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Kinetic analysis of the leucyl/phenylalanyl-tRNA-protein transferase with acceptor peptides possessing different N-terminal penultimate residues.

ABSTRACT: The introduction of non-natural amino acids at the N-terminus of peptides/proteins using leucyl/phenylalanyl-tRNA-protein transferase (L/F-transferase) is a useful technique for protein engineering. To accelerate the chemoenzymatic reaction, here we systematically optimized the N-terminal penultimate residue of the acceptor peptide. Positively charged, small, or hydrophilic amino acids at this position show positive effects for the reaction. Kinetic analysis of peptides possessing different penultimate residues suggests that the side chain of the residue affects peptide-binding affinity towards the L/F-transferase. These findings also provide biological insight into the effect of the penultimate amino acid on substrate specificity of natural proteins to be degraded via the N-end rule pathway.

SUBMITTER: Kawaguchi J

PROVIDER: S-EPMC3722611 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Kinetic analysis of the leucyl/phenylalanyl-tRNA-protein transferase with acceptor peptides possessing different N-terminal penultimate residues.

Kawaguchi Jun J Maejima Kumino K Kuroiwa Hiroyuki H Taki Masumi M

FEBS open bio 20130611

The introduction of non-natural amino acids at the N-terminus of peptides/proteins using leucyl/phenylalanyl-tRNA-protein transferase (L/F-transferase) is a useful technique for protein engineering. To accelerate the chemoenzymatic reaction, here we systematically optimized the N-terminal penultimate residue of the acceptor peptide. Positively charged, small, or hydrophilic amino acids at this position show positive effects for the reaction. Kinetic analysis of peptides possessing different penu ...[more]

PMID: 23905007

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The crystal structure of leucyl/phenylalanyl-tRNA-protein transferase from Escherichia coli.

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