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Nicolas Delaleu Heike Immervoll Janet Cornelius Roland Jonsson 《Arthritis research & therapy》2008,10(1):R22
Introduction
Sj?gren's syndrome (SS) is a systemic autoimmune disease that mainly targets the exocrine glands. The aim of this study was to investigate the involvement of 87 proteins measured in serum and 75 proteins analyzed in saliva in spontaneous experimental SS. In addition, we intended to compute a model of the immunological situation representing the overt disease stage of SS. 相似文献3.
Heike Pohla Wolfgang Kuon Piotr Tabaczewski Christa Doerner Elisabeth H. Weiss 《Immunogenetics》1989,29(5):297-307
Several new HLA-B (B8, B51, Bw62)- and HLA-C (Cw6, Cw7)-specific genes were isolated either as genomic cosmid or cDNA clones to study the diversity of HLA antigens. The allele specificities were identified by sequence analysis in comparison with published HLA-B and -C sequences, by transfection experiments, and Southern and northern blot analysis using oligonucleotide probes. Comparison of the classical HLA-A, -B, and -C sequences reveals that allele-specific substitutions seem to be rare events. HLA-B51 codes only for one allelespecific residue: arginine at position 81 located on the 1 helix, pointing toward the antigen binding site. HLA-B8 contains an acidic substitution in amino acid position 9 on the first central sheet which might affect antigen binding capacity, perhaps in combination with the rare replacement at position 67 (F) on the ul helix. HLA-B8 shows greatest homology to HLA-Bw42, -Bw41, -B7, and-Bw60 antigens, all of which lack the conserved restriction sites Pst I at position 180 and Sac I at position 131. Both sites associated with amino acid replacements seem to be genetic markers of an evolutionary split of the HLA-B alleles, which is also observed in the leader sequences. HLA-Cw7 shows 98% sequence identity to the JY328 gene. In general, the HLA-C alleles display lower levels of variability in the highly polymorphic regions of the 1 and 2 domains, and have more distinct patterns of locus-specific residues in the transmembrane and cytoplasmic domains. Thus we propose a more recent origin for the HLA-C locus. 相似文献
4.
Heike Schmidt Rüdiger Bode Ida A. Samsonova Dieter Birnbaum 《Applied microbiology and biotechnology》1989,31(5-6):463-466
Summary Mutants of Candida maltosa were isolated that lacked saccharopine reductase (lys9) and saccharopine dehydrogenase (lys1) and were able to accumulate -aminoadipate--semialdehyde (AASA) in the cell and excrete it into the culture medium. The effects of incubation time, lysine concentration, and carbon and nitrogen sources on AASA production were examined. In the presence of 15 g glucose/1, 1.25 g NH4H2PO4/l and 50 mg l-lysine/l in a minimal salt medium C. maltosa G285 (lys1) produced about 80–90 mg AASA/l during 48 h of growth. A simple and rapid procedure to isolate AASA from the medium using Dowex 50X4 is described. 相似文献
5.
Activation of T cell-derived lymphokine genes in T cells and fibroblasts: effects of human T cell leukemia virus type I p40x protein and bovine papilloma virus encoded E2 protein. 总被引:34,自引:1,他引:33
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S Miyatake M Seiki R D Malefijt T Heike J Fujisawa Y Takebe J Nishida J Shlomai T Yokota M Yoshida 《Nucleic acids research》1988,16(14A):6547-6566
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Coenzyme A-linked acetaldehyde dehydrogenase (ACDH) of ethanol-grown cells of Acetobacterium woodii was purified to apparent homogeneity; a 28-fold purification was achieved with 13% yield. The enzyme proved to be oxygen-sensitive and was inactive in the absence of dithioerythritol. During the purification procedure addition of 1 mM MgCl2 was necessary to maintain enzyme activity. Alcohol dehydrogenase (ADH) activity was separated from ACDH during anion exchange chromatography using DEAE Sephacel. A part of the ACDH activity coeluted with ADH, but both could be separately eluted from a Cibacron Blue 3GA-Agarose column, revealing the same subunit structure and activity band for ACDH as found before and, thus, indicating an aggregation of the enzyme. The remaining ADH activity could be separated by gel filtration. For the native ACDH a molecular mass of 255 kDa was determined by polyacrylamide gel electrophoresis and of 272 kDa by gel filtration using Superose 12. The enzyme subunit sizes were 28 kDa and 40 kDa, respectively, indicating a 44 structure for the active form. The enzyme catalyzed the oxidation of several straight chain aldehydes although it was most active with acetaldehyde. NADH strongly inhibited oxidation of acetaldehyde whereas NADPH had no effect. The inhibition was noncompetitive.Non-standard abbrevations ACDH
acetaldehyde dehydrogenase
- ADH
alcohol dehydrogenase
- CHES
2-(N-cyclohexylamino)-ethanesulfonate
- DTE
dithioerythritol
- KP-buffer
25 mM K-PO4, pH 7.5, containing, 4 mM DTE
- MES
2-(N-morpholino)-ethanesulfonate
- TAPS
N-Tris-(hydroxymethyl)-methyl-3-aminopropa-nesulfonate 相似文献
8.
