The domain within your query sequence starts at position 31 and ends at position 373; the E-value for the 3a7u domain shown below is < 1e-12.
GLILQSISNDVYENLAFEDWIHDHIHLEGKPILFLWRNSPSVVIGRHQNPWQECNLHLMR
QEGIKLARRKSGGGAVYHDMGNINLTFFTTKTKYDRMENLKLIVRALNAVQPQLDVQPTK
KFDLLLDGQFKISGTASKIGRTAAYHHCTLLCSTNRTALSSSLKSPYCGIKSNATPSIPS
AVKNLLERDSTLTCEVLMSAVAAEYAAHHQVDGHVNLINPADETMFPGINRKVKELQSWE
WVYGRTPKFTVDTTFHVPYEQAHLEIQVFMDVKNGRIETCAIKAPDHWLPLEIGEKLNSS
FIGSKFCPVETTLLTNVLLRTCPGDHHLHSKWYILCEKIRGIM
This is a PDB domain - please see the PDBSUM entry of 3a7u for further annotation