Transcriptomic insights into the virulence of Acinetobacter baumannii during infection-role of iron uptake and siderophore production genes

FEBS Lett. 2024 Nov 21. doi: 10.1002/1873-3468.15061. Online ahead of print.

Abstract

Acinetobacter baumannii, a top-priority WHO pathogen, causes life-threatening infections in immunocompromised patients, leading to prolonged hospitalisation and high mortality. Here, we used the Galleria mellonella model to investigate community strain C98 (Ab-C98) virulence via transcriptomic analysis. Ab-C98 showed greater killing and faster colonisation in larvae than the clinical reference strain (ATCC BAA1605). Genes in three iron clusters, acinetobactin, baumannoferrin and the Feo system, were significantly up-regulated. Targeted knockout of siderophore genes (basC, bfnD, and the gene encoding isochorismatase) significantly increased the survival of infected larvae by at least 35.16%, identifying these genes as potential targets for developing anti-virulence agents against A. baumannii.

Keywords: Acinetobacter baumannii; Direct RNA sequencing; Galleria mellonella; siderophore; virulence.