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101.
We have purified for the first time from green leaves a multifunctional protein (MFP) involved in fatty acid -oxidation. The protein, designated MFP IV, was extracted from green leaves of three-week-old cucumber (Cucumis sativus L.) plants. Chromatography on cation exchanger, separation on hydroxylapatite, and fast-protein liquid chromatography on Phenylsuperose led to a more than 7000-fold purification and to the isolation of an apparently homogeneous 80-kDa monomeric protein. This protein is immunologically related to the glyoxysomal MFP II, as evidenced by immunodecoration with antiserum raised against MFP II. Comparison of molecular masses of all MFPs presently known revealed that the MFP prepared from green leaves (MFP IV) is distinct from MFP II (76.5 kDa) and MFP I (74 kDa) from dark-grown cotyledons. By including other properties in this comparison, we demonstrated that MFP IV can also be distinguished from the glyoxysomal MFP III (81 kDa) and the bacterially expressed MFP-a (80 kDa). Moreover, MFP IV is a constituent of leaf peroxisomes and contains the activities of 2-enoyl-CoA hydratase (EC 4.2.1.17),l-3-hydroxyacyl-CoA dehydrogenase (EC 1.1.1.35) and 3-hydroxyacyl-CoA epimerase.Abbreviation MFP
multifunctional protein
This work was supported by grants from the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie. 相似文献
102.
Prof. Dr. Wolf-Christian Dullo Dr. Marcos Gektidis Prof. Dr. Stjepko Golubic Dr. Georg A. Heiss Dipl. Biol. Heike Kampmann Dr. William Kiene Dipl. Ökol. Dieter K. Kroll Dipl. Biol. Martin L. Kuhrau Dr. Gudrun Radtke Dr. John G. Reijmer Dr. Götz B. Reinicke Prof. Dr. Dietrich Schlichter Prof. Dr. Helmut Schuhmacher Klaus Vogel 《Facies》1995,32(1):145-188
103.
Cyanuric acid in high concentrations (15.5 mm) was degraded completely by Pseudomonas sp. NRRL B-12228 independently of glucose concentration. In the batch fermentations there was a relation between the glucose concentration, on the one hand, and the liberation of ammonia or production of protein, on the other. The greater the supply of carbon, the more biomass was produced, and fewer NH
inf4
sup+
ions were released. Continuous fermentations using adsorbed cells could be performed to degrade cyanuric acid. In spite of different glucose feeding there was only a negligible difference in residues of s-triazine. In a one-step continuous system with dilution rates between 0.021 h–1 and 0.035 h–1, even a ratio of 0.65 between glucose and cyanuric acid was not sufficient to degrade the cyanuric acid supplied (320–540 mol l–1 h–1) completely. When a continuous two-step system was applied with dilution rates between 0.035 h–1 and 0.056 h–1, the consumption of carbon source could be minimized while s-triazine degradation up to 860 mol l–1 h–1 was complete. In this way the ratio between glucose and cyanuric acid could be increased to 0.25 (molar C:N ratio = 0.33:1). Thereby the process was made considerably more economic. 相似文献
104.
Small intensely fluorescent (SIF) cells are paraganglionic cells derived from sympathicoblasts which may serve as interneurons,
endo-/paracrine cells or arterial chemoreceptors within sympathetic ganglia. Like paraganglionic cells of other locations,
e.g., carotid body glomus cells, they are responsive to hypoxia. Recent studies on glomus cells and other hypoxia-sensing
cells suggested the involvement of a b
558
-type cytochrome and intracellular generation of H2O2 in the process of oxygen sensing. In the present study, we demonstrate the occurrence of the small subunit of cytochrome b
558
, p22phox, in SIF cells of guinea-pig sympathetic ganglia by immunohistochemistry using two different antisera. H2O2 production was monitored in explanted intact superior cervical ganglia of 2-day-old rats by confocal laser scanning analysis
of rhodamine 123 fluorescence generated due to oxidation of dihydrorhodamine 123 by H2O2. Using this technique, SIF cell clusters appeared as sites of highest H2O2 production within the ganglia. Thus, SIF cells exhibit two key features of an oxidase system generating reactive oxygen species.
This may be involved in the proposed chain of events in oxygen sensing, but alternative cellular functions of this system
have also to be considered.
Accepted: 19 September 1996 相似文献
105.
