Acinetobactin–ferric complex (Fe-acinetobactin) (Fe-acinetobactin)

The acinetobactin–ferric complex is a coordination compound formed when the siderophore acinetobactin, secreted by the opportunistic pathogen Acinetobacter baumannii, binds to trivalent iron (Fe3+) in the extracellular environment (Yamamoto et al., 1994). This complex is essential for the survival of A. baumannii within the host, where iron availability is strictly limited by host proteins like transferrin and lactoferrin (Zimbler et al., 2009). The complex is specifically recognized by the outer membrane receptor BauA, which facilitates its transport into the bacterial periplasm in a TonB-dependent manner (Penwell et al., 2012). Because this pathway is vital for bacterial growth and virulence, it has become a primary focus for the development of "Trojan Horse" antibiotics. These therapeutic strategies involve conjugating antimicrobial agents to acinetobactin or its analogs to ensure efficient uptake into highly resistant bacterial cells (Shizagochi et al., 2018). Consequently, the acinetobactin–ferric complex and its associated transport machinery represent critical targets for overcoming multi-drug resistance in clinical settings. Understanding the structural dynamics of this complex is crucial for designing effective siderophore-mimetic drugs that can bypass traditional resistance mechanisms.

Other names

Ferric-acinetobactinFe(III)-acinetobactinIron-acinetobactin complex

Siderophore-mediated active transport via the BauA receptor (Trojan Horse strategy)