Chains and heterogens:
PDB Chain Sequences:
>1fmgA (A:) ivggytcaansipyqvslnsgshfcggslinsqwvvsaahcyksriqvrlgehnidvleg neqfinaakiithpnfngntldndimliklsspatlnsrvatvslprscaaagteclisg wgntkssgssypsllqclkapvlsnssckssypgqitgnmicvgflqggkdscqgdsggp vvcngqlqgivswgygcaqknkpgvytkvcnyvnwiqqtiaan