UNIGE document Scientific Article
previous document  unige:18937  next document
add to browser collection
Title

Role of magnesium and a phagosomal P-type ATPase in intracellular bacterial killing

Authors
Molmeret, Maëlle
show hidden authors show all authors [1 - 9]
Published in Cellular Microbiology. 2011, vol. 13, no. 2, p. 246-58
Abstract Bacterial ingestion and killing by phagocytic cells are essential processes to protect the human body from infectious microorganisms. However, only few proteins implicated in intracellular bacterial killing have been identified to date. We used Dictyostelium discoideum, a phagocytic bacterial predator, to study intracellular killing. In a random genetic screen we identified Kil2, a type V P-ATPase as an essential element for efficient intracellular killing of Klebsiella pneumoniae bacteria. Interestingly, kil2 knockout cells still killed efficiently several other species of bacteria, and did not show enhanced susceptibility to Mycobacterium marinum intracellular replication. Kil2 is present in the phagosomal membrane, and its structure suggests that it pumps cations into the phagosomal lumen. The killing defect of kil2 knockout cells was rescued by the addition of magnesium ions, suggesting that Kil2 may function as a magnesium pump. In agreement with this, kil2 mutant cells exhibited a specific defect for growth at high concentrations of magnesium. Phagosomal protease activity was lower in kil2 mutant cells than in wild-type cells, a phenotype reversed by the addition of magnesium to the medium. Kil2 may act as a magnesium pump maintaining magnesium concentration in phagosomes, thus ensuring optimal activity of phagosomal proteases and efficient killing of bacteria.
Keywords Adenosine Triphosphatases/metabolismDictyostelium/metabolism/microbiologyKlebsiella pneumoniae/drug effects/growth & developmentMagnesium/metabolismMembrane Transport Proteins/genetics/metabolismMicrobial Viability/drug effectsMycobacterium marinum/drug effects/growth & developmentPhagosomes/metabolism/microbiologyProtozoan Proteins/genetics/metabolism
Identifiers
PMID: 21040356
Full text
Article (Published version) (935 Kb) - public document Free access
Structures
Research group Phagocytose (140)
Citation
(ISO format)
LELONG-FAVRE ALBORINI, Emmanuelle et al. Role of magnesium and a phagosomal P-type ATPase in intracellular bacterial killing. In: Cellular Microbiology, 2011, vol. 13, n° 2, p. 246-58. https://archive-ouverte.unige.ch/unige:18937

315 hits

197 downloads

Update

Deposited on : 2012-03-20

Export document
Format :
Citation style :