The secondary structure of the peripheral arm (hydrophilic domain) of complex I from T. thermophilus HB-8 with 3.3 angstrom resolution. It consists of alpha-helices, β strands, 3-10 helices, and loops. This subcomplex has Y shaped, and contains 8 hydrophilic subunits (Nqo1 to 6, Nqo9, and Nqo15) with total 10040 of residues.

PDB ID: 2FUG (PDB)