Chains and heterogens:
PDB Chain Sequences:
>4er1E (E:) stgsatttpidslddayitpvqigtpaqtlnldfdtgssdlwvfssettasevdgqtiyt psksttakllsgatwsisygdgssssgdvytdtvsvggltvtgqavesakkvsssfteds tidgllglafstlntvsptqqktffdnakasldspvftadlgyhapgtynfgfidttayt gsitytavstkqgfwewtstgyavgsgtfkstsidgiadtgttllylpatvvsaywaqvs gakssssvggyvfpcsatlpsftfgvgsarivipgdyidfgpistgssscfggiqssagi ginifgdvalkaafvvfngattptlgfask