemically capable of forming reversible borate complexes through cis-diol coordination. Although Fe(III) exhibits substantially higher thermodynamic affinity and remains the primary biological target, boron binding represents a predictable secondary property arising from shared oxygen-donor chemistry. This dynamic interplay allows siderophores to cycle between iron-bound, boron-bound, and apo states depending on local redox conditions, pH, and metal availability. Here, we synthesize current knowledge on the structural classes of microbial siderophores, their transport and regulatory mechanisms, and emerging evidence for boron coordination within catecholate and carboxylate systems. By integrating coordination chemistry with microbial ecology, we propose an expanded model in which siderophores function not only as iron acquisition molecules but also as modulators of boron speciation and environmental sensing. This functional plasticity positions siderophores at the intersection of iron and boron biogeochemical cycles and highlights new directions for understanding microbial adaptation in complex metal-rich environments.

Dembitsky V.M. , Terent’ev A.O. , Baranin S.V.
Functional Plasticity of Microbial Siderophores in Iron- and Boron-Rich Niches
Applied Microbiology. 2026. V.6. N4. 50 . DOI: 10.3390/applmicrobiol6040050 OpenAlex

Submitted:	Feb 22, 2026
Published online:	Mar 31, 2026

≡ OpenAlex:

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