Cysteine desulfurase, of the core iron-sulfur cluster (ISC) assembly complex, that catalyzes the desulfuration of L-cysteine to L-alanine, as component of the cysteine desulfurase complex, leading to the formation of a cysteine persulfide intermediate at the active site cysteine residue and participates in the [2Fe-2S] clusters assembly on the scaffolding protein ISCU ( ). The persulfide is then transferred on the flexible Cys loop from the catalytic site of NFS1 to the surface of NFS1 . After the NFS1-linked persulfide sulfur is transferred to one of the conserved Cys residues of the scaffold, a reaction assisted by FXN (By similarity). The core iron-sulfur cluster (ISC) assembly complex is involved in the de novo synthesis of a [2Fe-2S] cluster, the first step of the mitochondrial iron-sulfur protein biogenesis. This process is initiated by the cysteine desulfurase complex (NFS1:LYRM4:NDUFAB1) that produces persulfide which is delivered on the scaffold protein ISCU in a FXN-dependent manner. Then this complex is stabilized by FDX2 which provides reducing equivalents to accomplish the [2Fe-2S] cluster assembly. Finally, the [2Fe-2S] cluster is transferred from ISCU to chaperone proteins, including HSCB, HSPA9 and GLRX5 (By similarity).
May catalyze the desulfuration of L-cysteine to L-alanine as component of the cysteine desulfurase complex (NFS1:LYRM4), leading to the formation of a cysteine persulfide intermediate (, ). Acts as a sulfur donor for MOCS3 by transferring the sulfur of the cysteine persulfide intermediate on MOCS3 (, ).
Subcellular locations: Mitochondrion
Subcellular locations: Cytoplasm, Nucleus, Cytoplasm, Cytoskeleton, Microtubule organizing center, Centrosome
Predominantly expressed in heart and skeletal muscle. Also found in brain, liver and pancreas.