Capsular Polysaccharide Is Essential for the Virulence of the Antimicrobial-Resistant Pathogen Enterobacter hormaechei
Amelia St. John, Andrew I. Perault, Sabrina I. Giacometti, Alexis G. Sommerfield, Ashley Dumont, Keenan A. Lacey, Xuhui Zheng, Julia Sproch, Chris Petzold, Kristen Dancel-Manning, Sandra González, Medini K. Annavajhala, Colleen Beckford, Nathalie E. Zeitouni, Feng‐Xia Liang, Harm van Bakel, Bo Shopsin, Anne‐Catrin Uhlemann, Alejandro Pironti, Victor J. Torres
Abstract
Infections caused by antimicrobial resistant bacteria are of increasing concern, especially those due to carbapenem-resistant Enterobacteriaceae pathogens. Included in this group are species of the Enterobacter cloacae complex, regarding which there is a paucity of knowledge on the infection biology of the pathogens, despite their clinical relevance. In this study, we combine techniques in comparative genomics, bacterial genetics, and diverse models of infection to establish capsule as an important mechanism of Enterobacter pathogens to resist the antibacterial activity of serum, a first line of host defense against bacterial infections. We also show that immune memory targeting the Enterobacter capsule protects against lethal infection. The further characterization of Enterobacter infection biology and the immune response to infection are needed for the development of therapies and preventative interventions targeting these highly antibiotic resistant pathogens.