Antibiotic resistance is a major cause for concern in modern healthcare with increasingly difficult to treat 'Superbug' infections. In particular, carbapenem-resistant Acinetobacter baumannii is categorized as an urgent threat by the Centre for Disease Control (CDC) and a top priority for drug development by the World Health Organization (WHO). Thus, identification of novel targets and the development of new therapeutics against this Gram-negative pathogen is urgently required. Bacterial fatty acid biosynthesis (Fab) enzymes, particularly the reductases FabG and FabI, present attractive targets for inhibitors. In the present study, both a low-molecular weight and high-molecular weight FabG homolog were structurally characterized with distinct architecture and coenzyme preference. To date, this is the second bacterial high-molecular weight FabG structurally characterized following FabG4 from Mycobacterium. This enzyme may contribute to Acinetobacter survival and success as a pathogen, making it a potential target for therapeutic development.