1STB

ACCOMMODATION OF INSERTION MUTATIONS ON THE SURFACE AND IN THE INTERIOR OF STAPHYLOCOCCAL NUCLEASE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Work: 0.196 
  • R-Value Observed: 0.196 

wwPDB Validation   3D Report Full Report


This is version 1.6 of the entry. See complete history


Literature

Accommodation of insertion mutations on the surface and in the interior of staphylococcal nuclease.

Keefe, L.J.Quirk, S.Gittis, A.Sondek, J.Lattman, E.E.

(1994) Protein Sci 3: 391-401

  • DOI: https://doi.org/10.1002/pro.5560030303
  • Primary Citation of Related Structures:  
    1STA, 1STB

  • PubMed Abstract: 

    Alignment of homologous amino acid sequences reveals that insertion mutations are fairly common in evolution. Hitherto, the structural consequences of insertion mutations on the surface and in the interior of proteins of known structures have received little attention. We report here the high-resolution X-ray crystal structures of 2 site-directed insertion mutants of staphylococcal nuclease. The structure of the first insertion mutant, in which 2 glycine residues were inserted on the protein surface in the amino-terminal beta-strand, has been solved to 1.70 A resolution and refined to a crystallographic R value of 0.182. The inserted residues are accommodated in a special 3-residue beta-bulge. A bridging water molecule in the newly created cavity satisfies the hydrogen bonding requirements of the beta-sheet by forming a bifurcated hydrogen bond to 1 beta-strand, and a single hydrogen bond to the other beta-strand. The second insertion mutant contains a single leucine residue inserted at the end of the third beta-strand. The structure was solved to 2.0 A resolution and refined to a final R value of 0.196. The insertion is accommodated in a register shift that changes the conformation of the flexible loop portion of the molecule, relaxing and widening the omega turn. This structural alteration results in changes in position and coordination of a bound calcium ion important for catalysis. These structures illustrate important differences in how amino acid insertions are accommodated: as localized bulges, and as extensive register shifts.


  • Organizational Affiliation

    Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland 21205.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
STAPHYLOCOCCAL NUCLEASE150Staphylococcus aureusMutation(s): 0 
EC: 3.1.31.1
UniProt
Find proteins for P00644 (Staphylococcus aureus)
Explore P00644 
Go to UniProtKB:  P00644
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00644
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
THP
Query on THP

Download Ideal Coordinates CCD File 
C [auth A]THYMIDINE-3',5'-DIPHOSPHATE
C10 H16 N2 O11 P2
CSNCBOPUCJOHLS-XLPZGREQSA-N
CA
Query on CA

Download Ideal Coordinates CCD File 
B [auth A]CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Work: 0.196 
  • R-Value Observed: 0.196 
  • Space Group: P 41
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 47.16α = 90
b = 47.16β = 90
c = 63.15γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
PROLSQrefinement
X-PLORrefinement
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1994-07-31
    Type: Initial release
  • Version 1.1: 2008-03-03
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2017-11-29
    Changes: Derived calculations, Other
  • Version 1.4: 2019-07-17
    Changes: Data collection, Refinement description
  • Version 1.5: 2019-08-14
    Changes: Data collection, Refinement description
  • Version 1.6: 2024-02-14
    Changes: Data collection, Database references, Derived calculations