Medical specific study

We are interested in constructing a model for the substrate-bindingsiteof fattyacidelongase-13-ketoacylCoAsynthase (FAE1 KCS),the enzyme responsible forproductionof very long chain fatty acids of plant seed oils.Arabidopsis thaliana andBrassica napusFAE1 KCS enzymes are highly homo-logous but the seed oil content of these plants suggests that their substrate specificities differ with respect to acyl chain length.

10p research12 29-04-2013 28 3   Download

A differential display method was used to study genes the expression of which is altered during growth inhibition induced by medroxyprogesterone acetate (MPA). A tran-script of G-protein-coupled receptor 30 (GPR30) was upregulated by MPA in estrogen-treated MCF-7 breast cancer cells. Northern-blot analysis showed a progestin-specific primary target gene, which was enhanced by prog-esterone and different progestins, but not by dihydrotestos-terone or dexamethasone, and which was abrogated by antiprogestin RU486....

6p research12 29-04-2013 46 2   Download

Short-chaindehydrogenases/reductases (SDRs) are enzymes of great functional diversity. Even at sequence identities of typically only 15–30%, specific sequence motifs are detect-able, reflecting common folding patterns. We have devel-oped a functional assignment scheme based on these motifs and we find five families. Two of these families were known previously and are called
classical and
extended families, but they are now distinguished at a further level based on coenzyme specificities.

9p research12 23-04-2013 38 3   Download

We have characterized the biochemical properties of the testis and brain-specific 105-kDa protein which is cross-reacted with an anti-bovine HSP90 antibody. The protein was induced ingermcells byheat stress, resulting inaprotein which is one of the heat shock proteins [Kumagai, J., Fuk-uda, J., Kodama, H., Murata, M., Kawamura, K., Itoh, H. &Tanaka,T. (2000)Eur. J.Biochem.267, 3073–3078]. In the present study,we characterized thebiochemical propertiesof the protein.

10p tumor12 22-04-2013 30 3   Download

Biotin protein ligase (BPL) catalyses the biotinylation of the biotin carboxyl carrier protein (BCCP) subunit of acetyl CoAcarboxylase and this post-translational modificationof a single lysine residue is exceptionally specific. The exact details of the protein–protein interactions involved are unclear as a BPL:BCCP complex has not yet been isolated. Moreover, detailed information is lacking on the composi-tion, biosynthesis and role of fatty acids in hyperthermo-philic organisms.

11p tumor12 20-04-2013 32 2   Download

PSA (prostate-specific antigen), the most useful serum marker for prostate cancer, is encoded by thehKLK3gene and is present in the serumas amixture of several molecular species. This work was performed to identify the hKLK3 transcripts in order to determine how many proteins resembling PSA are synthesized from thehKLK3gene and secreted in blood. Combined Northern blotting, molecular cloninganddatabase searching showed that thehKLK3gene produces at least 15 transcripts ranging in size from 0.7 to 6.1 kb. Polysomal distribution analysis revealed that the transcripts shorter than 3.

9p tumor12 20-04-2013 55 2   Download

As human choriocarcinoma cells display many of the biochemical and morphological characteristics reported for in utero invasive trophoblast cells we have studied cho-lesterol supply from high density lipoproteins (HDL) to these cells.Binding properties of 125 I-labeled HDL sub-class 3 (HDL3)at4
C were similar for BeWo, JAr, and Jeg3 choriocarcinoma cell lines while degradation rates at 37
C were highest for BeWo.

12p tumor12 20-04-2013 34 2   Download

TheST2gene, which is specifically induced by growth sti-mulation in fibroblasts, encodes interleukin-1 receptor-rela-tedproteins and iswidely expressed in hematopoietic, helper T, and various cancer cells. However, the physiological as well as pathological functions of the ST2 gene products are not yet fully understood. In this study, we analyzed the expression of theST2gene in human glioma cell lines and human brain tumor samples with real-time polymerase chain reactionmethod,

8p tumor12 20-04-2013 48 4   Download

Strains ofPseudomonas syringaepv. porri are characterized by a number of pathovar-specific phenotypic and genomic characters and constitute a highly homogeneous group. Using monoclonal antibodies, they all were classified in a novelP. syringaeserogroup O9. The O polysaccharides (OPS) isolated from the lipopolysaccharides (LPS) of P. syringaepv.

8p tumor12 20-04-2013 38 3   Download

The O-specific polysaccharide ofCitrobacter braakiiPCM 1531 (serogroupO6) was isolated bymild acid hydrolysis of the lipopolysaccharide (LPS) and found to containD-fucose, L-rhamnose, 4-deoxy-D-arabino-hexose andO-acetyl groups in molar ratios 2 : 1 : 1 : 1. On the basis of methylation analysis and 1 Hand13 C NMR spectroscopy data, the structure of the branched tetrasaccharide repeating unit of theO-specific polysaccharidewas established.

