Protein and Peptide Letters - Volume 20, Issue 5, 2013

Antimicrobial peptides (AMPs) constitute an important alternative in the search for new treatments against pathogens. We analyzed the sequence variability in cytokine and chemokine proteins to investigate whether these molecules contain a sequence useful in the development of new AMPs. Cluster analysis allowed the identification of tracts, grouped in five categories showing structure and sequence homology. The structure Read More

Wrightia tinctoria globulin (WTG), one of the major seed storage proteins, was isolated for the first time from seeds of the medicinal plant. WTG was extracted and purified to homogeneity in two steps using anion-exchange and size-exclusion chromatographies. On an SDS-PAGE gel under non-reducing conditions, a major band of ˜56 kDa was observed; under reducing conditions, however, two major polypeptides, one with mol Read More

The effect of a cosolvent on the structure and stability of a protein depends upon the nature of preferential protein- water, protein-cosolvent or cosolvent-water interactions. The preferential interaction parameters of glycerol, sorbitol and sucrose with β-globulin (from Sesamum indicum L. seeds) were evaluated and the results showed the exclusion of cosolvents and preferential hydration of the protein. Data from fluoresce Read More

A fusion gene isolated from a microbial metagenome encodes a N-terminal endo-1,4-β-mannanase and a Cterminal 1,3-1,4-β-glucanase,. The full-length gene and the individual N- and C-domains were separately cloned and expressed in E coli. The purified whole enzyme hydrolyzed glucomannan, galactomannan, and β-glucan with Km and kcat values 2.2, 2.6, 3.6 mg/ml, and 302, 130, 337 min -1 , respectively. The h Read More

Carboxyl terminus of Hsp70 interacting protein (CHIP) is a dimeric co-chaperone involved in providing an appropriate balance between the synthesis and degradation of proteins, which is essential for normal cellular growth and function. Previous work has shown that CHIP, but not its isolated domains, has chaperone activity that is enhanced by heat. In this work, we investigate how heat and urea affect the stability of i Read More

Cluster of Orthologous Groups (COG) 1092 contains two distinct types of methylation enzyme from Escherichia coli, YccW and YcbY. YccW is a 5-methylcytosine methyltransferase (m5C MTase) responsible for m5C 1962 in 23S rRNA, whereas YcbY is a dimethyltransferase, of which N- and C-terminal domains are responsible for N2- methylguanosine (m2G) 2445 and 7-methylguanosine (m7G) 2069 in 23S rRNA, respectively. H Read More

Cytidine deaminase (CDA), is one of the enzymes involved in the pyrimidine salvage pathways, which catalyzes the formation of uridine and deoxyuridine by the hydrolytic deamination of cytidine and deoxycytidine, respectively. Human CDA is a tetrameric enzyme of identical 15 kDa subunits, each containing an essential zinc atom in the active site. The substrate binds to each active site independently and the cooper Read More

The presence of senile plaques in the brain is one of the pathological hallmarks of Alzheimer’s disease (AD). The biogenesis and clearance of the amyloid β peptide (Aβ), the main component of the lesions, lie at the center of the pathogenesis of AD. In sporadic AD, the increase of Aβ levels seems to be indicative of failure of clearance mechanisms. We previously showed that the clearance of the wild type Aβ40 peptide by va Read More

Calreticulin is a soluble endoplasmic reticulum chaperone, which has a relatively low melting point due to its remarkable structure with a relatively high content of flexible structural elements. Using far ultraviolet circular dichroism (CD) spectroscopy and a fluorescent dye binding thermal shift assay, we have investigated the chemical and thermal stability of calreticulin. When the chemical stability of calreticulin was assessed, a Read More

Expansion of polyglutamine (polyQ) sequence in some proteins leads to their aggregation, which is responsible for neurodegenerative diseases like Huntington's disease, ataxia etc. A flanking domain is usually fused at the N-terminal to polyQ in these proteins. On linking the flanking residues to polyQ, they accelerate aggregation of the proteins, which initiates from the flanking residues. In this report the inherent propensity of th Read More

EFhd2 is a novel protein conserved from C. elegans to H. sapiens. This novel protein was originally identified in cells of the immune and central nervous systems. However, it is most abundant in the central nervous system, where it has been found associated with pathological forms of the microtubule-associated protein tau. The physiological or pathological roles of EFhd2 are poorly understood. In this study, a functional an Read More

BALB/c mice were immunized by highly immunogenic recombinant proteins containing amino acid sequence of integrin antagonist AP25. Antibody against AP25 was prepared and purified by affinity chromatography. An indirect enzyme-linked immunosorbent assay for qualitative analysis of AP25 in rat plasma samples was successfully established. The assay was successfully applied to determine the pharmacokinetic parame Read More

A novel manganese peroxidase (MnP) isolated from solid state culture of Trametes versicolor IBL-04 was immobilized using xerogel matrix composed of trimethoxysilane (TMOS) and propyltetramethoxysilane (PTMS). FTIR spectroscopy confirmed the successful entrapment of MnP into the xerogel matrix. An immobilization efficiency of 92.2% was achieved with a purified active fraction containing 2 mg/mL MnP. After 24 Read More

Regular consumption of natural antioxidants reduces the risk of developing diseases. Aloin is one of the main active phenolic components of Aloe vera. The main disadvantage of aloin is its concentration limit of use that causes cell damage. One of the aims of this study was to investigate the antioxidant activity of aloin in the presence and absence of camel β-casein (β-CN) and its peptide fractions. The mixture of aloin,β-CN an Read More