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1.
During a period of several weeks, more than 100 sheep died at a Hungarian farm. The animals exhibited fleece loosing, and hemorrhaging was the most important autopsy finding. Pasteurella haemolytica was cultured from various organs. The bedding straw was abundantly covered with Stachybotrys atra, and removal of the straw stopped the disease. Methanol extraction of the bedding straw followed by solvent partitioning, column chromatography, preparative thin-layer chromatography, and high-pressure liquid chromatography led to the isolation of satratoxins G and H, which were characterized by thin-layer chromatography, high-pressure liquid chromatography, and mass spectroscopy. This is the first isolation and characterization of toxins from a field sample of material responsible for an outbreak of stachybotryotoxicosis.  相似文献   

2.
Chemical identity of tryptensin with angiotensin.   总被引:3,自引:1,他引:2       下载免费PDF全文
K Arakawa  M Yuki    M Ikeda 《The Biochemical journal》1980,187(3):647-653
Tryptensin, a vasopressor substance generated from human plasma protein fraction IV-4 by trypsin, has been isolated and the amino acid composition analysed. The procedures used for the isolation were: (a) adsorption of the formed tryptensin on Dowex 50W (X2; NH4+ form); (b) gel filtration through Sephadex G-25; (c) cation-exchange chromatography on CM-cellulose; (d) anion-exchange chromatography on DEAE-cellulose; (e) re-chromatography on CM-cellulose; (f) gel filtration on Bio-Gel P-2; (g) partition chromatography on high-pressure liquid chromatography. The homogeneity of the isolated tryptensin was confirmed by thin-layer chromatography and thin-layer electrophoresis. The amino acid analysis of the hydrolysate suggested the following proportional composition: Asp, 1; Val, 1; Ile, 1; Tyr, 1; Phe, 1; His, 1; Arg, 1; Pro, 1. This composition is identical with that of human angiotensin.  相似文献   

3.
High-pressure liquid chromatography, utilizing reverse phase μ Bondapak C18 columns and elution with increasing acetonitrile concentrations, has been used to resolve amino acid phenylthiohydantoins obtained from the automated Edman degradation of proteins. Assignment of identity to residues which are difficult to distinguish or identify conclusively by other conventional techniques is easily achieved by high-pressure liquid chromatographic techniques. The use of high-pressure liquid chromatography, in parallel with gas-liquid and polyamide thin-layer chromatography, allows unequivocal assignments of identity to amino acid phenylthiohydantoins obtained in protein sequencing. Single protein sequence determinations can be extended by 20 to 100% by the use of high-pressure liquid chromatography with rapid, accurate, and quantitative identifications of amino acid phenylthiohydantoins.  相似文献   

4.
Different radioactive precursors were added to 8-day potato-dextrose liquid cultures of Aspergillus terreus 23-1. Territrems were isolated from chloroform extracts of the cultures at day 14 and purified by thin-layer chromatography and high-pressure liquid chromatography. The territrem B obtained was treated with alkaline hydrogen peroxide, and 3, 4, 5-trimethoxy benzoic acid was isolated from an ethyl acetate extract of the reaction mixture and purified by thin-layer chromatography and high-pressure liquid chromatography. By comparison of the specific radioactivities of territrem B and its cleaved aromatic product (disintegrations per minute per micromole of compound), it was demonstrated that the radioactivity of territrem B was located mainly on its aromatic moiety when [U-C]shikimate, l-[methyl-C]methionine, and l-[methyl-H]methionine were precursors; however, the radioactivity of territrem B was located mainly on its nonaromatic moiety when [2-C]mevalonate was the precursor. Mevinolin, a specific inhibitor of beta-hydroxyl beta-methyl glutaryl coenzyme A reductase, was shown to inhibit production of territrems by A. terreus 23-1. When [U-C]acetate was used as a precursor, mevinolin inhibited the incorporation of radioactive carbon into territrem but mevinolin did not inhibit incorporation of radioactive carbon from [2-C]mevalonate into territrem.  相似文献   