7p fptmusic 16-04-2013 51 4   Download

Flexibacter maritimus, a Gram-negative bacterium, is a fish pathogenresponsible fordisease infinfishspecies andacause of cutaneous erosiondisease in sea-caged salmonids. For the development of serology based diagnostics, protective vac-cines, and a study of pathogenesis, the structural analysis of the lipopolysaccharide (LPS) producedby the bacteriumhas been undertaken. We now report that an acidic O-specific polysaccharide, obtained by mild acid degradation of the F. maritimusLPSwas found to be composed of a disac-...

6p fptmusic 16-04-2013 45 3   Download

To learn about the correlation between allostery and ligand binding of the Tet repressor (TetR) we analyzed the effect of mutations in the DNA read-ing head–core interface on the effector specific TetR i2 variant. The same mutations in these subdomains can lead to completely different activities, e.g. the V99G exchange in the wild-type leads to corepression by 4-ddma-atc without altering DNA binding. However, in TetR i2 it leads to 4-ddma-atc dependent repression in combination with reduced DNA binding in the absence of effector. ...

10p fptmusic 11-04-2013 38 3   Download

Depolarization and repolarization phases (D and R phases, respectively) of mitochondrial potential fluctuations induced by photoactivation of the fluorescent probe tetramethylrhodamine methyl ester (TMRM) were ana-lyzed separately and investigated using specific inhibitors and substrates. The frequency of R phases was significantly inhibited by oligomycin and aurovertin (mitochondrial ATP synthase inhibitors), rotenone (mitochond-rial complex I inhibitor) and iodoacetic acid (inhibitor of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase)....

11p awards 06-04-2013 48 2   Download

BacterialRNApolymerase (RNAP) is the central enzyme of gene expression that is responsible for the synthesis of all types of cellular RNAs. The process of transcription is accompanied by complex structural rearrangements of RNAP. Despite the recent progress in structural studies of RNAP, detailed mechanisms of conformational changes of RNAP that occur at different stages of transcription remain unknown.

11p awards 05-04-2013 42 2   Download

The specificity of the Spodoptera frugiperda digestive b-glycosidase (Sfbgly50) for fucosides, glucosides and galactosides is determined by noncovalent interactions of glycone6-OHandglycone 4-OHwith the active-site residues Q39andE451.Site-directedmutagenesisandenzymesteady-state kinetics were described, showing that replacement of E451 with glutamine increased the preference of Sfbgly50 for glucosides in comparison to galactosides, whereas replacing E451 with serine had the opposite effect.

9p awards 05-04-2013 46 3   Download

The tumor suppressor protein, p53, selectively binds to supercoiled (sc) DNA lacking the specific p53 consensus binding sequence (p53CON). Using p53 deletion mutants, we have previously shown that the p53 C-terminal DNA-binding site (CTDBS) is critical for this binding.

12p awards 05-04-2013 43 5   Download

The tissue-specific transcription factorsHNF1aandHNF1b are closely related homeodomain proteins conserved in vertebrate evolution. Heterozygous mutations in human HNF1b 1 but not inHNF1agenes are associated with kidney malformations. Overexpression of HNF1b in Xenopus embryos leads to defective pronephros development, while HNF1ahas no effect. We have defined the regions respon-sible for this functional difference between HNF1band HNF1ain transfected HeLa cells as well as in injected Xenopusembryos. ...

14p awards 05-04-2013 44 3   Download

Differences in the substrate specificity ofa-glucosidases should be due to the differences in the substrate binding and the catalytic domains of the enzymes. To elucidate such differences of enzymes hydrolyzinga-1,4- and a-1,6-glu-cosidic linkages, twoa-glucosidases,maltase and isomaltase, from Saccharomyces cerevisiaewere cloned and analyzed. The cloned yeast isomaltase and maltase consisted of 589 and 584 amino acid residues, respectively. There was 72.1% sequence identity with 165 amino acid alterations between the two a-glucosidases. ...

7p awards 05-04-2013 43 6   Download

The polyamines putrescine, spermidine and spermine are organic cations shown to participate in a bewildering num-ber of cellular reactions, yet their exact functions in inter-mediary metabolism and specific interactions with cellular components remain largely elusive. Pharmacological inter-ventions have demonstrated convincingly that a steady supply of these compounds is a prerequisite for cell prolif-eration to occur.

18p dell39 03-04-2013 41 5   Download

Cyclic AMP responsive element (CRE)-binding protein (CREB) is known to activate transcription when its Ser133 is phosphorylated. Two independ-ent investigations have suggested the presence of Ser133-independent acti-vation. One study identified a kinase, salt-inducible kinase (SIK), which repressed CREB; the other isolated a novel CREB-specific coactivator, transducer of regulated CREB activity (TORC), which upregulated CREB activity.

19p dell39 27-03-2013 41 4   Download