The lytic transglycosylase MltB connects membrane homeostasis and in vivo fitness of Acinetobacter baumannii

• DOI: 10.1111/mmi.14000
• Publication Date: 2018-06-09T06:44:54Z
• Authors: Sébastien Crépin; Elizabeth N. Ottosen; Katharina Peters; Sara N. Smith; Stephanie D. Himpsl; Waldemar Vollmer; Harry L. T. Mobley
• Keywords: Acinetobacter baumannii; Lytic cycle; Regulon; Cell envelope

Summary Acinetobacter baumannii has emerged as a leading nosocomial pathogen, infecting wide range of anatomic sites including the respiratory tract and bloodstream. In addition to being multi‐drug resistant, little is known about molecular basis A. pathogenesis. To better understand A . virulence, combination transposon‐sequencing (TraDIS) screen neutropenic mouse model bacteremia was used identify full set fitness genes required during bloodstream infection. The lytic transglycosylase MltB identified critical factor. cleaves Mur N Ac‐Glc Ac bond peptidoglycan, which leads cell wall remodeling. Here we show that part complex network connecting resistance stresses, membrane homeostasis, biogenesis pili in vivo fitness. Indeed, inactivation mltB not only impaired serum complement, cationic antimicrobial peptides oxygen species, but also altered envelope integrity, activated stress response, drastically reduced number at surface finally, significantly decreased colonization both tract.