Dietary manganese promotes staphylococcal infection of the heart

Lillian J. Juttukonda, Evelien T.M. Berends, Joseph P. Zackular, Jessica L. Moore, Matthew T. Stier, Yaofang Zhang, Jonathan E. Schmitz, William N. Beavers, Christiaan D. Wijers, Benjamin A. Gilston, Thomas E. Kehl-Fie,James Atkinson, Mary K. Washington, R. Stokes Peebles, Walter J. Chazin, Victor J. Torres, Richard M. Caprioli, and Eric P. Skaar

Cell Host & Microbe 22, 531–542, October 11, 2017

Speaker: Yu-Shan Lin (林鈺珊)                        Time: 13:00~14:00, May. 09, 2018

Commentator: Ching-Hao Teng (鄧景浩 老師)          Place: Room 601

Abstract:

   Staphylococcus aureus is a gram-positive, round-shaped bacterium and is the leading cause of bacterial endocarditis. During infection, S. aureus encodes two major Mn acquisition system mntH and mntABC to acquire Mn for full virulence [1]. However, the impact of dietary Mn on S. aureus infection is unknown. In previous study, they found out that chelation of divalent cation (Mn²⁺, Zn²⁺ Fe²⁺) by calprotectin inhibits bacterial growth in vitro [2]. The authors aimed to determine how dietary Mn affect the outcome of S. aureus infection and to define the ability of the only known Mn-sequestering protein calprotectin, in limiting the impact of high diet Mn on infection. First, they found out that excess dietary Mn enhance S. aureus virulence and promotes growth of S. aureus in the heart but not in the liver or kidney. Interestingly, the calprotectin does not restrict S. aureus access Mn in the heart, contractually, it would promote S. aureus infection in the heart. Finally, the authors pointed out that S. aureus would utilize dietary Mn to defense superoxide stress and neutrophil killing. This paper suggest that a single dietary Mn could overwhelm host antimicrobial strategies to cause severe S. aureus infection. Furthermore, they also figure out that calprotectin sequesters Mn during S. aureus infection may exist a tissue-specific mechanism. 

References：

1. Horsburgh, M.J., Wharton, S.J., Karavolos, M., and Foster, S.J. (2002). Manganese: elemental defence for a life with oxygen. Trends. Microbiol. 10, 496–501.

2. Palmer, L.D., and Skaar, E.P. (2016). Transition metals and virulence in bacte- ria. Ann. Rev. Genet. 50, 67–91.