Protein and Peptide Letters - Volume 14, Issue 4, 2007

The interaction of Cu(II) ion with small peptides has been an interesting subject to clarify the role of copper in detail. As various Cu(II)-oligopeptide complexes can also be good models for the active centers of metalloenzymes, complexes of tripeptide and tetrapeptides are frequently investigated instead of the complexes of large peptides. The histidine side-chains of various metalloproteins frequently take part in the c Read More

Jasmonates play a critical role in plant defense against pathogens through regulation of the expression of defense- related genes.To study the role of jasmonic acid (JA) in the rice self-defense mechanism, a proteomic approach was applied. When 3-week-old rice cv. Java 14 was treated with 100 μM JA for 3 days, numerous necrotic brown spots were observed on the leaf blade.Three-week-old rice was treated with JA and proteins Read More

We tested the ability of Taq DNA polymerase (Taq) to amplify long DNA fragments and showed that, if the conditions were set properly, Taq could successfully perform the “long PCR” up to 24 kb. The conditions include: (1) longer primers, (2) a 2-step cycling, and (3) a “long buffer.” We propose that the most important requirements are the survival rate of Taq at high temperatures and that of the primers against the 5' to 3' exon Read More

Blomia tropicalis allergens are the most important mite allergens in tropical regions. Most of them only have 30-40% sequence identity with their Dermatophagoides counterparts and they share low IgE cross reactivity and exhibit different immunobiology. Unlike the pyroglyphid counterparts, Blo t 5 is the major allergen whereas Blo t 1 only has modest allergenicity.

Although the tertiary structures of mitochondrial cytochromes c (cyts c) seem to be remarkably similar, there are variations in their amino acid sequences, stability and functional properties. GdnHCl-induced unfolding experiments on engineered yeast and horse cyt c were carried out with the aim to to clarify, at molecular level, some aspects concerning the stability of this class of proteins. The results obtained are discusse Read More

This study indicated that the N-terminus was dispensable for FtsY GTPase activity, and that the N-domain plays an essential role in the GTPase activity of the NG domain. In addition, the S.scoelicolor FtsY was able to restore function in an E. coli mutant. However, its NG domain was unable to play any roles.

We show that α-synuclein could assist the molecular activity of a ketoprofen-(R/S) nonspecific esterase from Archaeglobus Fulgidus. Specifically, several synthetic peptides from α-synuclein, each having random coil conformation in far-UV spectra, could protect the enzyme activity against stress conditions such as heat and organic solvents.

Conformational properties of two potentially β-turn forming peptides were determined using a strategy which combines MD simulations, IR and VCD spectroscopy and quantum chemical calculations. This strategy could be a useful alternative for solution conformational analysis of short flexible peptides and could help to identify VCD features which are as yet unknown.

Background: The molecular regulation of MAPKs and apoptosis was investigated in a model of hypoxiatolerance. Survival of neurons in Chrysemys picta bellii, an anoxia-tolerant turtle, involves a reduction in energy metabolism. The biochemical/physiological mechanisms of anoxia tolerance have been examined at the level of ion transport and ATP turnover. However, changes in the phosphorylation state of key enzymes and Read More

Background: Pursuant to establishing the proteomic distribution of MAPKERK/MAPKp38 in the brain in a model of hypoxia-tolerance [Haddad, Protein Pept Lett, In press, 2007], I therein exclusively report the differential expression of MAPKJNK and related upstream and downstream kinases in various organs of the anoxia-tolerant turtle. Despite the fact that the aforementioned mechanisms involved dual expression of MAPKE Read More

Di/oligomerization of G-protein coupled receptors (GPCRs) is well established, however very little is known regarding the interaction details. Current paper presents results of molecular dynamics simulations of theoretical model of rhodopsin tetramer with transducine (Gt) in lipid bilayer. Ligand-protein and receptor-receptor interactions have been proposed.

Improperly folded metal cofactor-containing proteins (e.g., copper chaperone for superoxide dismutase, CCS) are believed to play a key role in several protein-misfolding diseases (e.g., Alzheimer's disease or Amyotrophic Lateral Sclerosis) because under regular physiological conditions, metallochaperones activate or stabilize the native conformation of important metalloproteins (e.g., superoxide dismutase) in certain cell Read More

Snake venoms hydrolyze several phosphorylated substrates. However, not is clearly understood which enzyme( s) is (are) involved in these process. Here, we propose the existence of an independent ADPase activity. In addition, we studied the reactions mechanism of nucleotide hydrolysis. This system resembles membrane ecto-nucleotidases and acts with a multi enzymatic complex transforming ATP in adenosine without the a Read More

A new member of archaeal DNA polymerase from Pyrococcus furiosus was crystallized. Diffraction data to 3.1 Å of the selenomethionine-derivatized crystal were collected, and preliminary crystallographic study has been completed. The crystal belongs to the space group C2 with unit cell parameters of a = 93.2 Å, b = 124.9 Å, c = 87.7 Å, α = 90 , β = 109.7® , and γ = 90 . Assuming the presence of one molecule in th Read More

PD-L1 is a highly glycosylated type 1 ribosome inactivating protein, from Phytolacca dioica leaves, with the peculiarity to act also as a DNase. PD-L1 has been successfully crystallized using vapour diffusion and seeding techniques. Crystals belong to the monoclinic C2 space group, with unit cell dimensions a=161.01, b=34.73, c=120.63 Å, β=127.99 . Two molecules are present in the asymmetric unit. Phase determination has be Read More