>1tu4B (B:) observed residues (from ATOM records)
icqfklvllgesavgksslvlrfvkgqfqestigaafltqtvclddttvkfeiwdtagqe
ryhslapmyyrgaqaaivvyditneesfaraknwvkelqrqaspnivialsgnkadlank
ravdfqeaqsyaddnsllfmetsaktsmnvneifmaiakklp