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H2O2 resistance and GSNO sensitivity were distinct in this study.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Threonine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-threonine","display_name":"L-Threonine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Chemical modification of the enzyme can disrupt loading and proofreading.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Nitrosative stress inhibits aminoacylation and editing activities of mitochondrial threonyl-tRNA synthetase by S-nitrosation. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32484546/ · DOI 10.1093/nar/gkaa471","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"825827c0-f4cd-5cdb-8690-e543621221fb","evidence_kind":"source_excerpt","locator":"Lines 90-96","start_line":90,"end_line":96,"excerpt":"## l-threonine-tars2-nitrosation\nChemical modification of the enzyme can disrupt loading and proofreading.\nGSNO treatment S-nitrosated human mitochondrial ThrRS and reduced both aminoacylation and editing activity in vitro.\nModel: Purified human enzyme; four modified cysteine residues; corroborating S-nitrosation detection in human cells and mouse tissues.\nLimitations: GSNO is not reduced glutathione; this exposure does not predict effects of oral glutathione. H2O2 resistance and GSNO sensitivity were distinct in this study.\nEvidence access: Primary abstract\nNitrosative stress inhibits aminoacylation and editing activities of mitochondrial threonyl-tRNA synthetase by S-nitrosation. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32484546/ · DOI 10.1093/nar/gkaa471","model_system":"Purified human enzyme; four modified cysteine residues; corroborating S-nitrosation detection in human cells and mouse tissues.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"35396730-235a-537e-8a05-c6ef2960c509","stable_key":"import-97957230-601f-5dec-8524-0812be8fadbf","title":"L-Threonine: translation, intestinal barrier, metabolism and cross-nutrient mechanisms (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary references, access levels and experimental limitations individually identified. 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