Open AccessMpn491, a secreted nuclease of Mycoplasma pneumoniae , plays a critical role in evading killing by neutrophil extracellular traps
Author(s) -
Yamamoto Takeshi,
Kida Yutaka,
Sakamoto Yuichi,
Kuwano Koichi
Publication year - 2017
Publication title -
cellular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.542
H-Index - 138
eISSN - 1462-5822
pISSN - 1462-5814
DOI - 10.1111/cmi.12666
Subject(s) - mycoplasma pneumoniae , neutrophil extracellular traps , biology , innate immune system , microbiology and biotechnology , nuclease , extracellular , immune system , in vitro , immunology , inflammation , enzyme , biochemistry , archaeology , history , pneumonia
Neutrophils play an important role in antimicrobial defense as the first line of innate immune system. Recently, the release of neutrophil extracellular traps (NETs) has been identified as a killing mechanism of neutrophils against invading microbes. Mycoplasma pneumoniae , a causative agent of respiratory infection, has been shown to be resistant to in vitro killing by neutrophils, suggesting that the bacterium might circumvent bactericidal activity of NETs. In this study, we investigated whether M. pneumoniae possesses resistance mechanisms against the NETs‐mediated killing of neutrophils and found that the bacterium degrades the NETs induced upon M. pneumoniae infection. The NETs‐degrading ability of M. pneumoniae required the production of a secreted nuclease, Mpn491, capable of using Mg 2 + as a cofactor for its hydrolytic activity. Moreover, the inactivation of the nuclease resulted in increased susceptibility of M. pneumoniae to the NETs‐mediated killing of neutrophils. The results suggest that M. pneumoniae employs Mpn491 as a means for evading the killing mechanism of neutrophils.