These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Tautomeric state of alpha-sarcin histidines. Ndelta tautomers are a common feature in the active site of extracellular microbial ribonucleases.
    Author: Pérez-Cañadilllas JM, García-Mayoral MF, Laurents DV, Martínez del Pozo A, Gavilanes JG, Rico M, Bruix M.
    Journal: FEBS Lett; 2003 Jan 16; 534(1-3):197-201. PubMed ID: 12527386.
    Abstract:
    Extracellular fungal RNases, including ribotoxins such as alpha-sarcin, constitute a family of structurally related proteins represented by RNase T1. The tautomeric preferences of the alpha-sarcin imidazole side chains have been determined by nuclear magnetic resonance and electrostatic calculations. Histidine residues at the active site, H50 and H137, adopt the Ndelta tautomer, which is less common in short peptides, as has been found for RNase T1. Comparison with tautomers predicted from crystal structures of other ribonucleases suggests that two active site histidine residues with the Ndelta tautomer are a conserved feature of microbial ribonucleases and that this is related to their ribonucleolytic function.
    [Abstract] [Full Text] [Related] [New Search]