Enzymatic reaction cross linking

Then when amino groups are cross-linked on the right spots, the enzyme is blocked out from further HP decomposition reactions. Of course, the dialdehydes are not specific either to the enzyme or to the bacteria, but there are enough dialdehyde molecules present to decrease the enzymatic activity to an acceptable level. 

This book gives a comprehensive coverage of the synthesis of polymers and their reactions, structure, and properties. The treatment of the reactions used in the preparation of macromolecules and in their transformation into cross-linked materials is particularly detailed and complete. The book also gives an up-to-date presentation of other important topics, such as enzymatic and protein synthesis, solution properties of macromolecules, polymer in the solid state. The content and presentation of Professor Vollmert s book is more encompassing than most existing treatises, and its numerous figures and tables convey a wealth of data, never, however, at the expense of intellectual clarity or educational value. 

Collagen cross-links. Besides amide bonds between amino acids in the same a chain, bonds between amino acid side chains of different a chains can form "cross-links". These bonds originate from enzymatically-oxidized side chains of lysine and hydroxylysine residues. The oxidized residues react with other lysine and hydroxylysine residues, forming difunctional products. Reactions of such products with oxidized lysine or hydroxylysine yield trifunctional cross-links (Reiser et al., 1992). 

Enzymatic phosphorylation by phosphorylases and phosphatases produces phosphoesters such as phosphoserine and phosphothreonine. Chemical phosphorylation of proteins changes their functional properties, improving them sometimes (Yoshikawa et al., 1981 Hirotsuka et al., 1984 Huang and Kinsella, 1986 Chobert etal, 1989 Matheis, 1991). However, the properties of the phosphorylated proteins depend entirely on the degree of denaturation and substitution defined by the reaction conditions and the protein (Medina etal, 1992 Sitohy etal, 1994). Casein was phosphorylated by the commonly used methods, characterized by use of excessive amounts of phosphorus oxychloride and with important additions of concentrated inorganic bases (Matheis et al, 1983 Medina et al, 1992). Thus, obtained phosphorylated caseins were highly cross-linked and partially insoluble and difficult to characterize. Hence, there arose a need to produce monomeric over-phosphorylated caseins more suitable for use and for study of their... 

The first enzymatically coupled FET is sensitive to penicillin (1). It is composed of two separate FET chips and a silver/silver chloride reference electrode (see Fig. 4). Penicillinase, which produces protons during catalysis, is immobilized on one of the FET chips by utilizing the glutaraldehyde protein cross-linking reaction. The membrane of the reference FET chip contains immobilized bovine serum albumin. 

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