Correlation between Structure and Energetic Properties of Three Nitroaromatic Compounds: Bis(2,4-dinitrophenyl) Ether, Bis(2,4,6-trinitrophenyl) Ether, and Bis(2,4,6-trinitrophenyl) Thioether.

Decades after the initial discovery of bis(2,4,6-trinitrophenyl) ether derivatives, the first single-crystal X-ray structures for three members of this compound class can finally be shown and the analytical data could be completed. This group of molecules is an interesting example that illustrates why older predictive models for the sensitivity values of energetic materials like bond dissociation enthalpy and electrostatic potential sometimes give results that deviate significantly from the experimentally determined values. By applying newer models like Hirshfeld surface analysis and fingerprint plot analysis that utilize the crystal structure of an energetic material, the experimentally found trend of sensitivities could be understood and the older models could be brought into a proper perspective.

Evaluation of protein loading techniques and improved separation in OFFGEL isoelectric focusing.

2-DE proved to be a key technology in protein science since the two orthogonal separation dimensions are capable of protein isoform separation. Recently, Agilent introduced the OFFGEL 3100 fractionator for in solution IEF (off-gel) of proteins with the help of a 12- or 24-well frame. With this instrument also conventional focusing in IPG strips after passive in-tray rehydration can be performed.

Hemorphins act as homeostatic agents in response to endotoxin-induced stress.

The effect of synthetic LVV-hemorphin-7 and hemorphin-7 on hypothalamo-pituitary-adrenocortical axis activity in response to endotoxin-induced stress was studied. The intraperitoneal (ip) endotoxin (lipopolysaccaride, LPS) (0.5 mg/kg) administration in combination with hemorphin (1 mg/kg) induce significant decrease in plasma corticosterone and modest decrease in plasma levels of tumor necrosis factor-alpha (TNFalpha) in compare with elevated levels of both corticosterone and TNFalpha in plasma of rats received LPS administration alone.

ICPLQuant - A software for non-isobaric isotopic labeling proteomics.

The main goal of many proteomics experiments is an accurate and rapid quantification and identification of regulated proteins in complex biological samples. The bottleneck in quantitative proteomics remains the availability of efficient software to evaluate and quantify the tremendous amount of mass spectral data acquired during a proteomics project. A new software suite, ICPLQuant, has been developed to accurately quantify isotope-coded protein label (ICPL)-labeled peptides on the MS level during LC-MALDI and peptide mass fingerprint experiments.

Transmembrane domain-mediated orientation of receptor monomers in active VEGFR-2 dimers.

Vascular endothelial growth factors (VEGFs) activate cellular receptor tyrosine kinases (RTKs) such as VEGFR-1, -2, and -3. These receptors are activated upon ligand binding to the extracellular receptor domain (ECD), resulting in receptor dimerization and activation of the intracellular kinase domain. Here we investigated the molecular mechanism of activation of the human VEGFR-2 expressed in human HEK293, monkey COS-1, and porcine aortic endothelial cells.

pH dependence and gene structure of inaA in Escherichia coli.

The weak-acid-inducible locus inaA in Escherichia coli was mapped to 48.6 min by P1 cotransduction of inaA Mud lac fusions and linked Tn10 insertions. The inaA1::lac fusion tested negative for phenotypes characteristic of mutations in the nearby locus ubiG.

Transcriptional organization and regulation of the nosiheptide resistance gene in Streptomyces actuosus.

The nosiheptide resistance gene (nshR) and a putative regulatory gene (nshA) are found together on a 2326 bp BamHI-PstI DNA fragment isolated from Streptomyces actuosus ATCC 25421. The putative regulatory gene, nshA, situated upstream from the nosiheptide resistance gene in the 2326 bp DNA fragment, contains apparent DNA-binding and RNA-binding domains. Interruption of nshA in the chromosome of S.

Genetic analysis of potassium transport loci in Escherichia coli: evidence for three constitutive systems mediating uptake potassium.

The analysis of mutants of Escherichia coli that require elevated concentrations of K+ for growth has revealed two new genes, trkG, near minute 30 within the cryptic rac prophage, and trkH, near minute 87, the products of which affect constitutive K+ transport. The analysis of these and other trk mutations suggests that high rates of transport, previously considered to represent the activity of a single system, named TrkA, appear to be the sum of two systems, here named TrkG and TrkH. Each of these two is absolutely dependent on the product of the trkA gene, a cytoplasmic protein associated with the inner membrane (D.

Biosynthesis of anthraquinones by interspecies cloning of actinorhodin biosynthesis genes in streptomycetes: clarification of actinorhodin gene functions.

Streptomyces galilaeus ATCC 31133 and ATCC 31671, producers of the anthracyclines aclacinomycin A and 2-hydroxyaklavinone, respectively, formed an anthraquinone, aloesaponarin II, when they were transformed with DNA from Streptomyces coelicolor containing four genetic loci, actI, actIII, actIV, and actVII, encoding early reactions in the actinorhodin biosynthesis pathway. Subcloning experiments indicated that a 2.8-kilobase-pair XhoI fragment containing only the actI and actVII loci was necessary for aloesaponarin II biosynthesis by S.

Nucleotide sequence and transcriptional analysis of the nosiheptide-resistance gene from Streptomyces actuosus.

The nucleotide (nt) sequence of a 2326-bp BamHI-PstI DNA fragment previously isolated from Streptomyces actuosus ATCC25421 that confers resistance to the thiopeptide antibiotics, nosiheptide (Nh) and thiostrepton (Ts) upon Streptomyces lividans 1326 was determined. Two open reading frames (ORFs) were found in this 2326-bp sequence; one containing 699 nt and another of 822 nt, both reading in the same direction. The Nh-resistance gene determinant (nsh) is encoded by orf822, as determined by the 74% identity of the deduced amino acid sequence of its gene product to that of the 23S rRNA methylase encoded by the Ts-resistance gene (tsr) of Streptomyces azureus.

K+-transport protein TrkA of Escherichia coli is a peripheral membrane protein that requires other trk gene products for attachment to the cytoplasmic membrane.

The TrkA protein, which is essential for the activity of the constitutive Trk K+-uptake system of Escherichia coli, is a peripheral membrane protein. The protein was detected in immunoblots by polyclonal antibodies to sodium dodecyl sulfate-denatured TrkA protein. In extracts from wild-type cells equal amounts of TrkA were found in the membrane and soluble fractions, suggesting that membrane binding is relatively weak.

Molecular cloning of the nosiheptide resistance gene from Streptomyces actuosus ATCC 25421.

An 8.5 kb BamHI DNA fragment conferring resistance to nosiheptide, a peptide antibiotic of the 'thiostrepton group', was cloned from Streptomyces actuosus ATCC 25421 in Streptomyces lividans 1326. Two BamHI fragments of S.

Tetracycline resistance element of pBR322 mediates potassium transport.

The tetracycline resistance element of plasmid pBR322 partially complements the potassium transport defect of Escherichia coli K-12 mutants having markedly impaired K+ transport. The plasmid increases K+ transport. The Tn10 element does not result in increased transport, demonstrating that the effect is not general for elements that increase resistance to tetracycline.