Peptide chemical

In contrast to the finding by 1SN NMR that 85 % of the total soil N occurs in proteins or peptides, chemical methods show that only about 40 % of the total soil N occurs in proteins. [4] What are the reasons for these wide divergencies To provide answers to these questions, it may be useful to consider the following ... 

This experiment represents a scenario when an organic lead compound is available. We chose morphine, a known opiate receptor ligand of non-peptide chemical nature, as a hypothetical lead compound. The averaged frequency distribution based on all four SA runs is obtained (data not shown). The most frequent building block was Dll. Building blocks DIO, D12, D14, and 03 were less frequent, but all above random expectation. 

In addition to homodetic cyclic peptides, chemical ligation methods have been developed that lead to heterodetic cyclic peptides containing thiazolidine. 158-161 ... 

Three main categories of processes are used for the synthesis of peptides chemical synthesis, extraction from natural substances, and biosynthesis. On further scrutiny, almost 10 distinct synthetic methods can be distinguished (see Table 4.2). For the synthesis of some peptides, more than one method is used, including chemical (solution or solid phase) synthesis and recombinant biotechnology for salmon calcitonin, extraction from pancreas, semisynthesis, and recombinant biotechnology for insulin. 

Proteins, peptides, and other polymeric macromolecules display varying degrees of chemical and physical stability. The degree of stability of these macromolecules influence the way they are manufactured, distributed, and administered. Chemical stability refers to how readily the molecule can undergo chemical reactions that modify specific amino-acid residues, the building blocks of the proteins and peptides. Chemical instability mechanisms of proteins and peptides include hydrolysis, deamidation, racemization, beta-elimination, disulfide exchange, and oxidation. Physical stability refers to how readily the molecule loses its tertiary and/or sec-... 

Fig.3 The dependences on the dihedral angles(< >,i /), of the isotropic chemical shielding constant for the L-alanine residue Cp- (a)and Ca-(b) carbons in peptides. Chemical shielding calculations were carried out using the GIAO-CHF method with 4-31G ab initio MO basis set. The 4-31G optimized geometries for the model molecules, N-acetyl-N -methyl-L-alanineamide, were employed.

Expressed peptide Chemical synthesis Chemical synthesis Chemical synthesis... 

Violand, B. N., and Siegel, N. R. (2000), Protein and peptide chemical and physical stability, in Reid, R., Ed., Protein and Peptide Drug Analysis, Marcel Dekker, New York. 

Camarero, J. A., Fushman, D., Cowburn, D., and Muir, T. W. (2001) Peptide chemical ligation inside living cells in vivo generation of a circular protein domain. Bioorg. Med. Chem. 9, 2479-2484. 

Figure 2 A selection of nonribosomal peptides. Chemical and structural features that contribute to the vast diversity of this class of metabolites are highlighted Heterocycle (bacitracin), lactone (surfactin, daptomycin), ornithine and lactam (Tyrocidine), sugar, chlorinated aromats, C-C crosslink (Vancomycin), N-formyl groups (Coelichelin and linear gramicidin), fatty acid (daptomycin), dihydroxybenzoate and trimeric organization (bacillibactin), dimeric organization (gramicidin S), and ethanolamine (linear gramicidin).

Sohma Y, Kiso Y. Click peptides -chemical biology-oriented synthesis of Alzheimer s disease-related amyloid (> peptide (Afl) analogues based on the O-acyl isopeptide method . Chem-BioChem. 2006 7 1549-1557. 

GM van Bleek and SG Nathenson (1993) in "Naturally Processed Peptides", Chemical Immunology vol. 57, A Sette (ed.), Karger Publishing, Basel, pp 1-17. 

Humphrey, J. M. and Chamberlin, A. R. (1997) Chemical synthesis of natural product peptides coupling methods for the incorporation of noncoded amino acids into peptides. Chemical Reviews, 97, 2243-2266. 

Violand BN, Siegel NR. Protein and peptide chemical and physical stability. In Reid RE, ed. Peptide and Protein Drug Analysis. New York Marcel Dekker, 2000 257-284. 

Reubsaet JLE et al. Analytical techniques used to study the degradation of proteins and peptides chemical instability. J Pharm Biomed Anal 1988 17 955 - 978. 

Peptides Chemically bonded L-Val-L-Ala-L-Pro Citrate buffers at various pH values At 254 and 280 nm 120... 

Reflect and Apply Consider the peptides Gly—Pro—Ser—Glu— Thr (open chain) and Gly—Pro—Ser—Glu— Thr with a peptide bond linking the threonine and the glycine. Are these peptides chemically the same ... 

Figure 6.7-3. Precursors used for residualizing radio-iodination of monoclonal antibodies and peptides. Chemically reactive groups on the precursors are shaded, and site for radio-iodination of the precursor is indicated in black and with an asterisk. SIB N-succinimidyi-3-iodobenzoate SIPC N-succinimidyl 5-iodo-3-pyridinecarboxyiate SGMIB N-succinimidyl 4-guanidinomethyl-3-iodobenzoate.

Compound name(s) systematic and trivial Amino-acid sequence for peptides Chemical formula Author name... 

K.W. Waddell, E.Y. Chekmenev, R.J. Wittebort, Peptide chemical sliielding and electric field gradient tensors, J. Phys. Chem. B 110 (2006) 22935. 

Ahmed, S., Kaur, K., 2009. The proteolytic stability and cytotoxicity studies of L-aspartic acid and L-diaminopropionic acid derived fLpeptides and a mixed a/p-peptide. Chemical Biology Drug Design 73,545-552. 

Macrocyclic a-Helical Peptide Chemical Biology and Drug Design... 

Oxytocin 9 amino adds cyclic peptide Chemical synthesis Induction of uterine contractions to promote childbirth... 

Vassopressin and desmopressin 9 amino adds cyclic peptides Chemical synthesis Antidiuretic hormones used in treatment of diabetes insipidus... 

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