Merck, G0413-1VL, β(1→4)-Galactosidase, positionally specific from Streptococcus pneumoniae

β-Galactosidase is present in bacteria, fungi, yeast and animal organs. It is also found in fruits, such as apples, almonds and apricots. β-Galactosidase is a tetramer and is made up of four polypeptide chains consisting of amino acids that assemble to form five structural domains. The domains are jelly roll barrel, a central domain that serves as an active site and the remaining domains are composed of β-sandwich and fibronectin.