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Investigation of the Effect of Turn Residues on Tetrapeptide Aldol Catalysts with β-Turn Propensity.

ABSTRACT: Peptide catalysts for a wide diversity of reaction types contain a common motif-residues that bias the sequence toward β-turn secondary structure. In this work, we explore what role that secondary structure plays in the catalysis of aldol reactions for primary amine tetrapeptide aldol catalysts. Using a lead tetrapeptide β-turn catalytic sequence, we varied the i + 1 and i + 2 residues to amino acids that would affect the β-turn propensity. We then studied the correlation between secondary structure, aldol rate enhancement, and stereoselectivity of the reaction between hydroxyacetone and 4-nitrobenzaldehyde. Using the i + 3 amide chemical shift as a measure of β-turn character, we found a rough correlation between the peptide structure and reaction kinetics but minimal effect on stereoselectivity. These trends may help aid the design of future catalytic sequences.

SUBMITTER: Liu AY

PROVIDER: S-EPMC9753199 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Investigation of the Effect of Turn Residues on Tetrapeptide Aldol Catalysts with β-Turn Propensity.

Liu Albert Y AY Calicdan Xavier A XA Glover Gene N GN Luo Xue X Barroso Gage T GT Hoppe Brooke K BK Boyle Kelsey M KM Witus Leah S LS

ACS omega 20221201 49

Peptide catalysts for a wide diversity of reaction types contain a common motif-residues that bias the sequence toward β-turn secondary structure. In this work, we explore what role that secondary structure plays in the catalysis of aldol reactions for primary amine tetrapeptide aldol catalysts. Using a lead tetrapeptide β-turn catalytic sequence, we varied the <i>i</i> + 1 and <i>i</i> + 2 residues to amino acids that would affect the β-turn propensity. We then studied the correlation between s ...[more]

PMID: 36530262

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