title: Deciphering Key Residues Involved in the Virulence-promoting Interactions betweenStreptococcus pneumoniaeand Human Plasminogen.
abstract: Bacterial pathogens recruit circulating proteins to their own surfaces, co-opting the host protein functions as a mechanism of virulence. Particular attention has focused on the binding of plasminogen (Plg) to bacterial surfaces, as it has been shown that this interaction contributes to bacterial adhesion to host cells, invasion of host tissues, and evasion of the immune system. Several bacterial proteins are known to serve as receptors for Plg including glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a cytoplasmic enzyme that appears on the cell surface in this moonlighting role. Although Plg typically binds to these receptors via several lysine-binding domains, the specific interactions that occur have not been documented in all cases. However, identification of the relevant residues could help define strategies for mitigating the virulence of important human pathogens, such asStreptococcus pneumoniae(Sp). To shed light on this question, we have described a combination of peptide-spot array screening, competition and SPR assays, high-resolution crystallography, and mutational analyses to characterize the interaction between SpGAPDH and Plg. We identified three SpGAPDH lysine residues that were instrumental in defining the kinetic and thermodynamic parameters of the interaction. Altogether, the integration of the data presented in this work allows us to propose a structural model for the molecular interaction of the SpGAPDH-Plg complex.
authors.affiliation: From the Institut de Biologie Structurale (IBS), Université Grenoble Alpes, Commissariat à l'Energie Atomique (CEA), CNRS, 38044 Grenoble, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Moreau
authors.affiliation: From the Institut de Biologie Structurale (IBS), Université Grenoble Alpes, Commissariat à l'Energie Atomique (CEA), CNRS, 38044 Grenoble, France.
authors.forename: Rémi
authors.initials: R
authors.lastname: Terrasse
authors.affiliation: From the Institut de Biologie Structurale (IBS), Université Grenoble Alpes, Commissariat à l'Energie Atomique (CEA), CNRS, 38044 Grenoble, France.
authors.forename: Nicole M
authors.initials: NM
authors.lastname: Thielens
authors.affiliation: From the Institut de Biologie Structurale (IBS), Université Grenoble Alpes, Commissariat à l'Energie Atomique (CEA), CNRS, 38044 Grenoble, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Vernet
authors.affiliation: From the Institut de Biologie Structurale (IBS), Université Grenoble Alpes, Commissariat à l'Energie Atomique (CEA), CNRS, 38044 Grenoble, France christine.gaboriaud@ibs.fr.
authors.forename: Christine
authors.initials: C
authors.lastname: Gaboriaud
authors.affiliation: From the Institut de Biologie Structurale (IBS), Université Grenoble Alpes, Commissariat à l'Energie Atomique (CEA), CNRS, 38044 Grenoble, France anne-marie.di-guilmi@ibs.fr.
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Di Guilmi
mesh_terms: D000595:Amino Acid Sequence; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D010958:Plasminogen / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D013296:Streptococcus pneumoniae / Q000472:pathogenicity*; D020349:Surface Plasmon Resonance; D013816:Thermodynamics
chemical_list: D010958:Plasminogen; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases
keywords: Streptococcus; bacterial pathogenesis; binding site mapping; cell surface receptor; crystal structure; gram-positive bacteria; host-pathogen interaction; human plasminogen; peptide array; plasminogen; pneumococcal GAPDH; protein-protein interaction