5.
The oxidation of biphenyl by Cyanobacterium, Oscillatoria sp., strain JCM was studied. The organism grown photoautotrophically in the presence of biphenyl oxidized biphenyl to form 4-hydroxybiphenyl. The structure of the metabolite was elucidated by ultraviolet and mass spectra and shown to be identical to authentic 4-hydroxybiphenyl. In addition this metabolite had properties indentical to 4-hydroxybiphenyl when analyzed by thin-layer and high-pressure liquid chromatography. Experiments with [14C]-biphenyl showed that over a 24 h period the organism oxidized 2.9% of the added biphenyl to ethyl acetate-soluble products.Abbreviations tlc thin-layer chromatography - hplc high pressure liquid chromatography  相似文献   

6.
Corn cultured with Aspergillus flavus to produce a high level of aflatoxin was ammoniated at 37 degrees C for 21 days. An extract of the ammoniated corn was separated by thin-layer chromatography, followed by reversed-phase high-pressure liquid chromatography. Examination of the fractions by tandem mass spectrometry led to detection of aflatoxin D1 as a product of the corn ammoniation process.  相似文献   

7.
Corn cultured with Aspergillus flavus to produce a high level of aflatoxin was ammoniated at 37 degrees C for 21 days. An extract of the ammoniated corn was separated by thin-layer chromatography, followed by reversed-phase high-pressure liquid chromatography. Examination of the fractions by tandem mass spectrometry led to detection of aflatoxin D1 as a product of the corn ammoniation process.  相似文献   

8.
Three O-acylated, unsaturated sialic acids, N-acetyl-9-O-acetyl-, N-acetyl-9-O-lactoyl-, and 2-deoxy-N-glycoloyl-9-O-lactoyl-2,3-didehydroneuraminic acid (5-acetamido-9-O-acetyl-, 5-acetamido-9-O-lactoyl-, and 2,6-anhydro-3,5-dideoxy-5-glycoloylamido-9-O-lactoyl-D-glycero-D-g alacto-non-2- enonic acid) were isolated from urine or submandibular glands of rat, pig, and cow. Mass spectrometric evidence for the existence of 2,3-unsaturated 9-O-acetyl-N-glycoloylneuraminic acid in porcine urine was also obtained. The sialic acids were purified by dialysis, gel- and ion-exchange chromatography, and preparative thin-layer chromatography. They were analyzed by thin-layer chromatography, high-pressure liquid chromatography, and capillary gas-liquid chromatography-mass spectrometry. For comparison, O-acetylated unsaturated sialic acids were synthesized.  相似文献   

9.
A heat-resistant, low-molecular-weight toxin was isolated from semisolid potato dextrose agar medium after inoculation with Flavobacterium farinofermentans sp. nov., which was isolated from fermented corn meal that caused some outbreaks of food poisoning in China. The toxin was purified by solvent partition, Sephadex LH-20 gel filtration, and C-18 reversed-phase column chromatography. Thin-layer chromatography and high-pressure liquid chromatographic methods were developed for the identification and analysis of the toxin. The purified toxin exhibited a single spot in thin-layer chromatography and a single peak in high-pressure liquid chromatography and had adsorption maxima at 232 and 267 nm. Mass spectral analysis indicated a molecular weight of 169 with an experimental formula of C9H13O3. The 50% lethal dose of purified toxin in mice (oral) was less than 6.84 mg/kg, but greater than 0.68 mg/kg. Postmortem examination showed that the mice died of some type of neurological and cardiovascular system toxicity. The name Flavotoxin A is being assigned to the toxin.  相似文献   

10.
The muramidase digest of peptidoglycan from Neisseria gonorrhoeae was isolated and analyzed by the use of a reverse-phase, high-pressure liquid chromatography system. As was found previously in the case of Escherichia coli, gonococci peptidoglycan is also composed of a greater number of muropeptides than can be resolved with thin-layer chromatography systems. Preliminary classification of the muropeptide components into subclasses based on O-acetyl modification and degree of cross-linkage was achieved. Examination of a penicillin-susceptible strain and a highly resistant strain with two penicillin-binding protein alterations synthesized distinctly different peptidoglycan structures, as revealed by this technique.  相似文献   

