UK PubMed Central (United Kingdom)

The gene encoding N epsilon-(indole-3-acetyl)-L-lysine synthetase, iaaL, from Pseudomonas savastanoi was localized within a 4.25-kilobase EcoRI fragment derived from pIAA1 of oleander strain EW 2009....Full Text Available

UK PubMed Central (United Kingdom)

Patent ductus arteriosus (PDA) affects approximately 31% of infants whose birth weight is between 501 and 1500 g. The ductus arteriosus is a blood vessel that allows blood to bypass the pulmonary vasculature...Full Text Available

UK PubMed Central (United Kingdom)

Progressive obstructive lung disease is a characteristic component of cystic fibrosis (CF). It is the pulmonary manifestations, including obstruction and endobronchial infection, which directly contribute...Full Text Available

International Nuclear Information System (INIS)

Methanosarcina thermophila, a nonmarine methanogenic archaebacterium, can grow in a range of saline concentrations. At less than 0.4 M NaCl, Ms. thermophila accumulated glutamate in response to increasing osmotic stress. At greater than 0.4 M NaCl, this organism synthesized a modified #beta#-amino acid that was identified as N"v"a"r"-"e"p"s"i"l"o"n-acetyl-#beta#-lysine by NMR spectroscopy and ion-exchange HPLC. This #beta#-amino acid derivative accumulated to high intracellular concentrations (up to 0.6 M) in Ms. thermophila and in another methanogen examined - Methanogenium cariaci, a marine species. The compound has features that are characteristic of a compatible solute: it is neutrally charged at physiological pH and it is highly soluble. When the cells were grown in the presence of exogenous glycine betaine, a physiological pH and it is highly soluble. When the cells were grown in the presence of exogenous glycine betaine, a physiological compatible solute, ...

Science.gov (United States)

There are about fifty SET domain protein methyltransferases (PMTs) in the human genome, that transfer a methyl group from S-adenosyl-L-methionine (SAM) to substrate lysines on histone tails or other peptides. A number of structures in complex with cofactor, substrate, or inhibitors revealed the mechanisms of substrate recognition, methylation state specificity, and chemical inhibition. Based on these structures, we review the structural chemistry of SET domain PMTs, and propose general concepts towards the development of selective inhibitors.

UK PubMed Central (United Kingdom)

Low cytotoxicity and high gene transfection efficiency are critical issues in designing current non-viral gene delivery vectors. The purpose of the present work was to synthesize the novel biodegradable...Full Text Available

Science.gov (United States)

Tau is a microtubule-associated protein that promotes microtubule assembly and stability. In Alzheimer's disease and related tauopathies, tau fibrillizes and aggregates into neurofibrillary tangles. Recently, oleocanthal isolated from extra virgin olive oil was found to display non-steroidal anti-inflammatory activity similar to ibuprofen. Since our unpublished data indicates an inhibitory effect of oleocanthal on A? fibrillization, we reasoned that it might inhibit tau fibrillization as well. Herein we demonstrate that oleocanthal abrogates fibrillization of tau by locking tau into the naturally unfolded state. Using PHF6 consisting of the amino acid residues VQIVYK, a hexapeptide within the third repeat of tau that is essential for fibrillization, we show that oleocanthal forms an adduct with the lysine via initial Schiff base formation. Structure and function studies demonstrate that the two aldehyde groups of oleocanthal are required for the inhibitory ...

International Nuclear Information System (INIS)

Nop25 is a putative RNA binding nucleolar protein associated with rRNA transcription. The present study was undertaken to determine the mechanism of Nop25 localization in the nucleolus. Deletion experiments of Nop25 amino acid sequence showed Nop25 to contain a nuclear targeting sequence in the N-terminal and a nucleolar targeting sequence in the C-terminal. By expressing derivative peptides from the C-terminal as GFP-fusion proteins in the cells, a lysine and arginine residue-enriched peptide (KRKHPRRAQDSTKKPPSATRTSKTQRRRR) allowed a GFP-fusion protein to be transported and fully retained in the nucleolus. When the peptide was fused with cMyc epitope and expressed in the cells, a cMyc epitope was then detected in the nucleolus. Nop25 did not localize in the nucleolus by deletion of the peptide from Nop25. Furthermore, deletion of a subdomain (KRKHPRRAQ) in the peptide or amino acid substitution of lysine and arginine residues in the subdomain ...

British Library Electronic Table of Contents (United Kingdom)

Peptide sequences such as lysine-arginine-serine-arginine (KRSR) selectively bind transmembrane proteoglycans (e.g. heparin sulfate) of osteoblasts (bone-forming cells) and are, therefore, actively being investigated for orthopedic applications. Further, nanophase materials (or materials with grain or particle sizes less than 100 nm) are promising new materials that promote new bone growth more than compared to conventional (that is, micron grain or particle size) materials. To combine the above two promising approaches for improving orthopedic implants, the objective of this in vitro study was to functionalize titanium (Ti) surfaces (both nanophase and conventional) with KRSR peptides and study their osteoblast cell adhesive properties. Materials were characterized by X-ray photoelectron ...

