Differential Susceptibility of Bacteria to Mouse Paneth Cell α-Defensins under Anaerobic Conditions

Antibiotics

Jennifer R. Mastroianni²  Wuyuan Lu¹  Michael E. Selsted²  André J. Ouellette² 

[1] Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Institute of Human Virology, Baltimore, MD 21201, USA; E-Mail:;Department of Pathology and Laboratory Medicine, Keck School of Medicine of the University of Southern California, USC Norris Cancer Center, Los Angeles, CA 90089-9601, USA; E-Mails:

关键词: antimicrobial peptide;    microbicide;    cryptdin;    facultative;    microbiota;    ileum;   

DOI  :  10.3390/antibiotics3040493

来源: mdpi

【 摘 要 】

Small intestinal Paneth cells secrete α-defensin peptides, termed cryptdins (Crps) in mice, into the intestinal lumen, where they confer immunity to oral infections and define the composition of the ileal microbiota. In these studies, facultative bacteria maintained under aerobic or anaerobic conditions displayed differential sensitivities to mouse α-defensins under in vitro assay conditions. Regardless of oxygenation, Crps 2 and 3 had robust and similar bactericidal activities against S. typhimurium and S. flexneri, but Crp4 activity against S. flexneri was attenuated in the absence of oxygen. Anaerobic bacteria varied in their susceptibility to Crps 2-4, with Crp4 showing less activity than Crps 2 and 3 against Enterococcus faecalis, and Bacteroides fragilis in anaerobic assays, but Fusobacterium necrophorum was killed only by Crp4 and not by Crps 2 and 3. The influence of anaerobiosis in modulating Crp bactericidal activities in vitro suggests that α-defensin effects on the enteric microbiota may be subject to regulation by local oxygen tension.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.