PDBsum entry 1cu2

Hydrolase

PDB id: 1cu2

Contents

Protein chain

162 a.a. *

Ligands

HED

Metals

_CL ×2

Waters ×128

* Residue conservation analysis

PDB id:

1cu2

Name:

Hydrolase

Title:

T4 lysozyme mutant l84m

Structure:

Lysozyme. Chain: a. Engineered: yes. Mutation: yes

Source:

Enterobacteria phage t4. Organism_taxid: 10665. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Dimer (from PQS)

Resolution:

1.85Å R-factor: 0.155

Authors:

N.C.Gassner,W.A.Baase,J.D.Lindstrom,J.Lu,B.W.Matthews

Key ref:

N.C.Gassner et al. (1999). Methionine and alanine substitutions show that the formation of wild-type-like structure in the carboxy-terminal domain of T4 lysozyme is a rate-limiting step in folding. Biochemistry, 38, 14451-14460. PubMed id: 10545167 DOI: 10.1021/bi9915519

Date:

20-Aug-99 Release date: 10-Nov-99

Protein chain

P00720  (ENLYS_BPT4) -  Endolysin from Enterobacteria phage T4

Seq: 164 a.a.

Struc: 162 a.a.*

* PDB and UniProt seqs differ at 5 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.3.2.1.17 - lysozyme.
• Reaction: Hydrolysis of the 1,4-beta-linkages between N-acetyl-D-glucosamine and N-acetylmuramic acid in peptidoglycan heteropolymers of the prokaryotes cell walls.

DOI no: 10.1021/bi9915519

Biochemistry 38:14451-14460 (1999)

PubMed id: 10545167

Methionine and alanine substitutions show that the formation of wild-type-like structure in the carboxy-terminal domain of T4 lysozyme is a rate-limiting step in folding.

N.C.Gassner, W.A.Baase, J.D.Lindstrom, J.Lu, F.W.Dahlquist, B.W.Matthews.

ABSTRACT

In an attempt to identify a systematic relation between the structure of a protein and its folding kinetics, the rate of folding was determined for 20 mutants of T4 lysozyme in which a bulky, buried, nonpolar wild-type residue (Leu, Ile, Phe, Val, or Met) was substituted with alanine. Methionine, which approximated the size of the original side chain but which is of different shape and flexibility, was also substituted at most of the same sites. Mutations that substantially destabilize the protein and are located in the carboxy-terminal domain generally slow the rate of folding. Destabilizing mutations in the amino-terminal domain, however, have little effect on the rate of folding. Mutations that have little effect on stability tend to have little effect on the rate, no matter where they are located. These results suggest that, at the rate-limiting step, elements of structure in the C-terminal domain are formed and have a structure similar to that of the fully folded protein. Consistent with this, two variants that somewhat increase the rate of folding (Phe104 --> Met and Val149 --> Met) are located within the carboxy-terminal domain and maintain or improve packing with very little perturbation of the wild-type structure.