H-Cys(Me)-OH

H-Cys(Me)-OH

Cytotoxic T lymphocyte epitope analogues containing cis- or trans-4-aminocyclohexanecarboxylic acid residues.[Pubmed:12110330]

Bioorg Med Chem. 2002 Sep;10(9):3061-6.

In order to improve the immunotherapeutical potential of H-Cys-Leu-Gly-Gly-Leu-Leu-Thr-Met-Val-OH (CLG) peptide, an Epstein-Barr virus (EBV) subdominant epitope derived from the membrane protein LMP2, we have synthesized and tested CLG analogues containing cis- and/or trans-4-aminocyclohexanecarboxylic acid (ACCA) replacing Gly-Gly and/or Thr-Met dipeptide units. All pseudopeptides were tested for metabolic stability and for their capacity to bind HLA-A2 molecules and to sensitize target cells to lysis. All new compounds exhibited higher enzymatic resistance compared to the original CLG and some trans-ACCA-derivatives were able to associate HLA-A2 and to efficiently stimulate CTL responses directed against the CLG natural epitope.

Conformational analysis of a potent SSTR3-selective somatostatin analogue by NMR in water solution.[Pubmed:16365912]

J Pept Sci. 2006 Feb;12(2):82-91.

The three-dimensional structure of a potent SSTR3-selective analogue of somatostatin, cyclo(3-14)H-Cys(3)-Phe(6)-Tyr(7)-D-Agl(8)(N(beta) Me, 2-naphthoyl)-Lys(9)-Thr(10)-Phe(11)-Cys(14)-OH (des-AA(1, 2, 4, 5, 12, 13)[Tyr(7), D-Agl(8)(N(beta) Me, 2-naphthoyl)]-SRIF) (peptide 1) has been determined by (1)H NMR in water and molecular dynamics (MD) simulations. The peptide exists in two conformational isomers differing mainly by the cis/trans isomerization of the side chain in residue 8. The structure of 1 is compared with the consensus structural motifs of other somatostatin analogues that bind predominantly to SSTR1, SSTR2/SSTR5 and SSTR4 receptors, and to the 3D structure of a non-selective SRIF analogue, cyclo(3-14)H-Cys(3)-Phe(6)-Tyr(7)-D-2Nal(8)-Lys(9)-Thr(10)-Phe(11)-Cys(14)-OH (des-AA(1, 2, 4, 5, 12, 13)[Tyr(7), D-2Nal(8)]-SRIF) (peptide 2). The structural determinant factors that could explain selectivity of peptide 1 for SSTR3 receptors are discussed.

Synthetic beta-endorphin-like peptide immunorphin binds to non-opioid receptors for beta-endorphin on T lymphocytes.[Pubmed:11786184]

Peptides. 2001 Dec;22(12):2009-13.

The synthetic decapeptide H-SLTCLVKGFY-OH (termed immunorphin) corresponding to the sequence 364-373 of the CH3 domain of human immunoglobulin G heavy chain was found to compete with [125I]beta-endorphin for high-affinity receptors on T lymphocytes from the blood of healthy donors (K(i) = 0.6 nM). Besides immunorphin, its synthetic fragments H-Val-Lys-Gly-Phe-Tyr-OH (K(i) = 15 nM), H-Leu-Val-Lys-Gly-Phe-Tyr-OH (K(i) = 8.0 nM), H-Cys-Leu-Val-Lys-Gly-Phe-Tyr-OH (K(i) = 3.4 nM), H-Thr-Cys-Leu-Val-Lys-Gly-Phe-Tyr-OH (K(i) = 2.2 nM), H-Leu-Thr-Cys-Leu-Val-Lys-Gly-Phe-Tyr-OH (K(i) = 1.0 nM) possessed the ability to inhibit specific binding of [125I]beta-endorphin to T lymphocytes. Tests of the specificity of the receptors revealed that they are not sensitive to naloxone and Met-enkephalin, i.e. they are not opioid receptors. K(d) values characterizing the specific binding of 125I- labeled immunorphin and its fragment H-Val-Lys-Gly-Phe-Tyr-OH to the receptors have been determined to be 7.4 nM and 36.3 nM, respectively.

N-imidazolebenzyl-histidine substitution in somatostatin and in its octapeptide analogue modulates receptor selectivity and function.[Pubmed:21806016]

J Med Chem. 2011 Sep 8;54(17):5981-7.

Despite 3 decades of focused chemical, biological, structural, and clinical developments, unusual properties of somatostatin (SRIF, 1) analogues are still being uncovered. Here we report the unexpected functional properties of 1 and the octapeptide cyclo(3-14)H-Cys-Phe-Phe-Trp(8)-Lys-Thr-Phe-Cys-OH (somatostatin numbering; OLT-8, 9) substituted by imBzl-l- or -d-His at position 8. These analogues were tested for their binding affinity to the five human somatostatin receptors (sst(1-5)), as well as for their functional properties (or functionalities) in an sst(3) internalization assay and in an sst(3) luciferase reporter gene assay. While substitution of Trp(8) in somatostatin by imBzl-l- or -d-His(8) results in sst(3) selectivity, substitution of Trp(8) in the octapeptide 9 by imBzl-l- or -d-His(8) results in loss of binding affinity for sst(1,2,4,5) and a radical functional switch from agonist to antagonist.

Synthesis, biological activity, and solution structures of a cyclic dodecapeptide from the EGF-2 domain of blood coagulation factor VII.[Pubmed:11437950]

J Pept Res. 2001 Jun;57(6):462-72.

The cyclic dodecapeptide, disulfide-cyclo-[H-Cys-Val-Asn-Glu-Asn-Gly-Gly-Cys(Acm)-Glu-Gln-Tyr-Cys-OH], which corresponds to the 91-102 sequence of the second epidermal growth factor domain of human blood coagulation factor VII, was synthesized using solid-phase procedures. It was shown to be an inhibitor at the key step in the induction of coagulation by the extrinsic pathway, i.e. the factor VII/tissue factor-catalyzed activation of coagulation factor X. The solution structure of this peptide was investigated by NMR spectroscopy and was computer-modeled via molecular mechanics. Structures were calculated based on 112 distance and nine dihedral angle constraints. The resulting backbone structures were classified into two structural subsets: one which exhibited a twisted '8'-shaped folding and another describing an open, circular 'O' outline. The local backbone structures of segments Asn3-Glu4-Asn5, Gly7-Cys8 and Gln10-Tyr11 were well preserved among the two subsets. Apart from the unrestrained N- and C-termini, Gly6 and Glu9 sites exhibited marked local disorder between the two subsets, suggesting localized flexible hinges likely to govern tertiary structure interconversion between the two subsets. Two transient hydrogen bonds were identified from pH chemical shift titrations by matching the pKa values of NH and carboxylate groups, which supported the occurrence of the '8' structure, and agreed with temperature coefficients of peptidyl NH resonances. Structure-function relationships of the peptide were discussed in terms of the likely physiological function of the disulfide-bonded loop in factor VII which the peptide represents.

S-Methyl-L-cysteine is a natural product that acts as a substrate in the catalytic antioxidant system mediated by methionine sulfoxide reductase A (MSRA), with antioxidative, neuroprotective, and anti-obesity activities.

H-Cys(Me)-OH,1187-84-4,L-S-Methylcysteine,Natural Products,Amino Acids and Derivatives, buy H-Cys(Me)-OH , H-Cys(Me)-OH supplier , purchase H-Cys(Me)-OH , H-Cys(Me)-OH cost , H-Cys(Me)-OH manufacturer , order H-Cys(Me)-OH , high purity H-Cys(Me)-OH