Cargando…

Asparagine Peptide Lyases: A SEVENTH CATALYTIC TYPE OF PROTEOLYTIC ENZYMES

The terms “proteolytic enzyme” and “peptidase” have been treated as synonymous, and all proteolytic enzymes have been considered to be hydrolases (EC 3.4). However, the recent discovery of proteins that cleave themselves at asparagine residues indicates that not all peptide bond cleavage occurs by h...

Descripción completa

Detalles Bibliográficos
Autores principales: Rawlings, Neil David, Barrett, Alan John, Bateman, Alex
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Society for Biochemistry and Molecular Biology 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3207474/
https://www.ncbi.nlm.nih.gov/pubmed/21832066
http://dx.doi.org/10.1074/jbc.M111.260026
Descripción
Sumario:The terms “proteolytic enzyme” and “peptidase” have been treated as synonymous, and all proteolytic enzymes have been considered to be hydrolases (EC 3.4). However, the recent discovery of proteins that cleave themselves at asparagine residues indicates that not all peptide bond cleavage occurs by hydrolysis. These self-cleaving proteins include the Tsh protein precursor of Escherichia coli, in which the large C-terminal propeptide acts as an autotransporter; certain viral coat proteins; and proteins containing inteins. Proteolysis is the action of an amidine lyase (EC 4.3.2). These proteolytic enzymes are also the first in which the nucleophile is an asparagine, defining the seventh proteolytic catalytic type and the first to be discovered since 2004. We have assembled ten families based on sequence similarity in which cleavage is thought to be catalyzed by an asparagine.