Protein and Peptide Letters - Volume 12, Issue 4, 2005

Significant efforts are put into the design of large-scale purification processes of proteins due to great demands regarding cost efficiency and safety. In order to design an effective purification scheme the unit operations need to be reduced to a minimum. In this review we are discussing proteinaceous ligands as well as small synthetic mimics for use in affinity chromatography for large-scale applications. Different advanta Read More

The carboxyl terminus domain of Schizosaccharomyces pombe dicer (yDicerC) was expressed in Escherichia coli as an MBP-fusion protein (MBP-yDicerC). When the E. coli strain was cultured and induced at 25°C, the MBPyDicerC was partly expressed in the soluble fraction. It was then purified by two step affinity chromatography with amylose resin and Ni-NTA His.Bind® resin. The purified MBP-yDicerC showed double-st Read More

The nonstructural protein 3 (NS3) of hepatitis C virus contains a protease domain at its amino terminus and RNA helicase domain at its carboxyl terminus. To identify optimal NS3 protein for developing screening assays, we expressed full-length NS3 protease/helicase and helicase domains from both HCV type 1a (H77 strain) and 1b (Con1 strain), using either E. coli or baculovirus expression systems. Our studies showed that Read More

[Tic4]EM1 and [Tic4]EM2, new endomorphins (EMs) analogues, caused relaxation of rat aorta rings precontracted with phenylphrine in a concentration-dependent manner and were 240- to 370-fold more potent than EMs. This effect was inhibited by endothelium removal or by incubation with NO synthase inhibitor L-NNA or opioid receptor antagonist naloxone. The results demonstrate that [Tic4]EMs have NO- a Read More

After investigating two anion-exchange resins, the purification factor and activity yields of P450 BM-3 were higher with Resource Q than with DEAE-Sepharose FF. Screening of HIC media showed that Source 15ISO was the most suitable for purification of P450 BM-3. An effective isolation and purification procedure of P450 BM-3 was developed and included three steps: 35%-70% saturation (NH4)2SO4 precipitation, Source 15IS Read More

An algorithm for automatic clustering of database protein sequences from Bothrops jararacussu venomous gland, according to sequence similarities of their domains, is described. The program was written in C and Perl languages. This algorithm compares a domain with each ORF protein sequence in the database. Each nucleotide FASTA sequence generates six ORFs. As a result, the user has a list containing all seq Read More

Information theory is used to analyze the character of signal peptide quantitatively, especially residents. On the basis of the above analysis, a method named simplified information-matrix has been developed to predict the cleavage sites of signal peptides. A comparison between the results of weight-matrix and simplified information-matrix is presented.

Complete analyses of NMR data of oxytocin (OT) and 4 analogues, ([o-MePhe2]OT, [mMe-Phe2]OT, [m- OMePhe2]OT and [p-MePhe2]OT), are given. The same conformational behavior in solution on one hand and large differences in biological activities on the other hand indicate that the compounds adopt a “biologically active conformation” at the stage of interaction with the receptor when the character of the substituen Read More

Adenoregulin is a 33 amino acid antibiotic peptide who belongs to dermaseptin family which is the first vertebrate family to show lethal effects against filamentous fungi, as well as a broad spectrum of pathogenic microorganisms. Synthetic adenoregulin gene was cloned in 2, 4 and 6 tandem repeats and subcloned in pET32a and pET22b vectors. Recombinant plasmids were transformed into E. coli BL21(DE3), Fusion p Read More

In this paper we describe a reductive amination procedure that can be employed in the preparation of a novel class of pseudopeptides in which a specific amide bond is replaced by a CH(Ar)NH group. The developed methodology, performed using NaBH3CN and TiCl4, is characterized by the formation of diastereomeric intermediates in a relative 1:1 ratio. It provides aryl aminomethin pseudopeptides in moderate but satisfact Read More

In this study, the effect of the scorpion a-like toxin BmK M1 was investigated on isolated DUM neurons from Locusta migratoria and compared with the effect on para/tipE voltage-gated Na+ channels (VGSC), cloned from Drosophila melanogaster. The two insects display different pharmacological properties regarding α-like toxins. Moreover, with the aid of the α-like toxin BmK M1 and 5 of its mutants, the importan Read More

Thermal inactivation and unfolding of the dimeric arginine kinase (AK) from sea cucumber Stichopus japonicus was investigated. The activation energy was calculated to be 388 kJ/mol. Based on the analysis of the denaturation course at 58°C, a model is suggested for the thermal unfolding of this dimeric AK. In addition, the effect of free Mg2+ and the potential biological significance on the thermal unfolding of dimeric AK is discussed.

Protease MCP-01 is similar to other cold-adapted enzymes in that it is a cold-adapted serine protease having high specific activity and low thermostability at low and moderate temperature. Its thermolability and self-autolysis has resulted in difficulties in its purification, preservation and research on its structure and function. The disaccharide trehalose is known to effectively stabilize proteins. Its prevention effect on the a Read More

The fact that loops assume important roles in molecular functions and biological recognition is well known. In this study the Propensity and the Relative entropy of amino-acids in loop structures connecting beta-strands are calculated. Results showed that Asn is the most frequently occurring amino-acid in loop regions connecting beta-strands, followed by Gly, Asp, Ser, and Thr. Results presented here can serve for modeling lo Read More

A novel hybrid genetic algorithm (GA)/radial basis function neural network (RBFNN) technique, which selects features from the protein sequences and trains the RBF neural network simultaneously, is proposed in this paper. Experimental results show that the proposed hybrid GA/RBFNN system outperforms the BLAST and the HMMer.

The N-terminal ankyrin repeat domain of the 2'-5'-linked oligoadenylate (2-5A)-dependent endoribonuclease, RNase L, has been crystallized by the hanging-drop vapor diffusion method in the presence of 2-5A. The crystals belong to an orthorhombic space group P212121 with cell dimensions of a = 63.11 Å, b = 73.03 Å, and c = 82.64 Å. There is one molecule per asymmetric unit. The crystals diffract to at least 2.1 Åresolution us Read More

The Zα domain (yabaZαE3L) of the E3L protein homologue from Yaba-like disease virus, a yatavirus, was cocrystallized with d(TCGCGCG)2 in the Z-conformation. The crystals belong to the P21212 space group, with unit-cell parameters a=51.20 Å, b=92.45 Å, c=48.02 Å, α=β= γ=90 . The diffraction data were collected up to a resolution of 2.2 Å. The structure of viral Za motif will provide an insight into how diverse Zα moti Read More