Article

Role of amino acid properties to determine backbone tau(N-Calpha-C') stretching angle in peptides and proteins.

Department of Crystallography and Biophysics, University of Madras, Guindy campus, Chennai--600025, India.
Biophysical Chemistry (impact factor: 2.2). 04/2006; 120(1):24-31. DOI:10.1016/j.bpc.2005.07.012
Source: PubMed

ABSTRACT The analysis of the basic geometry of amino acid residues of protein structures has demonstrated the invariability of all the bond lengths and bond angles except for tau, the backbone N-Calpha-C' angle. This angle can be widened or contracted significantly from the tetrahedral geometry to accommodate various other strains in the structure. In order to accurately determine the cause for this deviation, a survey is made for the tau angles using the peptide structures and the ultrahigh resolution protein structures. The average deviation of N-Calpha-C' angles from tetrahedral geometry for each amino acid in all the categories were calculated and then correlated with forty-eight physiochemical, energetic and conformational properties of amino acids. Linear and multiple regression analysis were carried out between the amino acid deviation and the 48 properties. This study confirms the deviation of tau angles in both the peptide and protein structures but similar forces do not influence them. The peptide structures are influenced by physical properties whereas as expected the conformational properties influence the protein structures. And it is not any single property that dominates the deviation but the combination of different factors contributes to the tau angle deviation.

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    Alice Qinhua Zhou, Corey S O'Hern, Lynne Regan
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    Protein Science 07/2011; 20(7):1166-71. · 2.80 Impact Factor
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Keywords

amino acid
 
amino acid deviation
 
amino acid residues
 
amino acids
 
average deviation
 
backbone N-Calpha-C' angle
 
bond angles
 
bond lengths
 
conformational properties
 
conformational properties influence
 
different factors contributes
 
multiple regression analysis
 
N-Calpha-C' angles
 
peptide structures
 
protein structures
 
similar forces
 
single property
 
tau angle deviation
 
tau angles
 
ultrahigh resolution protein structures
 

S M Malathy Sony