| Title : Peptide macrocyclization catalyzed by a prolyl oligopeptidase involved in alpha-amanitin biosynthesis - Luo_2014_Chem.Biol_21_1610 |
| Author(s) : Luo H , Hong SY , Sgambelluri RM , Angelos E , Li X , Walton JD |
| Ref : Chemical Biology , 21 :1610 , 2014 |
| Abstract : Amatoxins are ribosomally encoded and posttranslationally modified peptides that account for the majority of fatal mushroom poisonings of humans. A representative amatoxin is the bicyclic octapeptide alpha-amanitin, formed via head-to-tail macrocyclization, which is ribosomally biosynthesized as a 35-amino acid propeptide in Amanita bisporigera and in the distantly related mushroom Galerina marginata. Although members of the prolyl oligopeptidase (POP) family of serine proteases have been proposed to play a role in alpha-amanitin posttranslational processing, the exact mechanistic details are not known. Here, we show that a specific POP (GmPOPB) is required for toxin maturation in G. marginata. Recombinant GmPOPB catalyzed two nonprocessive reactions: hydrolysis at an internal Pro to release the C-terminal 25-mer from the 35-mer propeptide and transpeptidation at the second Pro to produce the cyclic octamer. On the other hand, we show that GmPOPA, the putative housekeeping POP of G. marginata, behaves like a conventional POP. |
| ESTHER : Luo_2014_Chem.Biol_21_1610 |
| PubMedSearch : Luo_2014_Chem.Biol_21_1610 |
| PubMedID: 25484237 |
Luo H, Hong SY, Sgambelluri RM, Angelos E, Li X, Walton JD (2014)
Peptide macrocyclization catalyzed by a prolyl oligopeptidase involved in alpha-amanitin biosynthesis
Chemical Biology
21 :1610
Luo H, Hong SY, Sgambelluri RM, Angelos E, Li X, Walton JD (2014)
Chemical Biology
21 :1610