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Multinuclear metalloenzymes

Multimetallic fullerene adducts, 44 24, 26-28 Multinuclear metalloenzymes, 44 247-258 nt Multiple bonds, 33 260 structure of and proofs for, 33 256 Muonic radical, formation and reactions of, 28 122-130... [Pg.194]

Many enzymes contain two or more metal ions in the active site, exploiting collaboration among the metal centers in the catalytic action. Examples of multinuclear metalloenzymes catalyzing hydrolysis of acyl derivatives and related compounds are methionine aminopeptidase (4), metallo-p-lactamase... [Pg.81]

Multinuclear metallocatalyst BJ manifested both catalytic activity and substrate selectivity in the hydrolysis of small peptides. The metal centers of the artificial active site of BJ were utilized both in substrate recognition and in catalytic conversion. The structure of the active site obtained by using the bowlshaped molecule, however, is unknown. In addition, it is not possible to synthesize a variety of artificial multinuclear metalloenzymes by the method of transferring catalytic elements confined in a prebuilt cage to a synthetic polymer. [Pg.108]

Likhtenshtein G.I, (1979a) Multinuclear Redox Metalloenzymes, Moscow, Nauka. [Pg.208]

Second, since the small number of atoms bind firmly to the underlying support, it may be more appropriate to regard the nanocluster as a molecular entity with its activity and selectivity being more like that of multinuclear single-site catalysts, such as that found in many metalloenzymes, e.g., hydrogenases, than of a bulk metal or alloy. [Pg.466]

From the theoretical standpoint, it is rather appropriate to regard these cluster catalysts as molecular entities with their activity and selectivity being more like that of a multinuclear single-site catalyst (such as that found in certain metalloenzymes like hydrogenases [56] and other bimetallic molecular clusters [57]) than of the much larger nanoparticle catalysts (of Au [58] or Au-Pd [34]) which fall in the range 2-5 nm diameter and contain more than a hundred times as many atoms. It is well... [Pg.470]

An effective multinuclear artificial metalloenzyme would be obtained if an artificial active site comprising of two or more proximal metal centers is designed. A trinuclear artificial metallopeptidase was prepared by using BH... [Pg.105]

Considerable attention has been given to the synthesis of compounds in which a single mono- or multinuclear coordination unit is at the center of a dendrimer array. These systems have been prepared by the construction of ligands with pendant dendritic wedges with subsequent convergent assembly upon coordination of a metal ion at the center or by covalent synthesis of an appropriate dendrimer-functionalized macrocyclic core. The primary interest for the study of such compounds lies in the very unusual, usually hydrophobic, environment in which the metal(s) at the center find themselves. This environment has been likened to that at the active site of a metalloenzyme and numerous studies have dealt with the catalytic and biomimetic activity of such conjugates. A general introduction to the area and the concept of chemistry within dendrimers is available. " The term dendrizyme has been used to describe these systems. [Pg.293]

Metal-mediated reactions involving water are essential to life and catalytic industrial processes [1-3]. In biological systems, metalloenzymes containing various divalent metal ions catalyze the hydrolysis of amide, carboxylic ester and phosphate ester bonds using both mono- and multinuclear active-site structural motifs [4—6], Mononuclear metal centers are also found within the active sites of enzymes that catalyze the hydration, or the addition of water, to CO2 [Zn(II)] and nitriles [Co(III)/Fe(III)j [7-10]. In many of these processes, formation of a metal hydroxide moiety via deprotonation of a metal-coordinated water molecule is a key proposed step in the reaction pathway. Thus, a substantial amount of research over the past several years has been directed at dehneating how the structural and electronic environments of biological metal ions influence the pKa of a metal-bound water molecule. In this regard, studies directed at the preparation, characterization and elucidation of the reactivity of discrete metal aqua and hydroxo complexes have been paramoimt [11-13]. [Pg.287]


See other pages where Multinuclear metalloenzymes is mentioned: [Pg.81]    [Pg.81]    [Pg.247]    [Pg.769]    [Pg.555]    [Pg.134]    [Pg.247]    [Pg.1415]    [Pg.171]    [Pg.535]   
See also in sourсe #XX -- [ Pg.247 , Pg.248 , Pg.249 , Pg.250 , Pg.251 , Pg.252 , Pg.253 , Pg.254 , Pg.255 , Pg.256 , Pg.257 ]

See also in sourсe #XX -- [ Pg.247 , Pg.248 , Pg.249 , Pg.250 , Pg.251 , Pg.252 , Pg.253 , Pg.254 , Pg.255 , Pg.256 , Pg.257 ]




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