AUTHOR=Martínez-Guitián Marta , Vázquez-Ucha Juan C. , Álvarez-Fraga Laura , Conde-Pérez Kelly , Lasarte-Monterrubio Cristina , Vallejo Juan Andrés , Bou Germán , Poza Margarita , Beceiro Alejandro TITLE=Involvement of HisF in the Persistence of Acinetobacter baumannii During a Pneumonia Infection JOURNAL=Frontiers in Cellular and Infection Microbiology VOLUME=Volume 9 - 2019 YEAR=2019 URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2019.00310 DOI=10.3389/fcimb.2019.00310 ISSN=2235-2988 ABSTRACT=Acinetobacter baumannii is currently considered one of the most problematic nosocomial microorganisms. In the present work the hisF gene from the ATCC 17978 strain and the AbH12O-A2 clinical isolate of A. baumannii was found over-expressed during the course of murine pneumonia infections. The study demonstrated that the A. baumannii ATCC 17978 mutant strain lacking the hisF gene induces a sub-lethal pneumonia infection in mice, while the complemented mutant strain increased its virulence. This histidine auxotroph mutant showed an increase on IL-6 secretion and leukocytes recruitment during infections. Furthermore, data revealed that the hisF gene, implicated in the innate immunity and inflammation, is involved in virulence during a pneumonia infection, which may partly explain the ability of this strain to persist in the lung. We suggest that HisF, essential for full virulence in this pathogen, should be considered a potential target for developing new antimicrobial therapies against A. baumannii.