10789
By studying the interaction of different truncated or mutated A beta peptides with heme or protoporphyrin , we further found that the porphyrin ring of heme is implicated to interact preferentially with the Phe ( 19 ) residue , facilitating the binding of heme to A beta and disturbing the interstrand aromatic interaction between the Phe residues , which is crucial for A beta fibrillation .
 Chemical: heme; Chemical: protoporphyrin; Chemical: porphyrin; Chemical: heme; Chemical: Phe; Chemical: heme; Chemical: Phe
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: heme; Chemical: protoporphyrin; Chemical: porphyrin; Chemical: heme; Chemical: Phe; Chemical: heme; Chemical: Phe