Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 19092.72 
• Atom Count: 1276 
• Residue Count: 167 
• Unique protein chains: 1

103L

HOW AMINO-ACID INSERTIONS ARE ALLOWED IN AN ALPHA-HELIX OF T4 LYSOZYME

• DOI: 10.2210/pdb103L/pdb

• Classification: HYDROLASE(O-GLYCOSYL)
• Organism(s): Enterobacteria phage T4


• Deposited: 1992-09-29 Released: 1993-10-31 
• Deposition Author(s): Heinz, D.W., Matthews, B.W.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.9 Å

Literature

How amino-acid insertions are allowed in an alpha-helix of T4 lysozyme.

Heinz, D.W., Baase, W.A., Dahlquist, F.W., Matthews, B.W.

(1993) Nature 361: 561-564

• PubMed: 8429913 
• DOI: 10.1038/361561a0
• Primary Citation of Related Structures:  
  205L, 201L, 104L, 102L


• PubMed Abstract: 
  

Studies of extant protein sequences indicate that amino-acid insertions and deletions are preferentially located in loop regions, which has traditionally been explained as the result of selection removing deleterious mutations within secondary structural elements from the population. But there is no a priori reason to discount the possibility that insertions within secondary structure could either be tolerated until compensatory mutations arise, or have effects that are propagated away from secondary structure into loops. Earlier studies have indicated that insertions are generally tolerated, although much less well within secondary structure elements than in loop regions. Here we show that amino-acid insertions in an alpha-helix of T4 lysozyme can be accepted in two different ways. In some cases the inserted amino acids are accommodated within the helix, leading to the translocation of wild-type residues from the helix to the preceding loop. In other cases the insertion causes a 'looping-out' in the first or last turn of the helix. The individual structural responses seem to be dominated by the maintenance of the interface between the helix and the rest of the protein.

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Organizational Affiliation: 

Institute of Molecular Biology, University of Oregon, Eugene 97403.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
T4 LYSOZYME	A	167	Enterobacteria phage T4	Gene Names: E EC: 3.2.1.17
Find proteins for P00720 (Enterobacteria phage T4) Go to UniProtKB:  P00720

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
CL	A	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M
BME	A	BETA-MERCAPTOETHANOL C2 H6 O S DGVVWUTYPXICAM-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.9 Å
• Space Group: P 3₂ 2 1

Unit Cell:

Length (Å)	Angle (°)
a = 60.900	α = 90.00
b = 60.900	β = 90.00
c = 95.600	γ = 120.00

Software Package:

Software Name	Purpose
TNT	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1992-09-29 
• Released Date: 1993-10-31 
• Deposition Author(s): Heinz, D.W., Matthews, B.W.

Revision History 

• Version 1.0: 1993-10-31
  Type: Initial release
• Version 1.1: 2008-03-24
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance