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Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes
14:05

Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes

Published on: September 19, 2013

10.4K

A structural comparison of Listeria monocytogenes protein chaperones PrsA1 and PrsA2 reveals molecular features

Laty A Cahoon1, Nancy E Freitag1, Gerd Prehna1,2

  • 1Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL.

Molecular Microbiology
|March 24, 2016
PubMed

Insights

PrsA1 and PrsA2 are bacterial chaperones. PrsA2 aids Listeria monocytogenes virulence, while PrsA1 provides alcohol resistance, revealing multifaceted roles for these proteins.

Area of Science:

  • Microbiology
  • Structural Biology
  • Biochemistry

Background:

  • Listeria monocytogenes is a Gram-positive bacterium that transitions from an environmental soil dweller to a mammalian pathogen.
  • Pathogenicity relies on secreted virulence factors for cell invasion and intracellular growth.
  • PrsA1 and PrsA2 are secreted lipoprotein chaperones involved in protein folding across the bacterial membrane; PrsA2 is crucial for virulence, but PrsA1's function is unknown.

Purpose of the Study:

  • To elucidate the structural and functional roles of PrsA1 and PrsA2 in Listeria monocytogenes.
  • To investigate the contribution of PrsA2 oligomerization and foldase domain to virulence.
  • To determine the specific function of PrsA1.

Main Methods:

  • X-ray crystallography was used to determine the structure of PrsA1.
  • Structure-based mutagenesis was employed to study PrsA2.
  • Comparative analysis of PrsA1 and PrsA2 structures and functions.

Main Results:

  • The X-ray crystal structure of PrsA1 was solved.
  • Mutagenesis studies revealed PrsA2 oligomerization and foldase domain are essential for protein secretion and virulence.
  • PrsA1 was found to play a role in bacterial resistance to alcohol.
  • PrsA2 retained function even when not localized to the membrane.

Conclusions:

  • PrsA chaperones possess distinct domains enabling diverse functions.
  • PrsA2's oligomerization and foldase domain are critical for L. monocytogenes virulence.
  • PrsA1 has a novel role in alcohol resistance, highlighting functional divergence within the PrsA family.

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