| Topic | Key point | Quantitative/statistical detail | Source (author/year) | URL |
|---|---|---|---|---|
| Gene-specific evidence status | No retrieved paper explicitly mentioned UniProt **A0A1D1USM4** or gene **RvY_01767-1/RvY_01767.1**; functional annotation therefore should rely on the provided UniProt identity plus Fe/Mn-SOD family inference, not on a different similarly named gene. (pqac-00000000, pqac-00000001, pqac-00000004) | Direct literature hits for this exact gene/protein in retrieved corpus: **0** | Sadowska-Bartosz & Bartosz 2024; Sim & Inoue 2023 | https://doi.org/10.3390/ijms25158393 ; https://doi.org/10.1107/S2053230X2300523X |
| Organism context: R. varieornatus SOD repertoire | Ramazzottius varieornatus has an expanded antioxidant repertoire, including a large SOD family; this supports the biological plausibility of an Fe/Mn SOD in this species even though this exact paralog lacks direct literature. (pqac-00000008, pqac-00000009) | Reported SOD count in **R. varieornatus = 16–17 genes**; most metazoans have **<10**, humans **3** | Sadowska-Bartosz & Bartosz 2024; Hashimoto et al. 2016 | https://doi.org/10.3390/ijms25158393 ; https://doi.org/10.1038/ncomms12808 |
| Tardigrade stress-biology interpretation | Recent expert synthesis argues antioxidant systems are central to tardigrade resistance; SOD expansion is interpreted as part of ROS control during desiccation/UV stress, though duplications alone do not explain all extremotolerance. (pqac-00000013, pqac-00000014, pqac-00000017) | Eutardigrades reported with **12–16 putative SOD genes** vs heterotardigrade example with **~7**; table values included **R. varieornatus 17** | Sadowska-Bartosz & Bartosz 2024 | https://doi.org/10.3390/ijms25158393 |
| Canonical Fe/Mn SOD reaction | Fe/Mn SODs (EC 1.15.1.1) catalyze disproportionation of superoxide, the core function that should be assigned to A0A1D1USM4 unless contradicted by future gene-specific data. (pqac-00000020, pqac-00000021, pqac-00000024) | Reaction: **2 O2•− + 2 H+ → H2O2 + O2** | Zheng et al. 2023; Mishra et al. 2023 | https://doi.org/10.3390/antiox12091675 ; https://doi.org/10.3389/fpls.2023.1110622 |
| Canonical Fe/Mn SOD metal center | Mn- and Fe-SODs share closely related active-site chemistry; metal is typically coordinated by **3 His + 1 Asp + water/hydroxide**, consistent with Fe/Mn_SOD family/domain annotation in UniProt. (pqac-00000021) | Active-site coordination: **3 histidines, 1 aspartate, 1 water/hydroxide ligand** | Zheng et al. 2023 | https://doi.org/10.3390/antiox12091675 |
| Canonical localization for eukaryotic Fe/Mn SODs | In eukaryotes, Mn-SOD is typically mitochondrial and often synthesized with an N-terminal targeting peptide; Fe-SODs are mainly chloroplastic in photosynthetic taxa, so a tardigrade Fe/Mn family protein is more plausibly **mitochondrial Mn-SOD-like** than chloroplastic. (pqac-00000020, pqac-00000023) | Mitochondrial targeting/transport peptide reported up to **~24 aa** for eukaryotic SOD2 precursors | Zheng et al. 2023; Lyall et al. 2020 | https://doi.org/10.3390/antiox12091675 ; https://doi.org/10.3390/ijms21239131 |
| Recent tardigrade SOD structural context | The best direct 2023 structural study in R. varieornatus concerns **RvSOD15**, a **Cu/Zn SOD**, not A0A1D1USM4; it shows that some tardigrade SOD paralogs are atypical and may have diverged from canonical activity. This is important context but should not be conflated with the Fe/Mn target. (pqac-00000001, pqac-00000005, pqac-00000018) | RvSOD15 carries an unusual **Val87** substitution at a normally catalytic Cu ligand position; structural study resolved Cu/Zn-bound architecture | Sim & Inoue 2023 | https://doi.org/10.1107/S2053230X2300523X |
| 2024 application statistic: IVF trial | A Bacillus-derived oral SOD product (GF101) showed non-inferior IVF outcomes versus CoQ10 in a randomized trial, illustrating contemporary real-world SOD implementation beyond basic research. (pqac-00000034) | **n=86 enrolled**, **65 completed**; risk differences: clinical pregnancy **−6.27%** (95% CI −30.77 to 18.22), live birth **−1.18%** (95% CI −25.28 to 22.93), miscarriage **−13.49%** (95% CI −41.14 to 14.15) | Shin et al. 2024 | https://doi.org/10.3390/antiox13030321 |
| Application statistic: topical UVB protection | Protein transduction/topical delivery can make SOD biologically useful in skin protection. (pqac-00000026) | Topical **TAT-SOD** increased minimum erythema dose by **36.6 ± 18.4%** and reduced apoptotic sunburn cells by **47.6 ± 8.6%** | Zheng et al. 2023 | https://doi.org/10.3390/antiox12091675 |
| Application statistic: probiotic/food SOD | SOD has measurable food-biotech implementation, including fermentation-based production and functional food enrichment. (pqac-00000033) | Lactobacillus plantarum SOD production **2476.21 ± 1.52 U g−1**; fermented yogurt reached **19.827 ± 0.323 U mL−1**, **63.01–146.79%** above commercial yogurts | Zheng et al. 2023 | https://doi.org/10.3390/antiox12091675 |


*Table: This table compiles the core evidence needed to functionally annotate Ramazzottius varieornatus RvY_01767-1 / UniProt A0A1D1USM4. It distinguishes direct evidence from inference, summarizes tardigrade SOD context, and includes recent quantitative application examples relevant to SOD biology.*