>4ibtB (B:) observed residues (from ATOM records)
ssvpsqktyqgsygfrlgflhsgtaksvtctyspalnkmfcqlaktcpvqlwvdstpppg
trvramaiykqsqhmtevvrrcphhercsdsdglappqhlirvegnlrveylddrntfrh
svvvpyeppevgsdcttihynymcnsscmggmnrrpiltiitledssgnllgrnsfevhv
cacpgrdrrreeenl