11.
A heat-resistant, low-molecular-weight toxin was isolated from semisolid potato dextrose agar medium after inoculation with Flavobacterium farinofermentans sp. nov., which was isolated from fermented corn meal that caused some outbreaks of food poisoning in China. The toxin was purified by solvent partition, Sephadex LH-20 gel filtration, and C-18 reversed-phase column chromatography. Thin-layer chromatography and high-pressure liquid chromatographic methods were developed for the identification and analysis of the toxin. The purified toxin exhibited a single spot in thin-layer chromatography and a single peak in high-pressure liquid chromatography and had adsorption maxima at 232 and 267 nm. Mass spectral analysis indicated a molecular weight of 169 with an experimental formula of C9H13O3. The 50% lethal dose of purified toxin in mice (oral) was less than 6.84 mg/kg, but greater than 0.68 mg/kg. Postmortem examination showed that the mice died of some type of neurological and cardiovascular system toxicity. The name Flavotoxin A is being assigned to the toxin.  相似文献   

12.
During the NADPH-Fe-induced peroxidation of liver microsomal lipids products are formed which are provided with cytopathological activities. In a previous study one of the major products was identified as an aldehyde of the 4-hydroxyalkenal class, namely 4-hydroxynonenal. In the present study another cytotoxic product has been isolated and identified as 4,5-dihydroxy-2,3-decenal. The isolation was performed by means of thin-layer chromatography and high-pressure liquid chromatography and the structure was ascertained mainly by means of mass spectroscopy of the free aldehyde and of its derivatives. In the absence of NADPH-Fe liver microsomes produced no 4,5-dihydroxydecenal. The inhibitory activity of 4,5-dihydroxydecenal on microsomal glucose-6-phosphatase is somewhat lower than that exhibited by 4-hydroxynonenal. This lower inhibitory activity correlates with the lower capacity to bind to the microsomal protein of 4,5-dihydroxydecenal as compared to 4-hydroxynonenal. The reactivities of the two aldehydes with cysteine were comparable. The production of toxic aldehydes may represent a mechanism by which lipid peroxidation causes deleterious effects on cellular functions.  相似文献   

13.
During the NADPH-Fe-induced peroxidation of liver microsomal lipids products are formed which are provided with cytopathological activities. In a previous study one of the major products was identified as an aldehyde of the 4-hydroxyalkenal class, namely 4-hydroxynonenal. In the present study another cytotoxic product has been isolated and identified as 4,5-dihydroxy-2,3-decenal. The isolation was performed by means of thin-layer chromatography and high-pressure liquid chromatography and the structure was ascertained mainly by means of mass spectroscopy of the free aldehyde and of its derivatives. In the absence of NADPH-Fe liver microsomes produced no 4,5-dihydroxydecenal. The inhibitory activity of 4,5-dihydroxydecenal on microsomal glucose-6-phosphatase is somewhat lower than that exhibited by 4-hydroxynonenal. This lower inhibitory activity correlates with the lower capacity to bind to the microsomal protein of 4,5-dihydroxydecenal as compared to 4-hydroxynonenal. The reactivities of the two aldehydes with cysteine were comparable. The production of toxic aldehydes may represent a mechanism by which lipid peroxidation causes deleterious effects on cellular functions.  相似文献   

14.
In a search for endogenous regulators for cyclic nucleotide phosphodiesterase (3':5'-cyclic-AMP 5'-nucleotidohydrolase, EC 3.1.4.17), we found that the ultrafiltrate of bovine brain homogenate contained a cyclic nucleotide phosphodiesterase inhibitor. The inhibitor-containing fraction was further purified by ion-exchange column chromatography and gel filtration chromatography. The purified inhibitor was found to be a small molecular weight compound which had a maximum absorption at 248 nm. This compound was identified by thin-layer chromatography and high-pressure liquid chromatography as hypoxanthine. We suggest that hypoxanthine may serve as an endogenous regulator for the hydrolysis of cyclic nucleotide by cyclic nucleotide phosphodiesterase.  相似文献   

