Sulfotransferase that utilizes 3′-phospho-5′-adenylyl sulfate (PAPS) as sulfonate donor to catalyze the transfer of sulfate to position 6 of the N-acetylgalactosamine (GalNAc) residue of chondroitin (PubMed:15215498, PubMed:9714738, PubMed:9883891). Chondroitin sulfate constitutes the predominant proteoglycan present in cartilage and is distributed on the surfaces of many cells and extracellular matrices (PubMed:9714738). Catalyzes with a lower efficiency the sulfation of Gal residues of keratan sulfate, another glycosaminoglycan (PubMed:9714738). Can also catalyze the sulfation of the Gal residues in sialyl N-acetyllactosamine (sialyl LacNAc) oligosaccharides (By similarity). May play a role in the maintenance of naive T-lymphocytes in the spleen (By similarity).
