5LO4

Engineering protein stability with atomic precision in a monomeric miniprotein

Summary for 5LO4

• Entry DOI: 10.2210/pdb5lo4/pdb
• NMR Information: BMRB: 34033
• Descriptor: PPa-CH3 (1 entity in total)
• Functional Keywords: designed miniprotein ch-pi interactions weak non-covalent interactions in protiens solution structure proline-tyrosine interactions, structural protein
• Biological source: Streptococcus mutans
• Total number of polymer chains: 1
• Total formula weight: 3801.37

Authors

Baker, E.G.,Williams, C.,Hudson, K.L.,Bartlett, G.G.,Heal, J.W.,Sessions, R.B.,Crump, M.P.,Woolfson, D.N. (deposition date: 2016-08-08, release date: 2017-05-17, Last modification date: 2024-11-06)

Primary citation

Baker, E.G.,Williams, C.,Hudson, K.L.,Bartlett, G.J.,Heal, J.W.,Porter Goff, K.L.,Sessions, R.B.,Crump, M.P.,Woolfson, D.N.
Engineering protein stability with atomic precision in a monomeric miniprotein.
Nat. Chem. Biol., 13:764-770, 2017

PubMed Abstract: Miniproteins simplify the protein-folding problem, allowing the dissection of forces that stabilize protein structures. Here we describe PPα-Tyr, a designed peptide comprising an α-helix buttressed by a polyproline II helix. PPα-Tyr is water soluble and monomeric, and it unfolds cooperatively with a midpoint unfolding temperature (T) of 39 °C. NMR structures of PPα-Tyr reveal proline residues docked between tyrosine side chains, as designed. The stability of PPα is sensitive to modifications in the aromatic residues: replacing tyrosine with phenylalanine, i.e., changing three solvent-exposed hydroxyl groups to protons, reduces the T to 20 °C. We attribute this result to the loss of CH-π interactions between the aromatic and proline rings, which we probe by substituting the aromatic residues with nonproteinogenic side chains. In analyses of natural protein structures, we find a preference for proline-tyrosine interactions over other proline-containing pairs, and observe abundant CH-π interactions in biologically important complexes between proline-rich ligands and SH3 and similar domains.

PubMed: 28530710
DOI: 10.1038/nchembio.2380

Experimental method

SOLUTION NMR