Amino peptidases metal complexes

Amino peptidases zinc, 6,606 Amino sugars metal complexes geochemistry, 6, 867 Ammonia... 

The cobalt(III)-promoted hydrolysis of amino acid esters and peptides and the application of cobalt(III) complexes to the synthesis of small peptides has been reviewed. The ability of a metal ion to cooperate with various inter- and intramolecular acids and bases and promote amide hydrolysis has been investigated. The cobalt complexes (5-10) were prepared as potential substrates for amide hydrolysis. Phenolic and carboxylic functional groups were placed within the vicinity of cobalt(III) chelated amides, to provide models for zinc-containing peptidases such as carboxypeplidase A. The incorporation of a phenol group as in (5) and (6) enhanced the rate of base hydrolysis of the amide function by a factor of 10 -fold above that due to the metal alone. Intramolecular catalysis by the carboxyl group in the complexes (5) and (8) was not observed. The results are interpreted in terms of a bifunctional mechanism for tetrahedral intermediate breakdown by phenol. 

It is not uncommon that bacteria do not develop weU even when aU the mentioned parameters are optimal since the composition of wine is very complex. From a nutritional point of view, essential elements such as carbon, nitrogen, vitamins, and metal sources are appropriately represented in the wine. Pentoses and hexoses present after AF, in concentrations of about sevraal hundred mg/1, are sufficient to produce the necessary biomass to carry out the MLF In addition, the bacteria glycosidases and peptidases hydrolyze numerous glycosylated and peptide molecules into sugars and amino acids, which they then use. By contrast, grape molecules, such as some phenohc compounds, may be toxic but they may have positive effects as has also been demonstrated (Theobald et al. 2008 Cairpos et al. 2009). 

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