Protein and Peptide Letters - Volume 17, Issue 7, 2010

The cyclic peptide EGLNcΨ[CON((CH2)3NH)pYNleE(NHCH2CO)]L-NH2 (1) was designed and synthesized according to a native interaction partner of tyrosine phosphatase SHP-1. We introduced N-aminopropyl-phosphotyrosine to enable backbone-side chain cyclization with a glutamic acid derivative as counterpart for cyclization. Different approaches have been compared to find a strategy for the generation of backbone a Read More

A dimeric 34-kDa antifungal protein, designated as acafusin, was purified from Acacia confusa seeds using Q-Sepharose, DEAE-cellulose, Mono S and Superdex S75. It demonstrated antifungal activity toward Rhizoctonia solani with an IC50 of 28 μM. Acafusin inhibited the activity of HIV-1 reverse transcriptase mildly with an IC50 of 80 μM.

A 22.4-kDa dimeric hemagglutinin was isolated from tubers of Colocasia esculenta cv. ‘Small Taro’ by employing a purification protocol that involved ion exchange chromatography on Q-Sepharose, fast protein liquid chromatography (FPLC)-ion exchange chromatography on Mono Q, and FPLC-gel filtration on Superdex 75. The hemagglutinin was isolated from the fraction of the taro extract adsorbed on Q-Sepharose and s Read More

The crystal structure for the Deinococcus radiodurans Nudix protein DR_0079 was recently determined in the metal-free form at 1.9 Å resolution (2O5F). The protein adopts the fundamental fold common to the Nudix family of proteins, a large mixed β-sheet sandwiched between the α-helix of the “Nudix box” and a second α-helix. The protein's physical properties were further characterized by circular dichroism (CD) spectrosco Read More

Jasmonic acid (JA) and salicylic acid (SA) are signaling molecules that play key roles in the regulation of metabolic processes, reproduction, and defense against pathogens. The proteomics approach was used to identify proteins that are induced by JA and SA in the tomato cultivars Roma and Pant Bahr, which are susceptible and resistant to bacterial wilt, respectively. Threonine deaminase and leucine amino peptidase were up Read More

A novel class of L-lysine derivatives as aminopeptidase N (APN) inhibitors was designed and synthesized. Activity evaluation showed that compound C7 (IC50 = 9.6 ± 1.3 μM) and C20 (IC50 = 13.6 ± 1.9 μM) were equivalent to the positive control Bestatin (IC50 = 11.3 ± 1.6 μM).

Studies have shown that inverse proteins are relatively abundant. In this work, we investigate the proposition that the repeat patterns they share with protein sequences explain this phenomenon. Using a new artificial set of peptide sequences which also display these features and a random set, we show that the presence of repeats contributes to protein sequence similarity. Further analysis confirms that most inverse protein Read More

Multidrug-resistance-associated protein 6 (MRP6/ABCC6) is a protein belonging to the ABC transporter family which couple ATP hydrolysis with the transport of molecules across biological membranes. MRP6 topology presents three transmembrane domains and two nucleotide-binding domains (NBDs). The protein is structurally and functionally poorly characterized. Mutations in ABCC6 gene cause Pseudoxanthoma elasticum, a r Read More

Two-component systems (TCS) involving the His-Asp phosphotransfer are commonly utilized for signal transduction in prokaryotes in which the two essential components are a sensor histidine kinase (HK) receptor and a response regulator (RR). Despite great efforts in structural and functional characterization of signal perception mechanisms, the exact signaling mechanisms remain elusive for many TCSs. Mimicking the natural Read More

The in vitro insulin unfolding had been studied using the “equilibrium unfolding” method where protein is unfolded by reducing reagents in the presence of trace amounts of oxidants such as oxidized glutathione. Nine intermediates were captured in the unfolding process, named as P1A, P2A, P3A, P4A, P3B, P4B, P5B, P6B, and P7B, which were all either A chain derivatives or B chain derivatives. No intermediate with inter- Read More

Taking all the proteins of four virus genomes as samples, the segments of α-helix and β-strand in proteins of the four viruses were obtained. Linear regression analyses between the average polarities and the folding rates of peptide chains were performed for α-helices and β-strands respectively. The results indicated that the folding rates show significant positive linear correlation for α-helices and negative linear corr Read More

Bz(NO2)-Orn(Boc)-OCH2CN was synthesized as an amino acid component with effective and successful orthogonal protection for amino acylation of 5'-O-Pivaloyl nucleosides and preparation of substrates for model ribosome reactions. The synthesis was carried out using suitable combinations of the methods of peptide synthesis and modification of amino acids.

The transcription factor (TF) is a protein that binds DNA at specific site to help regulate the transcription from DNA to RNA. The mechanism of transcriptional regulatory can be much better understood if the category of transcription factors is known. We introduce a system which can automatically categorize transcription factors using their primary structures. A feature analysis strategy called “mRMR” (Minimum Redu Read More

Human histatins are histidine-rich, low molecular weight salivary proteins that contribute to the immune system of the oral cavity. In this work, nucleotide sequences of the HIS1 (coding for histatin 1) and HIS2 (coding for histatin 3) genes, homologous to the human ones, have been sequenced and analysed in five primates species including Great Ape, Hylobatidae and Cercopithecidae. In HIS1, the region correspondi Read More

Overactivity of platelet-derived growth factor (PDGF) has been linked to malignant cancers. High levels of PDGF result in the activation of its receptors (PDGFRs) and the over-proliferation of cells. Therefore, interfering with this signaling pathway in cancer cells could be significant for anti-cancer drug development. In a previous study, the sPDGFRα-Fc fusion protein expressed in static CHO-k1 cells showed an anti-proliferati Read More

It has been recently reported that thiol groups could play an important role in the protection of neuronal cells in Alzheimer's disease (AD), prion disease (CJD) and Parkinson's disease (PD). Also bucillamine, that is a pseudo dipeptide possessing a thiol group capable to form an internal disulfide bridge, has relevant scavenger properties used in therapy for the treatment of arthritis. Furthermore, many sulphur containing Read More