Protein and Peptide Letters - Volume 21, Issue 6, 2014

Cellular protein degradation systems are necessary to avoid the accumulation of misfolded or damaged proteins. Deficiency in these systems might cause to partial degradation of misfolded proteins and generation of amyloidogenic fragments. Protein misfolding is believed to be the primary cause of neurodegenerative disorders such as Alzheimer’s disease (AD). In this study, we investigate effect of two anionic peptide fragm Read More

Energy homeostasis is regulated by endocrine factors. The concentration of relaxin-3 in serum is related to body mass index. However, relaxin-3 is found only in the brain and testis. In this study, we examined the expression of relaxin- 3 in adipose tissue and its effects on adipogenesis. The expression of relaxin-3 was determined using RT-PCR, a relaxin- 3 C-peptide-specific radioimmunoassay, specifically in the stromal-vasc Read More

Azoreductase enzymes present in many microorganisms exhibit the ability to reduce azo dyes, an abundant industrial pollutant, to produce carcinogenic metabolites that threaten human health. All biochemically-characterized azoreductases, around 30 to date, have been isolated from aerobic bacteria, except for AzoC, the azoreductase of Clostridium perfringens, which is from a strictly anaerobic bacterium. AzoC is a r Read More

The enzymatic activity of leucine aminopeptidase (EC 3.4.11.1) from the intestinal tract of sugarcane giant borer (Telchin licus licus) was assayed by using a simple and sensitive spectrophotometric assay that uses L-leucyl-2- naphthylamide as substrate. In this assay, L-leucyl-2-naphthylamide is hydrolyzed to produce 2-naphthylamine and Lleucine. The product 2-naphthylamine reacts with Fast Black K and can be monitored usin Read More

Antagonists of AT1 receptor are interesting substances to develop drugs that can be used for the treatment of hypertension and other diseases that affect the cardiovascular system. This study investigates the main interactions between various AT1 antagonists and the biological target by applying fragment-based drug design (Hologram QSAR - HQSAR). The proposed HQSAR model yielded significant correlation coefficients Read More

TD1, a peptide chaperone consisting of the sequence ACSSSPHKHCG, has been shown to facilitate transdermal delivery for protein molecules via either co-administration or the fusion approach. We previously reported that a single TD1 motif, fused to the N-terminus of human epidermal growth factor (hEGF) can significantly enhance the transdermal efficiency of the recombinant EGF protein. In an effort to further increas Read More

Due to the vital role in many cell regulatory processes, such as cell cycle control, survival and apoptosis, as well as growth and neurotransmitter signaling, Src homology 2 (SH2) domain-containing phosphatase 2(Shp2) has attracted considerable attention for developing drugs to treat cancers. In this study, by means of the powerful “core hopping” technique, a novel class of inhibitors was discovered based on the comp Read More

E. coli small heat shock proteins IbpA and IbpB (inclusion body binding proteins A and B) are known to act as holding chaperones on denaturing, aggregate-prone proteins. But, there is no clear understanding about which of the IbpA and IbpB has more holdase activity and how the holdase activity of one was influenced by the presence of the other. This study was conducted to resolve the questions, using some uncommon p Read More

Fatty acid-binding proteins (FABPs) are extensively expressed in animals, involved in the metabolism of fatty acids. FABPs share a much conserved secondary structure though they have 20% ~ 70% identities at the amino acid level. In addition to the role in lipid metabolism, FABPs are closely associated with cytokine production in immune cells and tumor growth and angiogenesis. Increasing studies are broadening our underst Read More

Iron superoxide dismutase (Fe-SOD) can eliminate superoxide anion radicals and is widely used in pharmaceuticals, cosmetics and foodstuff. It’s significant to determine the factors that influence Fe-SOD thermostability. Previous studies have focused on the relationship between the structural parameters and thermostability of Fe-SOD while the contribution of water molecules was overlooked. In this study, we examined the rel Read More

Insulin has many actions within cells many of which are dependent on the cell type. For example, insulin stimulates glucose uptake in adipose tissue and skeletal muscle but not in liver. In liver glucose influx will increase as insulin stimulates the phosphorylation of glucose and eventual storage in the form of glycogen. Insulin also increases glucose oxidation, decreases glucose production, decreases lipolysis, increases protein synt Read More

About twenty years ago, the search for a peptide mimetic of the crucial 928-amino acid human retinoblastoma tumor suppressor protein (RB) has led to the identification of a potential active site in RB spanning 6 amino acids. Subsequent studies revealed that this hexapeptide needs to be coupled to a cellular internalization sequence in order to be biologically active. The prototype molecule resulting therefrom has been the Read More

Cyclic oligopeptides have been introduced into pharmacological use for uses as diverse as selective release of the clotting factor VIII (von Willebrandt factor) by vasopressin, immune modulation by cyclosporin and antibacterial activity by vancomycin. Even now, 60 years after the first isolation of vancomycin (3,4) and the sequencing of oxytocin (48) these compounds have not lost their important role in clinical use. Wit Read More

DNA sequencing has revealed that Gluconobacter oxydans may contain an incomplete phosphoenolpyruvate: carbohydrate phosphotransferase system (PTS), but the function of individual members of the system remains unknown. Here we demonstrated that the predicted histidine protein HPr, an essential component of PTS, can be phosphorylated by a predicted HPr kinase in G. oxydans, where Ser54 in HPr is the site resp Read More