Abstract
Acinetobacter baumannii is a Gram-negative coccobacillus and is a leading nosocomial pathogen worldwide. Recently, emergence of multidrug resistant A. baumannii has become a great threat to healthcare. Strains resist to the last line of anti-mocrobial agents, tigecycline and colistin, were appeared. Therefore, developing new drugs to treat A. baumannii infections is urgently needed. In this work, a human antimicrobial peptide LL-37 was evaluated for its effects on A. baumannii. We found that LL-37 kills A. baumannii efficiently and reduces cell adhesion and motility. Lipopolysaccharides extracted from A. baumannii cell surface can rescue LL37-mediated inhibition of cell adhesion. Moreover, far-western analysis indicated that LL-37 binds to outer membrane OmpA protein of A. baumannii (AbOmpA), but this binding seems not to correlate with the inhibitory effect on cell adhesion. However, both LPS and AbOmpA were related to sensitivity of A. baumannii to LL-37. Together, this study suggested that LL-37 may be a potential agent in the future treatment of A. baumannii infections.