Exploring host-pathogen interactions through genome wide protein microarray analysis

Abstract

During bacterial pathogenesis extensive contacts between the human and the bacterial extracellular proteomes take place. The identification of novel host-pathogen interactions by standard methods using a case-by-case approach is laborious and time consuming. To overcome this limitation, we took advantage of large libraries of human and bacterial recombinant proteins. We applied a large-scale protein microarray-based screening on two important human pathogens using two different approaches: (I) 75 human extracellular proteins were tested on 159 spotted Staphylococcus aureus recombinant proteins and (II) Neisseria meningitidis adhesin (NadA), an important vaccine component against serogroup B meningococcus, was screened against ≈2300 spotted human recombinant proteins. The approach presented here allowed the identification of the interaction between the S. aureus immune evasion protein FLIPr (formyl-peptide receptor like-1 inhibitory protein) and the human complement component C1q, key players of the offense-defense fighting; and of the interaction between meningococcal NadA and human LOX-1 (low-density oxidized lipoprotein receptor), an endothelial receptor. The novel interactions between bacterial and human extracellular proteins here presented might provide a better understanding of the molecular events underlying S. aureus and N. meningitidis pathogenesis.

NadA3 Structures Reveal Undecad Coiled Coils and LOX1 Binding Regions Competed by Meningococcus B Vaccine-Elicited Human Antibodies

“…The full-length ectodomain of NadA3 is predicted to be highly extended and somewhat flexible, characteristics that may underlie previous crystallization failures ( 30 ). To increase NadA3 crystallization likelihood, we focused on N-terminal fragments that are shorter but still harbor functional and immunogenic regions ( 22 , 23 , 28 , 30 , 32 ). Hence, we sought a trimeric N-terminal fragment with minimal length and maximal stability by screening a panel of seven new NadA3 constructs which all started with residue A24 and extended variously from a maximum of residue A181 to a minimum of residue V89 ( Fig.…”

“…The NadA3 head region was previously implicated in binding the human endothelial cell receptor LOX-1 ( 28 ). To identify NadA residues mediating this interaction, we generated several NadA mutants and examined their binding to LOX-1.…”

“…Similarly, recombinant NadA was reported to stimulate human monocytes by binding Hsp90 ( 26 , 27 ). It was recently demonstrated that the NadA3 N-terminal region binds specifically to the endothelial cell receptor LOX-1 (low-density oxidized lipoprotein lectin-like receptor 1) ( 28 ). The multiple interactions of NadA with a variety of host cells and receptors are likely to enable multiple host recognition mechanisms, each potentially contributing to meningococcal pathogenicity.…”

Elucidation of host–pathogen protein–protein interactions to uncover mechanisms of host cell rewiring

“…Regrettably, their lack of solubility and their necessity of remaining in lipid-rich environment highly impairs their interactome mapping via conventional methods such as AP-MS. To overcome these challenges, Glick Y et al introduced a screening method for HP interactions, adequate for transmembrane proteins [62] named the human Membrane Protein Array (MPA). Similarly, several studies have developed and applied Protein Micro Array technologies [63] including Nucleic Acid Programmable [64] or AVEXIS (AVidity-based Extracellular Interaction Screen) [65,66] to study soluble and transmembrane HP interactions (see supplementary table 1). …”

From Immunologically Archaic to Neoteric Glycovaccines

“…A pure protein vaccine against S. aureus is not available despite a multitude of studies [68,78,79,80]. Probably, the combination of infection proteomics [81] with PS biosynthesis will lead to successful staphylococcal vaccines. In line with this hypothesis, infection of the mouse gastrointestinal tract by S. aureus necessitates the presence of both intact teichoic acid, the capsular PS, and surface proteins [82].…”