The SH in "C. necator" are unique for other organisms because it is oxygen tolerant. The active site of the SH has been studied to learn why this protein is tolerant to oxygen. A recent study showed that oxygen tolerance as implemented in the SH is based on a continuous catalytically driven detoxification of O2 missing.  The genes encoding this SH can be up-regulated under heterotrophic growth condition using glycerol in the growth media and this enables aerobic production and purification of the same enzyme.