Chains and heterogens:
PDB Chain Sequences:
>1f57A (A:) arstntfnyatyhtldeiydfmdllvaehpqlvsklqigrsyegrpiyvlkfstggsnrp aiwidlgihsrewitqatgvwfakkftedygqdpsftaildsmdifleivtnpdgfafth sqnrlwrktrsvtssslcvgvdanrnwdagfgkagassspcsetyhgkyansevevksiv dfvkdhgnfkaflsihsysqlllypygyttqsipdktelnqvaksavaalkslygtsyky gsiittiyqasggsidwsynqgikysftfelrdtgrygfllpasqiiptaqetwlgvlti mehtvnn