Cooperative binding of transition states in enzymatic catalysis

2009 ◽  
Vol 36 (S16) ◽  
pp. 301-309
Author(s):  
S. G. Jacchieri
Keyword(s):  
Enzymatic Catalysis ◽  
Transition States ◽  
Cooperative Binding

scholarly journals Introductory remarks to the second session

1981 ◽  
Vol 293 (1063) ◽  
pp. 63-64
Keyword(s):  
Steady State ◽  
Enzymatic Catalysis ◽  
Transition States ◽  
Phosphoglycerate Kinase ◽  
Reaction Rates ◽  
Steady State Rate ◽  
And Function ◽  
Enzyme Structure And Function ◽  
And Control

The four presentations in this session cover studies on different aspects of enzyme structure and function. They effectively illustrate how one has to combine different approaches to arrive at an understanding of enzymatic catalysis and control. Nowadays, the molecular description of an enzyme is hardly credible without detailed crystallographic information. Thus, Dr Blake’s paper on the structure of phosphoglycerate kinase is particularly relevant to our understanding of phosphate-transfer mechanisms. The question of the relation between structure in the solid and solution is still with us and n.m.r. has proved to be the best way to study the differences and similarities. M any enzyme substrate complexes have been ‘mapped’ in solution, by using the perturbation of the n.m.r. spectra by param agnetic centres as a measure of interatomic distances. How such results can lead to both structural and mechanistic information will be discussed by Dr Mildvan. To understand mechanisms we must also get some information about the nature of transition states. Here, stereochemical observations play an important role and Dr Lowe will describe some elegant work on the use of chiral phosphates in approaching this problem. Finally, it is important to describe structures, intermediates and transition states in terms of the kinetic behaviour of the enzyme and Dr Dalziel will give us an example of both steady-state and pre-steady-state rate studies. Measurements of reaction rates ultimately link studies on the isolated enzyme to their behaviour in vivo . As this last step in the sequence is not covered by the formal presentations at this meeting I should like to show briefly how n.m.r. can now be used to obtain fluxes of enzyme catalysed reactions in vivo both in the steady state and at equilibrium.

Matrix metalloproteinases: structure, functions and genetic polymorphism

2017 ◽  
pp. 14-23
Author(s):  
А.С. Шадрина ◽  
И.В. Терешкина ◽  
Я.З. Плиева ◽  
Д.Н. Кушлинский ◽  
Д.О. Уткин ◽  
...  
Keyword(s):  
Genetic Polymorphism ◽  
Matrix Metalloproteinases ◽  
Active Center ◽  
Human Body ◽  
Enzymatic Catalysis ◽  
Structure Functions ◽  
Zinc Ion ◽  
Etiological Factors ◽  
Mmp Genes

Матриксные металлопротеиназы (ММП) - ферменты класса гидролаз, осуществляющие ферментативный катализ с помощью связанного в активном центре иона цинка. Функции ММП разнообразны, и нарушение баланса их активности может быть одним из этиологических факторов различных заболеваний. В данном обзоре рассмотрена классификация ММП человека, особенности их структуры и регуляции, а также роль в физиологических и патологических процессах в организме человека. Приведен перечень наиболее изученных на настоящий момент полиморфных вариантов генов MMП, описаны их функциональные эффекты и представлены результаты ассоциативных исследований. Matrix metalloproteinases (MMPs) are enzymes of the hydrolase class that carry out enzymatic catalysis with the help of a zinc ion bound in the active center. MMP functions are diverse, and a disturbance in the balance of their activity may be one of the etiological factors of various diseases. In this review, the classification of human MMP, the features of their structure and regulation, as well as the role in physiological and pathological processes in the human body are considered. A list of the most studied polymorphic versions of MMP genes has been given, their functional effects have been described, and the results of associative studies have been presented.

Theoretical Computations on the Pyrolysis of Alkyl (dithio)acetates

2020 ◽  
Vol 17 (3) ◽  
pp. 224-233
Author(s):  
Xun Zhu ◽  
Chen Jian ◽  
Xiuqin Zhou ◽  
Abdullah M. Asiri ◽  
Khalid A. Alamry ◽  
...  
Keyword(s):  
Transition States ◽  
Membered Ring ◽  
Pyrolysis Process ◽  
Alkyl Esters ◽  
Charge Distributions ◽  
Theoretical Analyses

The pyrolysis of methyl alkyl esters I to III and dithioesters IV to VI were theoretically calculated. All possible pyrolysis paths were considered. Both esters and dithioesters presented three potential paths via six-, four- and five-membered ring transition states, respectively. The calculation processes were calculated using MP2/6-31G(d) set. In-depth theoretical analyses were also presented, including NBO related analyses, synchronicities, and charge distributions, to reveal the detailed pyrolysis process.

Sterically Crowded Heterocycles. X. A New Mechanistic Approach to the Ferricyanide Oxidation of 4,6'-Disubstituted 1-(Pyridin-2'-yl)-2,6-diphenylpyridinium Salts

1999 ◽  
Vol 64 (8) ◽  
pp. 1274-1294 ◽  
Author(s):  
Radek Pohl ◽  
Stanislav Böhm ◽  
Josef Kuthan
Keyword(s):  
Transition States ◽  
Oxidative Transformation ◽  
Steric Interactions ◽  
Radical Intermediates ◽  
Mechanistic Approach

The oxidations of the title perchlorates, bearing the sterically diverse 6'-substituents (H, Me, Et, i-Pr, n-Bu, t-Bu and Ph) in two series with the same 4-substituents (Ph and t-Bu) lead to pairs of isomeric 3',5-disubstituted (Z)-1'-phenyl-3'-(2-phenylimidazo[1,2-a]pyridin-3-yl)prop-2'- en-1'-ones and 3,6'-disubstituted [5-phenyl-1-(6'-pyridin-2'-yl)-1H-pyrrol-2-yl](phenyl)methanones except where the both variable substituents are t-Bu and then only pyrrolic product is formed. Considering steric interactions of the substituents in some intermediate and/or transition states a multistep mechanism for the oxidative transformation is proposed and supported by model PM3-PECI calculations of some radical intermediates.

scholarly journals 2PS034 Direct observation of cooperative binding of cofilin to actin filaments(The 50th Annual Meeting of the Biophysical Society of Japan)

2012 ◽  
Vol 52 (supplement) ◽  
pp. S115-S116
Author(s):  
Kimihide Hayakawa ◽  
Hitoshi Tatsumi ◽  
Takafumi Goto ◽  
Masahiro Sokabe
Keyword(s):  
Annual Meeting ◽  
Direct Observation ◽  
Actin Filaments ◽  
Cooperative Binding ◽  
Biophysical Society

scholarly journals Sequence-dependent cooperative binding of p53 to DNA targets and its relationship to the structural properties of the DNA targets

2010 ◽  
Vol 39 (5) ◽  
pp. 1919-1932 ◽  
Author(s):  
Itai Beno ◽  
Karin Rosenthal ◽  
Michael Levitine ◽  
Lihi Shaulov ◽  
Tali E. Haran
Keyword(s):  
Structural Properties ◽  
Cooperative Binding ◽  
Sequence Dependent
Sign in / Sign up

Export Citation Format

Share Document