Involved in the maturation of iron-sulfur (Fe-S) proteins (PubMed:27671355, PubMed:27517714). May function as a Fe-S cluster carrier (PubMed:27671355). Is required for S.aureus growth under conditions that impose a high demand for lipoic acid, likely via a role in the maturation of the lipoate synthase LipA (PubMed:27671355). Is non-essential for growth in conditions that impose a low demand for lipoic acid or Fe-S clusters, such as fermentative growth (PubMed:27671355, PubMed:27517714). Seems also to be involved in the maturation of AcnA, LeuCD and IlvD proteins, that utilize Fe-S cluster cofactors, and its role increases under conditions of high-demand for Fe-S clusters (respiratory growth) (PubMed:27517714). Is not involved in the repair of Fe-S clusters damaged by reactive oxygen species or in the physical protection of Fe-S clusters from oxidants (PubMed:27517714). Displays synergy with the Fe-S cluster carrier Nfu (PubMed:27517714). Transcription of sufT decreases when aerobically cultured cells are shifted to an anaerobic (fermentative) environment, and increases upon reaeration (PubMed:27517714). Up-regulated upon culture in serine dropout medium relative to liquid 20 AA medium (PubMed:27671355). Cells lacking this gene have decreased activities of the Fe-S cluster-dependent enzymes AcnA, LeuCD and IlvD, meaning a defect in the assembly of Fe-S proteins (PubMed:27517714). They are capable of growth in liquid chemically defined medium containing the 20 canonical amino acids (AA) and glucose as a carbon source, but display growth defects in defined medium lacking leucine and isoleucine (PubMed:27517714). In contrast, the deletion mutant strain is unable to grow upon the same 20 AA medium in solid form; supplementation of the solid 20 AA medium with lipoic acid fully corrects the growth of the mutant strain, and returning the sufT gene in trans also corrects growth in the absence of lipoic acid (PubMed:27671355). Further experimentation found that S.aureus growth upon solid chemically defined media was highly reliant upon the lipoamide-requiring enzymes pyruvate dehydrogenase (Pdh) and branched chain keto-acid dehydrogenase (Bck); the reliance upon Pdh and Bck for growth was decreased upon culture in liquid defined media (PubMed:27671355). A strain lacking SufT displays phenotypes consistent with decreased activities of multiple lipoamide-dependent enzymes (LipA, Pdh, Bck and Gcv) (PubMed:27671355). Belongs to the MIP18 family.