In Vivo and In Vitro Protein–Peptidoglycan Interactions

  • Gang Li
  • S. Peter HowardEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1615)


Bacteria have developed a number of trans-envelope systems to transport molecules or assemble organelles across bacterial envelopes. However, bacterial envelopes contain a rigid netlike peptidoglycan structure that protects cells from osmotic lysis. Trans-envelope systems thus must interact with the peptidoglycan barrier to generate gaps or anchor structures to the peptidoglycan scaffold. Here we describe methods to use in vivo cross-linking and in vitro co-sedimentation to study protein–peptidoglycan interactions in Gram-negative bacteria. In particular, we address important considerations to ensure the specificity of the interactions in question.

Key words

Trans-envelope systems Peptidoglycan Cross-linking Co-sedimentation Muramic acid assay 


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Copyright information

© Springer Science+Business Media LLC 2017

Authors and Affiliations

  1. 1.Department of Microbiology and ImmunologyCollege of Medicine, University of SaskatchewanSaskatoonCanada

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