radiotolerant

Edge evidence

• ionizing or UV radiation exposure challenges radiotolerant METPO:2007406

  Radiation exposure is the environmental challenge the trait counters.

  • DOI:10.3390/genes14091803 Deinococcus radiodurans is the reference organism for surviving ionizing radiation, UV, desiccation, and oxidizing agents.
• DNA repair enables radiotolerant RO:0002327

  Efficient repair of radiation-induced DNA lesions enables survival.

  • DOI:10.1101/cshperspect.a012765 Review of extreme radiation resistance highlights efficient DNA repair as a core radiotolerance mechanism.
• manganese-antioxidant proteome protection enables radiotolerant RO:0002327

  Mn-antioxidant protection of the proteome preserves repair capacity under irradiation.

  • DOI:10.1101/cshperspect.a012765 Intracellular Mn/Fe ratio correlates with bacterial radiation resistance.
• ionizing or UV radiation exposure causes reactive oxygen species (ROS) biolink:causes

  Ionizing/UV radiation produces reactive oxygen species.

  • DOI:10.1371/journal.pone.0304810 Another aftermath of irradiation is the production of reactive oxygen species (ROS); general mechanism across microbes.
• manganese(II) ion acts as antioxidant against reactive oxygen species (ROS)

  Mn2+ acts as an antioxidant that scavenges ROS.

  • DOI:10.1128/spectrum.03838-23 Manganese is an antioxidant, acting as a sponge of ROS; general bacterial mechanism.
• iron(II) ion promotes reactive oxygen species (ROS) RO:0002213

  Fe2+ furthers the spread of ROS through Fenton chemistry.

  • DOI:10.1128/spectrum.03838-23 Iron furthers the spread of ROS through Fenton chemistry; mechanistic basis of Mn/Fe ratio association with tolerance.
• manganese(II) ion part of manganese-antioxidant proteome protection biolink:part_of

  Mn2+ antioxidant activity is part of the Mn-antioxidant proteome protection process.

  • DOI:10.1128/spectrum.03838-23 Intracellular Mn/Fe ratio is the best-understood predictor of IR tolerance; Mn acts as a ROS sponge protecting the proteome.
• RecA recombinase mediates homologous recombination

  RecA mediates homologous recombination repair of double-strand breaks.

  • DOI:10.3390/su17177864 HR is central for double-strand break repair, with RecA abundant and RecA expression increasing eightfold after 15 kGy.
• homologous recombination part of DNA repair biolink:part_of

  Homologous recombination is a component of radiation-induced DNA repair.

  • DOI:10.3390/su17177864 HR is central for double-strand break repair of radiation-induced lesions.
• nucleotide excision repair (UvrABC) part of DNA repair biolink:part_of

  UvrABC nucleotide excision repair repairs UV-induced helix-distorting lesions.

  • DOI:10.3390/genes14091803 UvrA is the initial damage sensor in NER, recruiting UvrB and, with UvrC, performing dual-incision to remove UV-induced damaged DNA.
• carotenoid pigments scavenges reactive oxygen species (ROS)

  Carotenoid pigments scavenge ROS as non-enzymatic antioxidants.

  • DOI:10.3390/su17177864 The carotenoid deinoxanthin scavenges ROS quantitatively (removed up to 69.7% H2O2 and quenched singlet oxygen up to 99%).