Document Detail


The enzyme activity allosteric regulation model based on the composite nature of catalytic and regulatory sites concept.
MedLine Citation:
PMID:  10217459     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
A new kinetic model of enzymatic catalysis is proposed, which postulates that enzyme solutions are equilibrium systems of oligomers differing in the number of subunits and in the mode of their assembly. It is suggested that the catalytic and regulatory sites of allosteric enzymes are of composite nature and appear as a result of subunits joining. Two possible joining modes are postulated at each oligomerization step. Catalytic site may arise on oligomer formed only by one of these modes. Effector acts by fastening together components of certain oligomeric form and increases the life time of this form. It leads to a shift of oligomer equilibrium and increases a proportion of effector-binding oligomers. Effectors-activators bind the oligomers carrying composite catalytic sites and effectors-inhibitors bind the oligomers, which do not carry active catalytic sites. Thus, catalytic activity control in such system is explained by effector-induced changes of a catalytic sites number, but not of a catalytic site activity caused by changes of subunit's tertiary structure. The postulates of the model do not contradict available experimental data and lead to a new type of general rate equation, which allows to describe and understand the specific kinetic behavior of allosteric enzymes as well as Michaelis type enzymes. All known rate equations of allosteric The equation was tested by modeling the kinetics of human erythrocyte phosphofructokinase. It enabled to reproduce quantitatively the 66 kinetic curves experimentally obtained for this enzyme under different reaction conditions.
Authors:
L N Drozdov-Tikhomirov; G I Skurida; A A Alexandrov
Related Documents :
6759869 - Non-coordinate synthesis of rna polymerase beta beta' subunits in a temperature-sensiti...
16460759 - Solution scattering reveals large differences in the global structures of type ii prote...
21851809 - Molecular simulations and solid-state nmr investigate dynamical structure in rhodopsin ...
8428909 - N-myristylation of the catalytic subunit of camp-dependent protein kinase conveys struc...
558799 - Effect of anisomycin on the cellular level of native ribosomal subunits.
3636229 - The inactive subunit of ruminant procarboxypeptidase a-s6 complexes. structural basis o...
23911089 - Redox-linked domain movements in the catalytic cycle of cytochrome p450 reductase.
21543329 - Crystal structure of the cytoplasmic phosphatase and tensin homolog (pten)-like region ...
21708939 - Metal fluoride complexes of na,k-atpase: characterization of fluoride-stabilized phosph...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of biomolecular structure & dynamics     Volume:  16     ISSN:  0739-1102     ISO Abbreviation:  J. Biomol. Struct. Dyn.     Publication Date:  1999 Feb 
Date Detail:
Created Date:  1999-07-09     Completed Date:  1999-07-09     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  8404176     Medline TA:  J Biomol Struct Dyn     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  917-29     Citation Subset:  IM    
Affiliation:
Institute of Molecular Genetics, Russian Academy of Sciences, Moscow. Drozdov@img.ras.ru
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Allosteric Regulation / physiology*
Catalytic Domain*
Erythrocytes / chemistry*
Humans
Kinetics
Models, Chemical*
Models, Statistical
Phosphofructokinase-1 / chemistry*
Protein Conformation
Chemical
Reg. No./Substance:
EC 2.7.1.11/Phosphofructokinase-1

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Computer simulation of the interaction of non-steroidal anti-inflammatory drugs: indoprofen and NS39...
Next Document:  Global and local structural properties of the principal neutralizing determinant of the HIV-1 envelo...