Involved in the biosynthesis of a nickel-pincer cofactor ((SCS)Ni(II) pincer complex). Catalyzes the ATP-dependent incorporation of two sulfur atoms in pyridinium-3,5-biscarboxylic acid mononucleotide (P2CMN) to yield pyridinium-3,5-bisthiocarboxylic acid mononucleotide (P2TMN). The source of sulfur is the enzyme itself: Cys-176 of LarE is the sulfur donor, thereby being converted into dehydroalanine, and is not regenerated in vivo. Thus, two molecules of LarE undergo sacrificial sulfur transfer to create one P2TMN (PubMed:27114550). Binds nickel (PubMed:24710389). Is required for the activation of the lactate racemase LarA (PubMed:24710389). May also be involved in the activation of other nickel-pincer cofactor-dependent enzymes (PubMed:27114550). [LarE protein]-L-cysteine + ATP + pyridinium-3,5-dicarboxylate mononucleotide = [LarE protein]-dehydroalanine + AMP + diphosphate + H(+) + pyridinium-3-carboxylate-5-thiocarboxylate mononucleotide [LarE protein]-L-cysteine + ATP + pyridinium-3-carboxylate-5-thiocarboxylate mononucleotide = [LarE protein]-dehydroalanine + AMP + diphosphate + H(+) + pyridinium-3,5-bisthiocarboxylate mononucleotide Induced by L-lactate and repressed by D-lactate. Is thus regulated by the L-lactate/D-lactate ratio. Makes part of the lar operon (larABCDE). Deletion of this gene leads to a loss of lactate racemase activity. Belongs to the LarE family.