Involved in the breakdown of mucin-type O-linked glycans. Specifically removes the T-antigen disaccharide (Gal-beta-1,3-GalNAc-alpha) from extracellular host glycoproteins. Representative of a broadly important class of virulence factors. H2O + O(3)-[beta-D-galactosyl-(1->3)-N-acetyl-alpha-D-galactosaminyl]-L-threonyl-[protein] = beta-D-galactosyl-(1->3)-N-acetyl-D-galactosamine + L-threonyl-[protein] H2O + O(3)-[beta-D-galactosyl-(1->3)-N-acetyl-alpha-D-galactosaminyl]-L-seryl-[protein] = beta-D-galactosyl-(1->3)-N-acetyl-D-galactosamine + L-seryl-[protein] Has been shown to be localized at the cell surface. Is a multimodular protein that comprises seven distinct domains. The catalytic glycoside hydrolase domain resides in domain 3 (residues 602-893). Possesses four potential carbohydrate-binding modules (CBMs) (By similarity). Was identified as a vaccine antigen as it provides significant cross-protection in a stringent mouse model of lethal sepsis. The hydrolysis reaction catalyzed by SpGH101 proceeds with retention of the anomeric configuration. Belongs to the glycosyl hydrolase 101 family. A subfamily.