Choline-sulphatase is involved in the synthesis of glycine betaine from choline. The symbiotic soil bacterium Rhizobium meliloti can synthesize glycine betaine from choline-O-sulphate and choline to protect itself from osmotic stress. This biosynthetic pathway is encoded by the betICBA locus, which comprises a regulatory gene, betI, and three structural genes, betC (choline sulfatase), betB (betaine aldehyde dehydrogenase), and betA (choline dehydrogenase). betICBA genes constitute a single operon.
Jiyao W et al.(2023). "The conserved domain database in 2023.",