title: Bypassing the ribosome: peptide synthesis without translation.
abstract: Chemical peptide synthesis is well-established but has drawbacks, notably the need to protect side-chain functional groups during reactions. Proteolytic enzymes may be used 'in reverse' to catalyse peptide synthesis without side-chain protection and avoiding the danger of racemization. Enzymic syntheses may use either an equilibrium or a kinetic strategy. Equilibrium synthesis is simply the reversal of hydrolysis, using any type of protease. Kinetic synthesis involves time-dependent acyl transfer using activated substrates and a serine or cysteine protease. Enzymic synthesis often takes place in partially aqueous or non-aqueous reaction media; the medium can often desirably influence the protease's properties. It is possible to tailor a protease to improve its usefulness in peptide synthesis; one can alter the enzyme's properties by means such as chemical modification, PEG-coupling or protein engineering.
authors.affiliation: School of Biological Sciences, Dublin City University, Ireland.
authors.forename: A
authors.initials: A
authors.lastname: Murphy
authors.forename: C
authors.initials: C
authors.lastname: O Fágáin
mesh_terms: D001665:Binding Sites; D001671:Biochemistry / Q000379:methods*; D001709:Biotechnology / Q000379:methods; D011232:Chemical Precipitation; D010450:Endopeptidases / Q000737:chemistry* / Q000145:classification / Q000378:metabolism*; D007700:Kinetics; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry; D015202:Protein Engineering; D012997:Solvents
chemical_list: D010455:Peptides; D011134:Polysaccharides; D012997:Solvents; D011092:Polyethylene Glycols; D010450:Endopeptidases