Members of this protein family are the DndC protein from the dnd (degradation during electrophoresis) operon. The dnd phenotype reflects a sulfur-containing modification to DNA. This operon is sparsely and sporadically distributed among bactera; among the first eight examples are members from the Actinobacteria, Firmicutes, Gammaproteobacteria, Cyanobacteria. DndC is suggested to be a sulfurtransferase. [DNA metabolism, Restriction/modification]