1L25

REPLACEMENTS OF PRO86 IN PHAGE T4 LYSOZYME EXTEND AN ALPHA-HELIX BUT DO NOT ALTER PROTEIN STABILITY

Summary for 1L25

• Entry DOI: 10.2210/pdb1l25/pdb
• Related: 1L01 1L02 1L03 1L04 1L05 1L06 1L07 1L08 1L09 1L10 1L11 1L12 1L13 1L14 1L15 1L16 1L17 1L18 1L19 1L20 1L21 1L22 1L23 1L24 1L26 1L27 1L28 1L29 1L30 1L31 1L32 1L33 1L34 1L35 1L36 2LZM
• Descriptor: T4 LYSOZYME (2 entities in total)
• Functional Keywords: hydrolase (o-glycosyl)
• Biological source: Enterobacteria phage T4
• Cellular location: Host cytoplasm : P00720
• Total number of polymer chains: 1
• Total formula weight: 18636.43

Authors

Bell, J.A.,Dao-Pin, S.,Matthews, B.W. (deposition date: 1989-05-01, release date: 1990-01-15, Last modification date: 2024-05-22)

Primary citation

Alber, T.,Bell, J.A.,Sun, D.P.,Nicholson, H.,Wozniak, J.A.,Cook, S.,Matthews, B.W.
Replacements of Pro86 in phage T4 lysozyme extend an alpha-helix but do not alter protein stability.
Science, 239:631-635, 1988

PubMed Abstract: To investigate the relation between protein stability and the predicted stabilities of individual secondary structural elements, residue Pro86 in an alpha-helix in phage T4 lysozyme was replaced by ten different amino acids. The x-ray crystal structures of seven of the mutant lysozymes were determined at high resolution. In each case, replacement of the proline resulted in the formation of an extended alpha-helix. This involves a large conformational change in residues 81 to 83 and smaller shifts that extend 20 angstroms across the protein surface. Unexpectedly, all ten amino acid substitutions marginally reduce protein thermostability. This insensitivity of stability to the amino acid at position 86 is not simply explained by statistical and thermodynamic criteria for helical propensity. The observed conformational changes illustrate a general mechanism by which proteins can tolerate mutations.

PubMed: 3277275

Experimental method

X-RAY DIFFRACTION (1.8 Å)