15.
A method has been developed for extraction and purification of the major bile acids in human feces, and for their quantitative estimation using high-pressure liquid chromatography. Freeze-dried fecal material was extracted with alkaline ethanol and, after removal of neutral steroids, was subjected to thin-layer chromatography, followed by reversed-phase C18 silica cartridge (Sep-Pak) purification. The mixture was further separated into free, and glyco and tauro conjugates by ion-exchange chromatography. Subsequent resolution of individual bile acids was accomplished by HPLC using a counterion pairing method.  相似文献   

16.
14-Hydroxycodeine and norcodeine were rigorously identified as products arising from codeine oxidation by Streptomyces griseus ATCC 10137. Both products were routinely detected in extracted culture filtrates after growth of cells in the presence of codeine for 1 week. Under these conditions, about 4 mol% of the codeine starting material was consumed, with norcodeine and 14-hydroxycodeine representing the only identifiable transformation products (molar ratio, 4:1, respectively). Extraction of a series of culture filtrates and purification of the pooled metabolites by thin-layer and high-pressure liquid chromatography led to the isolation of both biological products, the structures of which were verified by high-resolution mass spectrometry and proton nuclear magnetic resonance spectroscopy. The identities of both biological products were further confirmed by comparison of their spectral properties with those of authentic standards. This is the first report providing structural evidence for the biological formation of 14-hydroxycodeine from codeine and of codeine oxidation by S. griseus.  相似文献   

17.
14-Hydroxycodeine and norcodeine were rigorously identified as products arising from codeine oxidation by Streptomyces griseus ATCC 10137. Both products were routinely detected in extracted culture filtrates after growth of cells in the presence of codeine for 1 week. Under these conditions, about 4 mol% of the codeine starting material was consumed, with norcodeine and 14-hydroxycodeine representing the only identifiable transformation products (molar ratio, 4:1, respectively). Extraction of a series of culture filtrates and purification of the pooled metabolites by thin-layer and high-pressure liquid chromatography led to the isolation of both biological products, the structures of which were verified by high-resolution mass spectrometry and proton nuclear magnetic resonance spectroscopy. The identities of both biological products were further confirmed by comparison of their spectral properties with those of authentic standards. This is the first report providing structural evidence for the biological formation of 14-hydroxycodeine from codeine and of codeine oxidation by S. griseus.  相似文献   

18.
Hydrogenosomes are found in organisms that lack typical mitochondria. Cardiolipin is a phospholipid located exclusively in bacterial membranes and the inner membrane of mitochondria. Here we show, by cell fractionation, thin-layer chromatography, high-pressure liquid chromatography, and matrix-assisted laser desorption ionization-time of flight mass spectrometry that hydrogenosomes of Tritrichomonas foetus, a cattle vaginal parasite, contain cardiolipin, which is strong evidence for its endosymbiotic origin.  相似文献   

19.
Three metabolites were formed from ochratoxin A in the presence of rabbit liver microsomal fractions and NADPH. They were isolated by extraction, thin-layer chromatography, and high-pressure liquid chromatography. Two of them were identified as (4R)- and (4S)-4-hydroxyochratoxin A. It is suggested on the basis of mass and nuclear magnetic resonance spectroscopy that the third metabolite is 10-hydroxyochratoxin A. The formation of the metabolites was inhibited by carbon monoxide and metyrapone and was stimulated when microsomes from phenobarbital-treated animals were used. The results suggest that cytochrome P-450 catalyzes the formation of these metabolites.  相似文献   

20.
L-Phenylalanine and L-tyrosine were completely catabolized through homogentisate by Streptomyces setonii 75Vi2 but only partially degraded by Streptomyces badius 252, Streptomyces sioyaensis P5, Streptomyces viridosporus T7A, and Streptomyces sp. strain V7. Intermediates of catabolism were confirmed by thin-layer, gas, and high-pressure liquid chromatography. Homogentisate 1,2-dioxygenase was present in all cell extracts.  相似文献   

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