Emergence of resistance against drugs viz. carbapenems, fluoroquinolones, aminoglycosides is the major problem associated with Acinetobacter baumannii infections thus making it imperative to develop a suitable vaccine as an effective treatment option. Previous studies reveal that outer membrane proteins of A. baumannii could serve as vaccine candidates and provide partial or complete immunity against lethal doses in various mouse models. Recently, we have shown reverse vaccinology as a powerful tool to identify vaccine candidates. The immunoprotective efficacy of an outer membrane, putative pilus assembly protein, FilF, identified as a potential vaccine candidate was validated in A. baumannii associated murine pneumonia model and was found to provide 50% survival against A. baumannii lethal doses. NucAb, an outer membrane nuclease identified in silico as A. baumannii vaccine candidate, provided 20% survival on active and 40% survival on passive immunization.