Elucidating the Stoichiometries of Host-Pathogen Protein Interactions with Mass Photometry

Emma-Jayne Proctor; Sandeep Satapathy; Martina Sanderson-Smith

doi:10.1007/978-1-0716-3243-7_13

Elucidating the Stoichiometries of Host-Pathogen Protein Interactions with Mass Photometry

Methods Mol Biol. 2023:2674:201-208. doi: 10.1007/978-1-0716-3243-7_13.

Authors

Emma-Jayne Proctor^{1

2}, Sandeep Satapathy^{3

4}, Martina Sanderson-Smith^{5

6}

Affiliations

¹ Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, Australia.
² Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia.
³ Blavatnik Institute of Cell Biology, Harvard Medical School, Boston, MA, USA.
⁴ The Broad Institute of MIT and Harvard, Cambridge, MA, USA.
⁵ Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, Australia. martina@uow.edu.au.
⁶ Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia. martina@uow.edu.au.

PMID: 37258969
DOI: 10.1007/978-1-0716-3243-7_13

Abstract

Mass photometry (MP) is a single molecule technique that enables the characterization of individual proteins. Here we show a detailed workflow using the Refeyn One^MP to investigate molecular complexes, using the M53 protein, a plasminogen-binding group A streptococcal M-like protein (PAM), and human plasminogen as exemplar proteins. The methodology described herein confirmed a 1:1 binding stoichiometry for the M53-plasminogen complex. Additionally, MP was used to identify the oligomerization state, homogeneity, purity, and approximate molecular weights of each protein.

Keywords: Binding stoichiometry; Host–pathogen interaction; M protein; Mass photometry; Oligomerization; PAM; Plasminogen; Polydispersity; Protein–protein; Refeyn.

MeSH terms

Bacterial Proteins* / metabolism
Carrier Proteins* / metabolism
Host-Pathogen Interactions
Humans
Photometry
Plasminogen / metabolism
Protein Binding
Streptococcus pyogenes / metabolism

Substances

Bacterial Proteins
Carrier Proteins
Plasminogen