A. H. N. Hopman Sandra Claessen Ernst J. M. Speel 《Histochemistry and cell biology》1997,108(4-5):291-298
We describe the brightfield microscopical detection of multiple DNA target sequences in cell and tissue preparations. For
this purpose, chromosome-specific DNA probes labelled with biotin, digoxigenin or fluorescein were simultaneously hybridised
and detected by enzyme cytochemistry using two horseradish peroxidase (PO) reactions and one alkaline phosphatase (APase)
reaction. For triple-colour detection on single cell preparations, the combination of the enzyme precipitates PO/diaminobenzidine
(DAB, brown colour), APase/fast red (FR, red colour) and PO/tetramethylbenzidine (TMB, green colour) resulted in an accurate
detection of DNA targets. Embedding of the preparations in a thin cross-linked protein layer further stabilised the enzyme
reaction products. For in situ hybridisation on tissue sections, however, this detection procedure showed some limitations
with respect to both the stability of the APase/FR and PO/TMB precipitates, and the sequence of immunochemical layers in multiple-target
procedures. For this reason, the APase/FR reaction was replaced by the APase/new fuchsin (NF, red colour) reaction and the
washing steps after the PO/TMB reaction were restricted to the use of phosphate buffer pH 6.0. Furthermore, to improve the
efficiency of the ISH reaction, APase/NF was applied in an avidin-biotin complex detection system and, to avoid target shielding
in the triple-target ISH, the third primary antibody was applied prior to the second enzyme cytochemical reaction. These adaptations
resulted in stable, well contrasting brown, red and green coloured precipitates. After quick haematoxylin counterstaining,
the tissue preparations were directly mounted in phosphate buffer and, optionally, embedded in the cross-linked protein layer.
Accepted: 27 June 1997 相似文献
106.
Antoni Rozalski Lore Brade Paul Kosma Richard Moxon Shoichi Kusumoto & Helmut Brade 《Molecular microbiology》1997,23(3):569-577
Monoclonal antibodies against the lipopolysaccharide (LPS) of the deep rough mutant I-69 Rd− /b+ of Haemophilus influenzae were obtained after immunization of mice with sheep erythrocytes which had been coated with de- O -acylated LPS. Characterization of antibodies was performed by enzyme immuno assay (EIA) using LPS or neoglycoconjugates containing partial structures of LPS as solid-phase antigens and by haemagglutination with sheep erythrocytes coated with de- O -acylated LPS. Binding data were confirmed by EIA inhibition experiments using deacylated LPS or synthetic partial structures thereof. Three antibodies were specific for 3-deoxy- d - manno -octulopyranosonic acid- (Kdo) 5-phosphate, one for Kdo-4-phosphate, and one required, in addition to a Kdo-phosphate, parts of the phosphorylated glucosamine backbone of lipid A. All antibodies also bound in (i) Western blots to bacterial whole-cell lysates or isolated LPS separated by SDS–PAGE, (ii) bacterial colony blots, and (iii) immunofluorescence with live bacteria. The latter result indicated that Kdo-4- and Kdo-5-phosphate are synthesized by the bacteria and are not the result of phosphate migration. 相似文献
107.
Larvae of the two southern hemisphere lamprey genera, Mordacia and Geotria, possess one and two intestinal diverticula, respectively, each originating at the oesophageal-intestinal junction. These diverticula comprise an inner layer of simple columnar epithelium composed solely of zymogen and mucous cells, a middle layer consisting mainly of a blood sinus, and an outer serosa layer covered by a simple squamous epithelium (mesothelium). The inner surface is highly folded only in Mordacia. The secretion of mucus probably protects the epithelium from the effects of digestive enzymes secreted by the zymogen cells and/or bile, which enters the diverticulum at its tip. Unlike the situation in southern hemisphere lampreys, the zymogen cells of the larvae of holarctic lampreys are located in the anterior intestine, a condition considered to be primitive. It is thus proposed that intestinal diverticula were developed during the evolution of southern hemisphere lampreys. The relocation of zymogen cells in the diverticula increases the area for these cells, and thus the capacity for the synthesis and secretion of digestive enzymes, particularly in Mordacia where the inner surface is folded. 相似文献
108.
Attempts to induce enantioselectivity in the catalytic hydrogenation of unsymmetrically substituted aromatics using covalently bound, well known chiral auxiliaries are described. Marked differences in stereoselectivity and rate of hydrogenolysis are noted as a function of the auxiliary used. Enantioselectivities obtained in the resulting cyclohexyl derivatives are rather poor. © 1995 Wiley-Liss, Inc. 相似文献
109.
Frieder Schauer Kirsten Henning Helmut Pscheidl Rolf M. Wittich Peter Fortnagel Heinz Wilkes Volker Sinnwell Wittko Francke 《Biodegradation》1995,6(2):173-180
Trichosporon beigelii SBUG 752 was able to transform diphenyl ether. By TLC, HPLC, GC, GC-MS, NMR- and UV-spectroscopy, several oxidation products were identified. The primary attack was initiated by a monooxygenation step, resulting in the formation of 4-hydroxydiphenyl ether, 2-hydroxydiphenyl ether and 3-hydroxydiphenyl ether (48:47:5). Further oxidation led to 3,4-dihydroxydiphenyl ether. As a characteristic product resulting from the cleavage of an aromatic ring, the lactone of 2-hydroxy-4-phenoxymuconic acid was identified. The possible mechanism of ring cleavage to yield this metabolite is discussed. 相似文献
110.
Helmut Kroll 《Vegetation History and Archaeobotany》1995,4(1):51-66
Publications on archaeological remains of cultivated plants have been collected, mainly from 1992 and 1993, with some earlier and later ones. A list is given of the finds according to taxon, country, site and age. 相似文献