claim: Ned Stark was introduced in 1996's A Storm of Swords.
evidence: In enzymology , a 4-hydroxyphenylacetaldehyde dehydrogenase is an enzyme that catalyzes the chemical reaction. enzymology. enzymology. enzyme. enzyme. catalyzes. catalysis. chemical reaction. chemical reaction. 4-hydroxyphenylacetaldehyde. 4-hydroxyphenylacetaldehyde. 4-hydroxyphenylacetaldehyde + NAD + + H2O 4-hydroxyphenylacetate + NADH + 2 H +. 4-hydroxyphenylacetaldehyde. 4-hydroxyphenylacetaldehyde. 4-hydroxyphenylacetate. 4-hydroxyphenylacetate. NADH. nicotinamide adenine dinucleotide. The 3 substrates of this enzyme are 4-hydroxyphenylacetaldehyde , NAD + , and H2O , whereas its 3 products are 4-hydroxyphenylacetate , NADH , and H + .. enzyme. enzyme. substrates. substrate ( biochemistry ). 4-hydroxyphenylacetaldehyde. 4-hydroxyphenylacetaldehyde. products. product ( chemistry ). 4-hydroxyphenylacetate. 4-hydroxyphenylacetate. NADH. nicotinamide adenine dinucleotide. This enzyme belongs to the family of oxidoreductases , specifically those acting on the aldehyde or oxo group of donor with NAD + or NADP + as acceptor .. enzyme. enzyme. The systematic name of this enzyme class is 4-hydroxyphenylacetaldehyde  : NAD + oxidoreductase .. enzyme. enzyme. 4-hydroxyphenylacetaldehyde. 4-hydroxyphenylacetaldehyde. oxidoreductase. oxidoreductase. systematic name. List of enzymes. This enzyme is also called 4-HPAL dehydrogenase .. enzyme. enzyme. This enzyme participates in tyrosine metabolism .. enzyme. enzyme. tyrosine metabolism. tyrosine metabolism