W. Junger H. J. Dahmen 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,169(5):641-646
Waterstriders (Gerris paludum) often try to maintain a nearly stationary position on a moving water surface. Passive motion is restricted to 3 degrees of freedom: yaw, longitudinal, and transverse displacement. They correct for passive rotation and translation by distinct behavioral sequences. The compensatory behavior is predominantly visually controlled.
The restriction of degreess of freedom reduces the complexity of the motion-induced visual flow field. Each motion component induces its own flow field component. We propose that those areas of the visual field are preferred for analysis where the directions of the 3 flow field components differ most. These areas (Figs. 2 and 3) have their largest extent at 45° above the horizon. 相似文献
1. | When waterstriders are rotated and translated simultaneously, they are able to discriminate their own rotation and translation visually. |
2. | They discriminate their rotation from their translation even if the visible pattern is restricted to a monocular visual field. |
3. | They detect rotation only if they see an extended pattern. |
9.
Summary Cryosubstitution provides an improved ultrastructural preservation of the two plant pathogensVenturia inaequalis andErysiphe graminis when compared to conventional preparation methods. Further, freezing the infected whole leaf material on a copper block cooled with liquid helium gave better results than those observed with the propane plunging method. Novel observations concerning the fungal stroma and haustoria were made which showed ribosomes organized into groups that were evenly distributed throughout the cytoplasm of both fungi. Stretches of rough endoplasmic reticulum were present, and microtubules were seen, sometimes associated with mitochondria. A large number of darkly staining vacuoles were observed in both fungi. The polarity of organelles and microtubules along the longitudinal axis of the haustorial body ofE. gramnis and along the growing direction of subcuticular stroma and runner hypha ofV. inaequalis was evident. InE. graminis filasomes were observed, as were Golgi-like bodies. These new observations, together with the advantages of the cryosubstitution technique, can serve as a basis for further studies in understanding host-parasite interactions. 相似文献
10.
Arabidopsis thaliana lines have been isolated that are insensitive to the fungal toxin fusicoccin (FC). Initial screening was done by selecting for plants that either grew well on high concentrations of FC or did not respond to FC by increases in H+-extrusion. All selected plants were tested, in several additional rounds of screening, for binding to microsomal proteins of a 3H-labeled radioligand of fusicoccin. A novel assay allowing for the direct selection of individual plants exhibiting reduced binding of FC was developed and used as screening procedure. Independent variant lines (43) with stably expressed, reduced binding of FC were isolated and subjected to a detailed characterization of their binding sites. The lines could be subdivided into several distinct classes with respect to these characteristics. In class-I lines, the data indicate a partial conversion of high-affinity binding sites to a low-affinity state. In class-II lines, the affinity of the binding site to FC is strongly reduced while the number of sites, as well as several other biochemical parameters, is completely unchanged, suggesting a specific alteration in the properties of the fusicoccin-binding protein. In class-III lines, the ligand-binding protein complex, while retaining its high affinity, is destabilized at supraoptimal concentrations of FC (such as those used for screening). In wild-type plants, only the high-affinity binding site was detected. Combined, these data prove that the high-affinity sites represent the plant's FC receptor.Abbreviations Ao
binding site concentration
- FC
fusicoccin
- FCBP
fusicoccin-binding protein
- FCol
9-nor-8-hydroxyfusicoccin
- KD
dissociation constant of the FCBP-radioligand complex
We are grateful to Iris Sandorf and Gudrun Henrichs for excellent technical assistance. This work was supported by the Deutsche Forschungsgemeinschaft, Bonn, Germany and by Fonds der Chemischen Industrie (literature provision). 相似文献