In enzymology, a galactose-6-sulfurylase (EC 2.5.1.5) is an enzyme that catalyzes the chemical reaction

Eliminates sulfate from the D-galactose 6-sulfate residues of porphyran, producing 3,6-anhydrogalactose residues.

This enzyme belongs to the family of transferases, specifically those transferring aryl or alkyl groups other than methyl groups. The systematic name of this enzyme class is D-galactose-6-sulfate:alkyltransferase (cyclizing). Other names in common use include porphyran sulfatase, galactose-6-sulfatase, and galactose 6-sulfatase.

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• Rees DA (November 1961). "Enzymic synthesis of 3:6-anhydro-l-galactose within porphyran from l-galactose 6-sulphate units". The Biochemical Journal. 81 (2): 347–52. PMC 1243346. PMID 16748934.