HIV Capsid and Protease,New Targets of Melittin

International Journal of Peptide Research and Therapeutics - Melittin is a 26 amino acid amphipathic peptide, the main part of a bee venom. It has been confirmed that melittin can act against a...     

Post-infarct sleep disruption and its relation to cardiac remodeling in a rat model of myocardial infarction

Sleep disruption after myocardial infarction (MI) by affecting ubiquitin–proteasome system (UPS) is thought to contribute to myocardial remodeling and progressive worsening of cardiac function. The aim of current study was to test the hypothesis about the increased risk of developing heart failure due to experience of sleep restriction (SR) after MI. Male Wistar rats (n = 40) were randomly assigned to four experimental groups: (1) Sham, (2) MI, (3) MI and SR (MI + SR) (4) Sham and SR (Sham + SR). MI was induced by permanent ligation of left anterior descending coronary artery. Twenty-four hours after surgery, animals were subjected to chronic SR paradigm. Blood sampling was performed at days 1, 8 and 21 after MI for determination of serum levels of creatine kinase-MB (CK-MB), corticosterone, malondialdehyde (MDA) and nitric oxide (NO). Finally, at 21?days after MI, echocardiographic parameters and expression of MuRF1, MaFBx, A20, eNOS, iNOS and NF-kB in the heart were evaluated. We used H&;E staining to detect myocardial hypertrophy. We found out that post infarct SR increased corticosterone levels. Our results highlighted deteriorating effects of post-MI SR on NO production, oxidative stress, and echocardiographic indexes (p < 0.05). Moreover, its detrimental effects on myocardial damage were confirmed by overexpression of MuRF1, MaFBx, iNOS and NF-kB (p < 0.001) in left ventricle and downregulation of A20 and eNOS (p < 0.05). Furthermore, histological examination revealed that experience of SR after MI increased myocardial diameter as compared to Sham subjects (p < 0.05). Our data suggest that SR after MI leads to an enlargement of the heart within 21?days, marked by an increase in oxidative stress and NO production as well as an imbalance in UPS that ultimately results in cardiac dysfunction and heart failure.     

Preparation of FMD type A87/IRN inactivated vaccine by gamma irradiation and the immune response on guinea pig

FMD is one of the most economically damaging diseases that affect livestock animals. In this study FMD Virus type A87/IRN was multiplied on BHK21 cells. The virus was titrated by TCID50 method, it was 10^7.5/ml. The FMD virus samples were inactivated by gamma ray from 60Co source at −20°C. Safety test was done by IBRS2 monolayer cell culture method, also antigenicity of irradiated and un-irradiated virus samples were studied by Complement Fixation Test. The Dose/Survival curve for irradiated FMD Virus was drawn, the optimum dose range for inactivation of FMDV type A87/IRN and unaltered antigenicity was obtained 40–44 kGy. The inactivated virus samples by irradiation and ethyleneimine (EI) were formulated respectively as vaccine with Al(OH)3 gel and other substances. The vaccines were inoculated to Guinea pigs and the results of Serum Neutralization Test for the normal vaccine and radio-vaccine showed protective titer after 8 months. The potency test of the inactivated vaccines was done, PD50 Value of the vaccines were calculated 7.06 and 5.6 for inactivated vaccine by EI and gamma irradiation respectively.     

Whole-Genome Resequencing Reveals Extensive Natural Variation in the Model Green Alga Chlamydomonas reinhardtii

We performed whole-genome resequencing of 12 field isolates and eight commonly studied laboratory strains of the model organism Chlamydomonas reinhardtii to characterize genomic diversity and provide a resource for studies of natural variation. Our data support previous observations that Chlamydomonas is among the most diverse eukaryotic species. Nucleotide diversity is ∼3% and is geographically structured in North America with some evidence of admixture among sampling locales. Examination of predicted loss-of-function mutations in field isolates indicates conservation of genes associated with core cellular functions, while genes in large gene families and poorly characterized genes show a greater incidence of major effect mutations. De novo assembly of unmapped reads recovered genes in the field isolates that are absent from the CC-503 assembly. The laboratory reference strains show a genomic pattern of polymorphism consistent with their origin as the recombinant progeny of a diploid zygospore. Large duplications or amplifications are a prominent feature of laboratory strains and appear to have originated under laboratory culture. Extensive natural variation offers a new source of genetic diversity for studies of Chlamydomonas, including naturally occurring alleles that may prove useful in studies of gene function and the dissection of quantitative genetic traits.     

Role of the non‐hypervariable FR3 D‐E loop in single‐domain antibody recognition of haptens and carbohydrates

Single‐domain antibodies (sdAbs), the variable domains of camelid heavy chain‐only antibodies, are generally thought to poorly recognize nonproteinaceous small molecules and carbohydrates in comparison with conventional antibodies. However, the structures of anti‐methotrexate, anti‐triclocarban and anti‐cortisol sdAbs revealed unexpected contributions of the non‐hypervariable “CDR4” loop, formed between β‐strands D and E of framework region 3, in binding. Here, we investigated the potential role of CDR4 in sdAb binding to a hapten, 15‐acetyl‐deoxynivalenol (15‐AcDON), and to carbohydrates. We constructed and panned a phage‐displayed library in which CDR4 of the 15‐AcDON‐specific sdAb, NAT‐267, was extended and randomized. From this library, we identified one sdAb, MA‐232, bearing a 14‐residue insertion in CDR4 and showing improved binding to 15‐AcDON by ELISA and surface plasmon resonance. On the basis of these results, we constructed a second set of phage‐displayed libraries in which the CDR4 and other regions of three hapten‐ or carbohydrate‐binding sdAbs were diversified. With the goal of identifying sdAbs with novel glycan‐binding specificities, we panned the library against four tumor‐associated carbohydrate antigens but were unable to enrich binding phages. Thus, we conclude that while CDR4 may play a role in binding of some rare hapten‐specific sdAbs, diversifying this region through molecular engineering is probably not a general solution to sdAb carbohydrate recognition in the absence of a paired V_L domain.     

Development of a Bacterial Surface Display of Hexahistidine Peptide Using CS3 Pili for Bioaccumulation of Heavy Metals

A novel cell surface display system for metal uptake was developed using CS3 pili of enterotoxigenic Escherichia coli, which is a suitable system for display of heterologous peptides. The recombinant bacteria producing the hybrid pili containing the hexahistidine peptide accumulated high concentrations of Cd²⁺ and Ni²⁺ at 656.2 and 276.5 nmol per mg dry weight of bacterial cell, respectively. The recombinant bacteria may be useful in water and waste water treatment.