With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Reba McEntire sang for charity.
text_B: In enzymology , a 1,4-lactonase is an enzyme that catalyzes the generic chemical reaction  :. enzymology. enzymology. enzyme. enzyme. catalyzes. catalysis. chemical reaction. chemical reaction. a 1,4-lactone + H2O a 4-hydroxyacid. 1,4-lactone. 1,4-lactone. 4-hydroxyacid. 4-hydroxyacid. Thus , the two substrates of this enzyme are 1,4-lactone and H2O , whereas its product is 4-hydroxyacid .. enzyme. enzyme. substrates. substrate ( biochemistry ). 1,4-lactone. 1,4-lactone. product. product ( chemistry ). 4-hydroxyacid. 4-hydroxyacid. This enzyme belongs to the family of hydrolases , specifically those acting on carboxylic ester bonds .. enzyme. enzyme. ester. ester. The systematic name of this enzyme class is 1,4-lactone .. enzyme. enzyme. 1,4-lactone. 1,4-lactone. systematic name. List of enzymes. This enzyme is also called gamma-lactonase .. enzyme. enzyme. This enzyme participates in galactose metabolism and ascorbate and aldarate metabolism .. enzyme. enzyme. galactose metabolism. galactose metabolism. ascorbate and aldarate metabolism. ascorbate and aldarate metabolism. It employs one cofactor , calcium .. cofactor. cofactor ( biochemistry ). calcium. calcium
not_related.