The asymmetric phase-transfer catalytic alkylation of peptides has been achieved by the use of designed C(2)-symmetric chiral quaternary ammonium bromide 1 as catalyst. Excellent stereoselectivities were uniformly observed in the alkylation with a variety of alkyl halides and the efficiency of the transmission of stereochemical information was not affected by the side-chain structure of the pre...

Domesticated animals have a large variety of antimicrobial peptides that serve as natural innate barriers limiting microbial infection or, in some instances, act as an integral component in response to inflammation or microbial infection. These peptides differ in size, composition, mechanisms of activity and range of antimicrobial specificities. They are expressed in many tissues, polymorphonuc...

Formation of plaque by fibrils of β-amyloid (Aβ) peptide in the brain is the characteristic feature of Alzheimer disease (AD). Inhibition of the process of aggregate formation from Aβ-monomer and destabilization of the aggregate could be useful for prevention and propagation of the disease respectively. Russell's viper venom (RVV) contains protein(s) that destabilize Aβ aggregates as revealed f...

The aetiological relationship of wheat gluten and gliadin, and some peptides obtained from them by peptic-tryptic digestion, to the clinical and small intestinal mucosal abnormalities of coeliac disease has been demonstrated in several studies (Dicke, 1950; Anderson, Frazer French, Gerrad, Sammons, and Smellie, 1952; Sheldon and Lawson, 1952; Dicke, Weijers, and van de Kamer, 1953; van de Kamer...

Small ubiquitin-like modifiers (SUMO) and ubiquitin are frequent post-translational modifications of proteins that play pivotal roles in all cellular processes. We previously reported mass spectrometry-based proteomics methods enable profiling lysines modified by endogenous SUMO or an unbiased manner, without the need for genetic engineering. Here we investigated applicability precursor filteri...

The objective of this study was to elucidate the metabolic fate peptides in a rice protein hydrolysate (RPH) rats. Peptides present RPH and its vitro exopeptidase digest were identified using liquid chromatography–tandem mass spectrometry. One hour after an oral administration (250 mg/kg body weight), levels exopeptidase-resistant pyroglutamyl lumen ileal tissue significantly increased, whereas...

BACKGROUND Low-temperature techniques that prevent protein denaturation are being used to extract collagen from fish skin for cosmetic purposes. These extracts contain collagen with its triple helix structure preserved, as well as a number of other proteins. OBJECTIVES The aim of the study was to investigate collagen extracts from the skin of silver carp for the presence of small-molecule pep...

Poly(ethylene glycol) (PEG) has been studied as a drug-carrier for proteins, but not for small peptides. Laminin, a cell adhesive protein, has Tyr-Ile-Gly-Ser-Arg (YIGSR) sequence and peptides containing this sequence inhibit experimental metastasis. We have studied PEG hybrids of YIGSR and other small laminin-related peptides. In a previous paper, we reported preparation of YIGSR-PEG hybrids b...

A polypeptide from tobacco has been found to be processed into multiple functional peptides, each with independent hormone-like activities. This adds to a growing set of small peptides known to function as signal molecules in plants.