Amide bonds are fundamental products in biochemistry, forming peptides critical to protein formation, but amide also detected sterile environments and abiotic synthesis experiments. The formation of may represent a prerequisite the origin life. Here we report thermodynamic models that predict optimal conditions for bond across geologically relevant ranges temperature, pressure, pH. We modeled a...

The gastric ganglion is the largest visceral ganglion in cephalopods. It is connected to the brain and is implicated in regulation of digestive tract functions. Here we have investigated the neurochemical complexity (through in silico gene expression analysis and immunohistochemistry) of the gastric ganglion in Octopus vulgaris and tested whether the expression of a selected number of genes was...

• Modified peptides: these molecules contain relatively small modifications that do not modify the peptide bond, and thus they still possess a chemical structure of peptide nature. • Pseudopeptides: in these compounds partial modifications of either peptide bonds or side-chains are introduced, contributing to the generation of molecules possessing a chemical structure of only partial peptide na...

Glucagon-like peptide 1 (GLP-1) lowers glycemia by modulating gastric emptying and endocrine pancreatic secretion. Rapidly after its secretion, GLP-1-(7-36) amide is degraded to the metabolite GLP-1-(9-36) amide. The effects of GLP-1-(9-36) amide in humans are less well characterized. Fourteen healthy volunteers were studied with intravenous infusion of GLP-1-(7-36) amide, GLP-1-(9-36) amide, o...

introduction: bombesin (bn), a 14-amino acid neuropeptide, shows high affinity for the human grp (gastrin releasing peptide) receptors, which are overexpressed by a variety of cancers, including prostate, breast, pancreas, gastrointestinal, and small cell lung cancer. aim was to prepare [6-hydrazinopyridine-3-carboxylic acid (hynic0), d-tyr6, d-trp8] - bn [6-14] nh2 that could be easily labeled...

The structure of melittin in the presence of dioleoylphosphatidylcholine (DOPC) was investigated using hydrogen deuterium (H/D) exchange in conjunction with collision induced dissociation (CID) in an rf-only hexapole ion guide with electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR MS). The deuterium incorporation into backbone amide hydrogens of mel...

Neutral trialanine (Ala3), which is geometrically constrained to have its peptide bond at Phi and Psi angles of alpha-helix and PPII-like conformers, are studied at the B3LYP/6-31+G(d,p) level of theory to examine vibrational interactions between adjacent peptide units. Delocalization of the amide I, amide II, and amide III3 vibrations are analyzed by calculating their potential energy distribu...

In vivo13C magnetic resonance spectroscopy (MRS) is a unique and effective tool for studying dynamic human brain metabolism and the cycling of neurotransmitters. One of the major technical challenges for in vivo13C-MRS is the high radio frequency (RF) power necessary for heteronuclear decoupling. In the common practice of in vivo13C-MRS, alkanyl carbons are detected in the spectra range of 10-6...

  Introduction: Bombesin (BN), a 14-amino acid neuropeptide, shows high affinity for the human GRP (gastrin releasing peptide) receptors, which are overexpressed by a variety of cancers, including prostate, breast, pancreas, gastrointestinal, and small cell lung cancer. Aim was to prepare [6-hydrazinopyridine-3-carboxylic acid (HYNIC0), D-Tyr6, D...