Wheat carboxypeptidase II has been isolated from wheat bran by affinity chromatography and its enzymatic properties and amino acid sequence has been determined. The enzyme is a dimer of molecular weight around 110,000 with each monomer composed of two peptide chains, an A-chain and a B-chain, linked by disulfide bridges. The A-chain exists in two forms, one, the A'-chain, being three amino acid...

Restriction endonuclease NarI cleaves DNA using a two-site mechanism, placing it in the Type IIe class of restriction endonucleases. Although these enzymes have very useful recognition sequences, the two-site mechanism limits the practical application. Site preferences often cause incomplete substrate digestion. Oligonucleotide activation of NarI eliminates incomplete digestions, making it poss...

Kinases serve crucial roles in many cellular signaling pathways that process and transfer information. When signaling kinases phosphorylate two targets, these can serve as branch points that distribute information among two pathways. Responses to stimuli transmitted by activated kinases show high levels of cell-to-cell variation that influence cellular function. We ask how fluctuations around a...

Peptide trimming in the endoplasmic reticulum (ER), the final step required for the generation of most HLA class I-binding peptides, implicates the concerted action of two aminopeptidases, ERAP1 and ERAP2. Because defects in the expression of these peptidases could lead to aberrant surface HLA class I expression in tumor cells, we quantitatively assayed 14 EBV-B cell lines and 35 human tumor ce...

SUMMARY The development of robust high-performance liquid chromatography (HPLC) technologies continues to improve the detailed analysis and sequencing of glycan structures released from glycoproteins. Here, we present a database (GlycoBase) and analytical tool (autoGU) to assist the interpretation and assignment of HPLC-glycan profiles. GlycoBase is a relational database which contains the HPLC...

Gap junctions play important roles in auditory function and skin biology; mutations in the Cx26 (connexin26) gene are the predominant cause of inherited non-syndromic deafness and cause disfiguring skin disorders. Mass spectrometry (MS) was used to identify PTMs (post-translational modifications) of Cx26 and to determine whether they occur at sites of disease-causing mutations. Cx26 was isolate...

The main focus of enzymology is on the enzyme rates, substrate structures, and reactivity, whereas the role of solvent dynamics in mediating the biological reaction is often left aside owing to its complex molecular behavior. We used integrated X-ray- and terahertz- based time-resolved spectroscopic tools to study protein-water dynamics during proteolysis of collagen-like substrates by a matrix...

Hemicelluloses are abundant polysaccharides in the plant cell walls. They tether the celulose microfibrils and participate in the control of the cell expansion together with expansins (Cosgrove, 1998) [1]. The hemicellulose may present a variety of decorating side chains, including feruloyl and acetyl substituents. The ferulic acid may be esterified to the hemicellulose and crosslinked to ligni...

Here the relation between digestion of proteins by trypsin covalently bound to paper and in-solution is investigated. The acting on bound. A concentration 0.5% (w/v) results in highest activity all concentrations tested. Additionally, it can be seen that on-paper has retained approx. 50% its activity. Unlike in-solution, stability smart proteolysis samplers was regarded stable for at least four...