Protein and Peptide Letters - Volume 18, Issue 4, 2011

It is well known that the primary sequence of a protein governs its three dimensional (3D) structure [1], on which, we suppose, molecular behavior and biological function of the protein are relied. It is more than 50 years since the first protein structure, hemoglobin, was solved in atomic resolution by x-ray crystallography [2]; people believe that the static structure of a protein is the fundamental for its unique function. Wit Read More

Enzymatic catalysis has conflicting structural requirements of the enzyme. In order for the enzyme to form a Michaelis complex, the enzyme must be in an open conformation so that the substrate can get into its active center. On the other hand, in order to maximize the stabilization of the transition state of the enzymatic reaction, the enzyme must be in a closed conformation to maximize its interactions with the transition Read More

Despite impressive progress in protein engineering and design, our ability to create new and efficient enzyme activities remains a laborious and time-consuming endeavor. In the past few years, intricate combinations of rational mutagenesis, directed evolution and computational methods have paved the way to exciting engineering examples and are now offering a new perspective on the structural requirements of enzym Read More

In this article we review the current status of our understanding of membrane mediated interactions from theory and experiment. Phenomenological mean field and molecular models will be discussed and compared to recent experimental results from dynamical neutron scattering and atomic force microscopy.

Aβ is widely recognized as a key molecule in Alzheimer's disease, causing neurotoxicity through Aβ aggregates, Aβ oligomers and fibrils. Aβ40 and Aβ42, composed of 40 and 42 residues, respectively, are the major Aβ species in human brain. Aβ42 aggregates much faster than Aβ40 but the mechanism of such difference in aggregation propensity is poorly understood. Using NMR spin relaxation, we have shown that Aβ40 and Read More

We construct nanotubes using native protein structures and their native associations from structural databases. The construction is based on a shape-guided symmetric self-assembly concept. Our strategy involves fusing judiciouslyselected oligomerization domains via peptide linkers. Linkers are inherently flexible, hence their choice is critical: they should position the domains in three-dimensional space in the desired orientati Read More

Proteins are dynamic molecules that often undergo conformational changes while performing their specific functions, such as target recognition, ligand binding and catalysis. NMR spectroscopy is uniquely suited to study protein dynamics, because site-specific information can be obtained for motions that span a broad range of time scales. The information obtained from NMR dynamics experiments has provided insights into s Read More

Protein side chain dynamics is associated with protein stability, folding, and intermolecular interactions. Detailed dynamics information is crucial for the understanding of protein function and biochemical and biophysical properties, which can be obtained using NMR relaxation techniques. In this review, 13C relaxation of methine, methylene and methyl groups with and without 1H decoupling are described briefly for a better unde Read More

A new galactose-specific lectin, named BBL, was purified from seeds of Bauhinia bauhinioides by precipitation with ammonium sulfate, followed by two steps of ion exchange chromatography. BBL haemagglutinated rabbit erythrocytes (native and treated with proteolytic enzymes) showing stability even after exposure to 60 °C for one hour. The lectin haemagglutinating activity was optimum between pH 8.0 and 9.0 and inhi Read More

Neuropeptide FF (NPFF) belongs to an opioid-modulating peptide family. NPFF has been reported to play important roles in the control of pain and analgesia through interactions with the opioid system. However, very few studies examined the effect of supraspinal NPFF system on analgesia induced by opiates administered at the peripheral level. In the present study, intracerebroventricular (i.c.v.) injection of NPFF (1, 3 and 1 Read More

Water-soluble, biological-compatible, and excellent fluorescent CdSe/CdS quantum dots (QDs) with L-cysteine as capping agent were synthesized in aqueous medium. Fluorescence (FL) spectra, absorption spectra, and transmission electron microscopy (TEM) were employed to investigate the quality of the products. The interactions between QDs and bovine serum albumin (BSA) were studied by absorption and FL titration expe Read More

Allergic reactions to hymenoptera stings are one of the major reasons for IgE-mediated anaphylaxis. However, proper diagnosis using venom extracts is severely affected by molecular cross-reactivity. In this study recombinant honeybee venom major allergen phospholipase A2 (Api m 1) was produced for the first time in insect cells. Using baculovirus infection of different insect cell lines allergen versions providing a varyin Read More

The advent of sugar-immobilized gold nano-particles (SGNPs), lipid-based nanoparticles, nanochromatography and nano-electrophoresis has revolutionized the methodology for proteins purification and proteomic research. This review provides an overview on the effective method developed for fast purification of proteins from extracts using SGNPs. In addition, the current application of microfluidic systems for anal Read More