Energy Technology Data Exchange (ETDEWEB)

ATR-X (alpha-thalassemia/mental retardation, X-linked) syndrome is a human congenital disorder that causes severe intellectual disabilities. Mutations in the ATRX gene, which encodes an ATP-dependent chromatin-remodeler, are responsible for the syndrome. Approximately 50% of the missense mutations in affected persons are clustered in a cysteine-rich domain termed ADD (ATRX-DNMT3-DNMT3L, ADD{sub ATRX}), whose function has remained elusive. Here we identify ADD{sub ATRX} as a previously unknown histone H3-binding module, whose binding is promoted by lysine 9 trimethylation (H3K9me3) but inhibited by lysine 4 trimethylation (H3K4me3). The cocrystal structure of ADD{sub ATRX} bound to H3{sub 1-15}K9me3 peptide reveals an atypical composite H3K9me3-binding pocket, which is distinct from the conventional trimethyllysine-binding aromatic cage. Notably, H3K9me3-pocket mutants and ATR-X syndrome mutants are defective in both H3K9me3 binding and ...

Energy Technology Data Exchange (ETDEWEB)

The /sup 31/P NMR method was first applied to characterize in vivo phosphorylation of H1 and H5 in calf thymus and chicken erythrocytes as well as in vitro phosphorylation of H1 and H5 by cAMP-dependent protein kinase. The amino acid residues phosphorylated in vivo in the histones were exclusively serine residues, and the mole fraction of phosphoserine was estimated to be 0.34 and 0.27 per molecule of calf thymus H1 and chicken erythrocyte H5, respectively. Interestingly, chicken erythrocyte H1 was not phosphorylated in vivo. Three H1 subtypes from calf thymus H1 varied in the /sup 31/P NMR spectra, and the bisected fragments of calf thymus H1 and chicken erythrocyte H5 exhibited characteristic spectral patterns, indicating that there are considerable diversities of the degree of phosphorylation and phosphorylation sites in very-lysine-rich histones. Furthermore, it was found that the microenvironment of phosphoserine residues phosphorylated in vivo in calf thymus ...

Science.gov (United States)

Cell-penetrating peptides (CPPs) are useful tools for the delivery of hydrophilic bioactive molecules, such as peptides, proteins, and oligonucleotides, across the cell membrane. To realize the delivery of therapeutic macromolecules by CPPs, the CPPs are required to show resistance to protease and no cytotoxicity. In order to produce potent non-toxic and protease-resistant CPPs with high cellular uptake, we designed an amphipathic helix peptide using ?-aminoisobutyric acid (Aib, U) and named it MAP(Aib). In the MAP(Aib) molecule, five Aib residues are aligned on the hydrophobic face of the helix and five lysine (K) residues are aligned on the hydrophilic face. MAP(Aib) showed potent resistance to trypsin and pronase compared with MAP, an amphipathic helix peptide formed by usual amino acids. Fluorescein-labeled MAP(Aib) efficiently traversed the A549 cell membrane, diffusing into the cytoplasm and slightly into the nucleus without exerting any cytotoxicity. In ...

Energy Technology Data Exchange (ETDEWEB)

A preliminary chemical characterization is presented of phosphate-free aminolipids isolation from Chlorobium limicola f. thiosulfatophilum. The lipid contains no phosphorus, glycerol, sugar, ornithine, or lysine. Ultraviolet absorption and fluorescence spectra indicate that the amino moiety of the lipid is an aromatic heterocyclic compound. Infrared spectra indicate that the lipid is a secondary or tertiary amide, and gas chromatograhic analysis of the hydrolyzed lipid shows that for each 1100 g of lipid, 1 mol of myristic acid (C/sub 14:0/) is linked in an amide bond. Acid hydrolysis of the lipid yields two fluorescent substances, A (ninhydrine positive) and B (negative), in addition to myristic acid. Proton nuclear magnetic resonance (NMR) studies indicate that substance A contains a butyl groups attached to a conjugated ring carbon, two equivalent ethyl groups attached to one or two nitrogen atoms, and two downfield protons (8.4 ppm), perhaps attached to a ring ...

Energy Technology Data Exchange (ETDEWEB)

Heterochromatin constitutes a significant portion of the genome in higher eukaryotes; approximately 30% in Drosophila and human. Heterochromatin contains a high repeat DNA content and a low density of protein-encoding genes. In contrast, euchromatin is composed mostly of unique sequences and contains the majority of single-copy genes. Genetic and cytological studies demonstrated that heterochromatin exhibits regulatory roles in chromosome organization, centromere function and telomere protection. As an epigenetically regulated structure, heterochromatin formation is not defined by any DNA sequence consensus. Heterochromatin is characterized by its association with nucleosomes containing methylated-lysine 9 of histone H3 (H3K9me), heterochromatin protein 1 (HP1) that binds H3K9me, and Su(var)3-9, which methylates H3K9 and binds HP1. Heterochromatin formation and functions are influenced by HP1, Su(var)3-9, and the RNA interference (RNAi) pathway. My thesis project ...