LANCL3 (LanC-like family member 3) is an X-linked gene encoding a protein involved in protein damage repair through glutathione conjugation. While initially hypothesized to participate in lanthionine biosynthesis analogous to bacterial LanC enzymes, LANCL3 does not contribute to lanthionine ketimine production in mammalian brains 1. Instead, LANCL3 functions as part of a family of LanCL proteins that catalyze the addition of glutathione to dehydroamino acids (Dha/Dhb) generated at phosphorylated sites in proteins, driving irreversible C-glutathionylation 2. This mechanism serves as an enzyme-mediated damage repair system that removes reactive electrophilic species from the proteome, particularly those arising from aberrant phosphorylation-induced protein damage 2. Physiologically, LANCL3 appears important for maintaining proteome stability, as LanCL knockout in mice can result in premature death 2. Clinically, LANCL3 has relevance to McLeod syndrome pathogenesis; deletions spanning LANCL3 through the neighboring XK gene cause multi-gene deletion syndromes characterized by neurological and hematological manifestations 3.