facultative oxygen preference

Edge evidence

• facultative oxygen preference responds to molecular oxygen

  Facultative oxygen preference depends on coping with oxygen changes.

  • DOI:10.1111/cmi.13338 cope with changing oxygen levels Supports oxygen flexibility as the trait-level mechanism.
• molecular oxygen enables aerobic respiration RO:0002327

  Oxygen availability permits aerobic respiratory growth.

  • DOI:10.1016/j.celrep.2023.112444 transfer electrons from the ETC to O2 Supports oxygen use by terminal oxidases during respiration.
• facultative oxygen preference has alternative process anaerobic respiration or fermentation

  Growth without oxygen can use alternative electron acceptors or fermentation.

  • DOI:10.1089/ars.2011.4051 utilizing other substrates as final electron acceptors Supports oxygen-independent respiratory alternatives under oxygen shortage.
• oxygen-sensing regulation controls adaptation to molecular oxygen

  Oxygen-sensing regulators mediate metabolic adaptation across oxygen regimes.

  • DOI:10.1089/ars.2011.4051 Fnr-type transcriptional regulators that directly sense O2 Supports regulatory oxygen sensing as a causal graph entity.
• oxygen-sensing regulation represses aerobic energy-generating pathways

  Oxygen-responsive regulators (FNR/ArcA) repress aerobic energy-generating pathways under anaerobiosis.

  • DOI:10.1128/aem.01491-23 FNR and ArcA "repress aerobic energy-generating pathways" under anaerobiosis.
• oxygen-sensing regulation induces anaerobic metabolism genes

  Oxygen-responsive regulators induce anaerobic metabolism genes enabling growth without O2.

  • DOI:10.1128/aem.01491-23 FNR and ArcA "induce genes for anaerobic metabolism"; general regulatory edge for facultative bacteria.
• nitrate promotes anaerobic respiration or fermentation RO:0002213

  Nitrate substitutes for O2 as terminal electron acceptor, supporting non-fermentative anaerobic respiration.

  • DOI:10.1128/msphere.00774-23 "addition of nitrate as a TEA promotes anaerobic respiration"; broadly relevant across facultative species with nitrate reductases.
• molecular oxygen enables cytochrome bd terminal oxidase RO:0002327

  Trace/available oxygen lets cells use cytochrome bd as terminal oxidase; active terminal enzyme depends on which final electron acceptor (oxygen vs fumarate) is available.

  • DOI:10.1128/jb.00389-22 "which of these terminal enzymes is active in electron transfer depends on the availability of the final electron acceptor: fumarate or oxygen"; supports electron-acceptor-dependent branch switching.