Peptides oligo

Androulakis, I. R G. D. Maranas and C. A. Floudas. Global Minimum Potential Energy Conformation of Oligo Peptides. J Glob Opt 11 1-34 (1997). 

Dioxopiperazines are products of sometimes unwanted cyclizations of the N-terminal residues of di- and oligo-peptides and proteins. As a model for this process. 

Kajimoto O, Saito M, Hagino H, Nishimura A, Kajimoto Y, Hirata H. (2004) Hypotensive effect and safety of the granular foods containing oligo peptides derived from nori Porphya yezoensis) in subjects with high-normal blood pressure. J Nutr Food 7 43-58. 

Formation of an amide bond (peptide bond) will take place if an amine and not an alcohol attacks the acyl enzyme. If an amino acid (acid protected) is used, reactions can be continued to form oligo peptides. If an ester is used the process will be a kinetically controlled aminolysis. If an amino acid (amino protected) is used it will be reversed hydrolysis and if it is a protected amide or peptide it will be transpeptidation. Both of the latter methods are thermodynamically controlled. However, synthesis of peptides using biocatalytic methods (esterase, lipase or protease) is only of limited importance for two reasons. Synthesis by either of the above mentioned biocatalytic methods will take place in low water media and low solubility of peptides with more than 2-3 amino acids limits their value. Secondly, there are well developed non-biocatalytic methods for peptide synthesis. For small quantities the automated Merrifield method works well. 

Di- and oligo-peptides with a terminalo-aminophosphonous acid residue have been prepared by coupling with N-hydroxy succinimide esters of N-benzyloxycarbonylamino acids or peptides. 

Wang XF, Ji J (2009) Postdiffusion of oligo-peptide within exponential growth multilayer films for localized peptide delivery. Langmuir 25 11664-11671... 

III. Hydrolases Hydrolysis reaction in H20 Lipase Cellulase, Hyaluronidase Papain Polyesters, Cellulose, Glycosamino- glycans (Oligo)peptides 4, 5, 11, 12,13,14, 15,16... 

The molecularly imprinted copolymer of 2-hydroxyethyl methacrylate (HEMA) and p-CyD-coupled HEMA was synthesized in chloroform to study its interaction with a pair of steroids cholesterol and testosterone [42]. The molecularly imprinted copolymer was found to absorb the print molecule several times better than an imprinted poly HEMA. Asanuma et al. [44] concluded that cholesterol binding by the HEMA polymer was not due to CyD inclusion because no inclusion of CyD to cholesterol can form in chloroform. Another strategy developed for imprinting using CyD elements is the vinyl CyD (Table 1 and 10.3(A)), which has been successfully applied for imprinting antibodies, oligo-peptides [45], and vancomycin [46[. 

FIGURE 7.28 (a) Chemical structure of a PPV-like oligo peptide (b) PL spectrum of the oligo peptide. The... 

The oligo-peptide conjugate is then purified on a Delta-Pak C18 15 xm 300A column (Waters) and characterized by MALDl-MS (Voyager STR, Applied BioSystems). 

He, H., Chen, X., Sun, C., Zhang, Y, Gao, P. Preparation and functional evaluation of oligo-peptide-emiched hydrolysate from shrimp (Acetes chinensis) treated with crude protease from Bacillus sp. SM9WU. Bioresour Technol 2006,97, 385-390. 

Most of the peptide syntheses catalyz l by enzymes concern the coiq>ling td two differrait amino adds or two diffooit oligo-peptides which are important building tdocks peptide bond formation has been reviewed precisely in the literature [45, 46]. In these reactmns, a reversed reaction of proteases was utilized for the peptide bond formation. 

The second stage of protein degradation is the transport of di-, tri-, and oligo-peptides into the cell. Three oligo-, di-, and tri-peptide transport systems (Opp, Dpp andDtpT, respectively) have been described in LAB. Lact. acidophilus, Lactobacillus brevis, Lact. casei, Lactobacillus rhamnosus, and L. lactis, possess all three of these peptide transport systems. Some Lact. helveticus strains, such as DPC4571, also have three peptide transport systems, while others, such as HIO, only have two (Opp and DtpT). These results indicate that the proteolytic systems differ between different strains of even the same species. Finally, Lact. reuteri only has one functional peptide transport system (DtpT) (Liu et al. 2010). 

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