opportunistic pathogen

Edge evidence

• compromised host defense causes opportunistic infection biolink:causes

  Breached or weakened host defenses enable a normally innocuous microbe to cause disease.

  • DOI:10.1016/j.tim.2012.04.005 Brown et al. support context-dependent virulence in opportunistic pathogens.
• opportunistic infection enables opportunistic pathogen RO:0002327

  Context-dependent infection realizes the opportunistic-pathogen lifestyle.

  • DOI:10.1038/s41579-021-00550-7 Drew et al. support facultative shifts toward pathogenicity along the parasite-mutualist continuum.
• epithelial barrier breach / sterile site access enables opportunistic infection RO:0002327

  Barrier breach exposes sterile tissue, enabling infection by normally innocuous microbes.

  • DOI:10.1038/s41579-024-01035-z Uberoi et al.: barrier breach exposes sterile tissue to microbes (generalizable ecological/clinical edge).
• antibiotic exposure promotes microbiota dysbiosis RO:0002213

  Antimicrobial exposure disrupts the resident microbiota, producing dysbiosis.

  • DOI:10.1007/s40588-023-00190-w Jacobsen: antibiotic exposure is a common risk factor driving overgrowth of opportunists; curated as exposure to dysbiosis.
• microbiota dysbiosis increases opportunist colonization / overgrowth RO:0002213

  Dysbiosis increases colonization/overgrowth by opportunistic microbes.

  • DOI:10.1007/s40588-023-00190-w Jacobsen: defects/dysbiosis permit expansion of normally controlled opportunists (high-level ecological edge).
• opportunist colonization / overgrowth enables opportunistic infection RO:0002327

  Expanded opportunist colonization provides the population reservoir from which infection can arise.

  • DOI:10.1007/s40588-023-00190-w Jacobsen: colonization is a risk factor preceding opportunistic disease.
• host colonization without disease progresses to under host susceptibility opportunistic infection

  Most colonization is benign; only some progresses to infection under permissive host conditions, capturing context-dependence.

  • DOI:10.1038/s41579-024-01035-z Uberoi: nearly all wounds are colonized but only some progress to infection; opportunism is context-dependent, not equivalent to colonization.
• nutritional immunity / iron limitation promotes high-affinity iron acquisition RO:0002213

  Host iron limitation induces high-affinity iron transport and siderophore production, a general opportunist adaptation in-host.

  • DOI:10.1111/1751-7915.14241 Sanchez-Jimenez: under iron limitation, high-affinity iron transport systems are promoted (general iron-acquisition biology).
• high-affinity iron acquisition contributes to opportunistic infection RO:0002326

  Iron acquisition under host-imposed restriction supports opportunist fitness during infection.

  • DOI:10.1111/1751-7915.14241 Sanchez-Jimenez: iron homeostasis is an exploitable in-host fitness/virulence determinant of opportunists.