_EC 1.2.-.- Acting on the aldehyde or oxo group of donors. 1,276 PDB entries  
EC 1.-.-.- Oxidoreductases. [21,435 PDB entries]
EC 1.2.-.- Acting on the aldehyde or oxo group of donors. [1,276 PDB entries]
EC 1.2.1.- With NAD(+) or NADP(+) as acceptor. [958 PDB entries]
EC 1.2.2.- With a cytochrome as acceptor. [-]
EC 1.2.3.- With oxygen as acceptor. [47 PDB entries]
EC 1.2.4.- With a disulfide as acceptor. [90 PDB entries]
EC 1.2.5.- With a quinone or similar compound as acceptor. [13 PDB entries]
EC 1.2.7.- With an iron-sulfur protein as acceptor. [147 PDB entries]
EC 1.2.98.- With other, known, acceptors. [2 PDB entries]
EC 1.2.99.- With other acceptors. [19 PDB entries]

[-] signifies that there are no PDB entries for the given enzyme subclass