MntABC and MntH contribute to systemic Staphylococcus aureus infection by competing with calprotectin for nutrient manganese

Infect Immun. 2013 Sep;81(9):3395-405. doi: 10.1128/IAI.00420-13. Epub 2013 Jul 1.

Abstract

During infection, vertebrates limit access to manganese and zinc, starving invading pathogens, such as Staphylococcus aureus, of these essential metals in a process termed "nutritional immunity." The manganese and zinc binding protein calprotectin is a key component of the nutrient-withholding response, and mice lacking this protein do not sequester manganese from S. aureus liver abscesses. One potential mechanism utilized by S. aureus to minimize host-imposed manganese and zinc starvation is the expression of the metal transporters MntABC and MntH. We performed transcriptional analyses of both mntA and mntH, which revealed increased expression of both systems in response to calprotectin treatment. MntABC and MntH compete with calprotectin for manganese, which enables S. aureus growth and retention of manganese-dependent superoxide dismutase activity. Loss of MntABC and MntH results in reduced staphylococcal burdens in the livers of wild-type but not calprotectin-deficient mice, suggesting that these systems promote manganese acquisition during infection. During the course of these studies, we observed that metal content and the importance of calprotectin varies between murine organs, and infection leads to profound changes in the anatomical distribution of manganese and zinc. In total, these studies provide insight into the mechanisms utilized by bacteria to evade host-imposed nutrient metal starvation and the critical importance of restricting manganese availability during infection.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism
  • Food
  • Leukocyte L1 Antigen Complex / metabolism*
  • Manganese / metabolism*
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism
  • Metals / metabolism
  • Mice
  • Staphylococcal Infections / genetics
  • Staphylococcal Infections / metabolism*
  • Staphylococcus aureus / genetics
  • Staphylococcus aureus / metabolism*
  • Superoxide Dismutase / genetics
  • Superoxide Dismutase / metabolism
  • Transcription, Genetic

Substances

  • Bacterial Proteins
  • Carrier Proteins
  • Leukocyte L1 Antigen Complex
  • Membrane Transport Proteins
  • Metals
  • zinc-binding protein
  • Manganese
  • Superoxide Dismutase