Chains and heterogens:
PDB Chain Sequences:
>4y50A (A:) stgsatttpidslddayitpvqigtpaqtlnldfdtgssdlwvfssettasevdgqtiyt psksttakllsgatwsisygdgssssgdvytdtvsvggltvtgqavesakkvsssfteds tidgllglafstlntvsptqqktffdnakasldspvftadlgyhapgtynfgfidttayt gsitytavstkqgfwewtstgyavgsgtfkstsidgiadtgttllylpatvvsaywaqvs gakssssvggyvfpcsatlpsftfgvgsarivipgdyidfgpistgssscfggiqssagi ginifgdvalkaafvvfngattptlgfask