Backbone assignment of the OmpA-like domain of peptidoglycan-associated lipoprotein from Acinetobacter baumannii

Acinetobacter baumannii is a multidrug-resistant opportunistic pathogen which induces the cytotoxicity of host cells by nosocomial infections. Peptidoglycan-associated lipoprotein (Pal) is one component of Tol-Pal system, which is involved in maintaining the integrity and stability of the outer membrane (OM) as well as the virulence of bacterial pathogens. Pal is composed of N-terminal hydrophobic domain anchoring to the OM and C-terminal OmpA-like domain interacting with peptidoglycan. Herein, we report the preparation of protein sample and the backbone assignment of recombinant OmpA-like domain of Pal protein from Acinetobacter baumannii (AbPal-71). All the backbone chemical shifts of AbPal-71 (Cα, Cβ, CO, HN, and N) were completely assigned and the secondary structure was estimated from the assigned chemical shifts. This result shows that AbPal-71 is a typical OmpA-like fold, which consists of three α-helices and four β-strands. Based on this NMR spectroscopic results, the three dimensional structural study and the interaction study between AbPal-71 and peptidoglycan are in progress.