Chains and heterogens:
PDB Chain Sequences:
>1k4pA (A:) fdaipdviqafkngefvvvlddpsreneadliiaaesvtteqmafmvrhssglicapltp erttaldlpqmvthnadprgtaytvsvdaehpstttgisahdralacrmlaapdaqpshf rrpghvfplravaggvrarrghteagvelcrlagkrpvaviseivddgqevegravraap gmlrgdecvafarrwglkvctiedmiahvektegkl