Chains and heterogens:
PDB Chain Sequences:
>1bg4A (A:) easvsidakfkahgkkylgtigdqytltkntknpaiikadfgqltpensmkwdatepnrg qftfsgsdylvnfaqsngklirghtlvwhsqlpgwvssitdkntlisvlknhittvmtry kgkiyawdvlneifnedgslrnsvfynvigedyvriafetarsvdpnaklyindynldsa gyskvngmvshvkkwlaagipidgigsqthlgagagsavagalnalasagtkeiaiteld iagasstdyvnvvnaclnqakcvgitvwgvadpdswrsssspllfdgnynpkaaynaian al