Thank you for this additional information! I had not heard of cyclic peptides. To my knowledge, no one has intentionally looked for cyclic peptides in cerebrolysin. However, I think it’s pretty unlikely. From what I read about cyclic peptides, they are either derived from natural sources (SFTI-1) or they are synthesized (as in this paper). Synthesizing cyclic peptides involves multiple steps just to get everything to fold correctly. So, it seems unlikely that the random cleavage of brain proteins that occurs in Cerebrolysin synthesis would yield any cyclic peptides.
Yes, I agree, I think it is pretty unlikely. But not completely impossible. As I said it should be pretty easy to find them if they are in the lysate via, HP liquid chromatography. Brain penetrant cyclic peptides should on the whole be significantly less polar than acyclic polypeptides of similar mass.
Thank you for this additional information! I had not heard of cyclic peptides. To my knowledge, no one has intentionally looked for cyclic peptides in cerebrolysin. However, I think it’s pretty unlikely. From what I read about cyclic peptides, they are either derived from natural sources (SFTI-1) or they are synthesized (as in this paper). Synthesizing cyclic peptides involves multiple steps just to get everything to fold correctly. So, it seems unlikely that the random cleavage of brain proteins that occurs in Cerebrolysin synthesis would yield any cyclic peptides.
Yes, I agree, I think it is pretty unlikely. But not completely impossible. As I said it should be pretty easy to find them if they are in the lysate via, HP liquid chromatography. Brain penetrant cyclic peptides should on the whole be significantly less polar than acyclic polypeptides of similar mass.