Allosteric regulation of aspartate transcarbamoylase. Analysis of the structural and functional behavior in terms of a two-state model

Biochemistry ◽  
1977 ◽  
Vol 16 (23) ◽  
pp. 5091-5099 ◽  
Author(s):  
G. J. Howlett ◽  
Michael N. Blackburn ◽  
John G. Compton ◽  
H. K. Schachman
Keyword(s):  
Allosteric Regulation ◽  
State Model ◽  
Aspartate Transcarbamoylase ◽  
Functional Behavior ◽  
Two State Model

Allosteric theory

Hemoglobin ◽  
2018 ◽  
pp. 42-57
Author(s):  
Jay F. Storz
Keyword(s):  
Active Site ◽  
Binding Sites ◽  
Allosteric Regulation ◽  
Theoretical Models ◽  
State Model ◽  
Regulatory Control ◽  
Indirect Interaction ◽  
Protein Activity ◽  
Conformational States ◽  
Two State Model

Chapter 3 provides a brief overview of allostery, the modulation of protein activity that is caused by an indirect interaction between structurally remote binding sites. In this mode of intramolecular regulatory control, the binding of ligand at a protein’s active site is influenced by the binding of another ligand at a different site in the same protein. This interaction at a distance is mediated by a ligation-induced transition between alternative conformational states. Hemoglobin is regarded as the “allosteric paradigm,” and the oxygenation-linked transition between alternative quaternary conformations provides a textbook example of how allostery works. This chapter reviews different theoretical models, such as the Monod-Wyman-Changeux “two-state” model, to explain the allosteric regulation of hemoglobin function.

Polarographic studies on renaturation of urea-denatured human serum albumin

1989 ◽  
Vol 54 (2) ◽  
pp. 536-543 ◽  
Author(s):  
Josef Chmelík ◽  
Pavel Anzenbacher ◽  
Vítěz Kalous
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Irreversible Process ◽  
State Model ◽  
Native Protein ◽  
Main Components ◽  
Two State Model ◽  
Kinetics Of

The renaturation of the two main components of human serum albumin, i.e. of mercaptalbumin and nonmercaptalbumin, was studied polarographically. It has been demonstrated that renaturation of both proteins after 1-min denaturation in 8M urea is reversible. By contrast, renaturation after 200 min denaturation in 8M urea is an irreversible process; the characteristics of renatured mercaptalbumin differ more from the properties of the native protein than the characteristics of nonmercaptalbumin. The studies of the kinetics of renaturation of both proteins have shown that the renaturation can be represented by a two-state model. This means that the existence of stable intermediary products during the renaturation process was not determined polarographically.

An ensemble view of thrombin allostery

2012 ◽  
Vol 393 (9) ◽  
pp. 889-898 ◽  
Author(s):  
Bernhard C. Lechtenberg ◽  
Stefan M.V. Freund ◽  
James A. Huntington
Keyword(s):  
Structural Changes ◽  
Allosteric Regulation ◽  
Monovalent Cation ◽  
Coagulation Cascade ◽  
General View ◽  
Multiple Substrates ◽  
Dynamic View ◽  
Static View ◽  
Two State Model ◽  
The Continuum

Abstract Thrombin is the central protease of the coagulation cascade. Its activity is tightly regulated to ensure rapid blood clotting while preventing uncontrolled thrombosis. Thrombin interacts with multiple substrates and cofactors and is critically involved in both pro- and anticoagulant pathways of the coagulation network. Its allosteric regulation, especially by the monovalent cation Na+, has been the focus of research for more than 30 years. It is believed that thrombin can adopt an anticoagulant (‘slow’) conformation and, after Na+ binding, a structurally distinct procoagulant (‘fast’) state. In the past few years, however, the general view of allostery has evolved from one of rigid structural changes towards thermodynamic ensembles of conformational states. With this background, the view of the allosteric regulation of thrombin has also changed. The static view of the two-state model has been dismissed in favor of a more dynamic view of thrombin allostery. Herein, we review recent data that demonstrate that apo-thrombin is zymogen-like and exists as an ensemble of conformations. Furthermore, we describe how ligand binding to thrombin allosterically stabilizes conformations on the continuum from zymogen to protease.

Two-state model for bacterial chemoreceptor proteins

1984 ◽  
Vol 176 (3) ◽  
pp. 349-367 ◽  
Author(s):  
Sho Asakura ◽  
Hajime Honda
Keyword(s):  
State Model ◽  
Two State Model

Worklife and Unemployment: A New Consideration

2021 ◽  
Author(s):  
David I. Rosenbaum ◽  
Kalana Jayanetti
Keyword(s):  
Initial Data ◽  
State Model ◽  
Inactive State ◽  
Three State Model ◽  
Good Proxy ◽  
Two State Model

Abstract Do traditional two-state worklife estimates need adjustment for unemployment? To answer, an augmented three-state model classifies individuals as either 1) employed; 2) unemployed; or 3) inactive but not marginally attached. Periods of unemployment may reduce worklives; however, removal of those marginally attached or discouraged from the inactive state raises worklives. The three-state model results are compared to worklife estimates from the same initial data using the traditional two-state model. Results show that in many cases, the two-state model results are a good proxy for the three-state results that control for unemployment.

Sign in / Sign up

Export Citation Format

Share Document