Evidence is presented that the genome of the infecting poliovirus must be intact in order to achieve inhibition of cellular protein synthesis. Viral particles with a single lethal hit by treatment with hydroxylamine no longer participate in the inhibitory action of the virus. De novo protein synthesis is required for the inhibition to occur. The synthesis of cellular m-RNA is not necessary.
{"title":"Early functions of poliovirus. I. The inhibition of cellular protein synthesis in HeLa cells after infection with active and inactivated poliovirus.","authors":"K Koschel, H Täuber, E Wecker","doi":"10.1515/znb-1971-0813","DOIUrl":"https://doi.org/10.1515/znb-1971-0813","url":null,"abstract":"Evidence is presented that the genome of the infecting poliovirus must be intact in order to achieve inhibition of cellular protein synthesis. Viral particles with a single lethal hit by treatment with hydroxylamine no longer participate in the inhibitory action of the virus. De novo protein synthesis is required for the inhibition to occur. The synthesis of cellular m-RNA is not necessary.","PeriodicalId":23706,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete","volume":"26 8","pages":"798-803"},"PeriodicalIF":0.0,"publicationDate":"1971-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1971-0813","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15501512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photosynthetic NADP reduction, diaphorase and transhydrogenase activity of ferredoxin-NADP reductase (EC 1.6.99.4 or 1.6.1.1, from the alga Bumilleriopsis filiformis) are compared by studying the influence of pyridine nucleotides and 2'-AMP. Together with previous findings dealing with the role of ferredoxin in the two latter activities 7 the results can be compiled as follows: 1. Ferredoxin-NADP reductase has two binding sites: one specific site for ferredoxin and one for pyridine nucleotides whether they are reduced or oxidized. 2. There is no substantial competition between ferredoxin and pyridine nucleotides for their respective binding sites. 3. Diaphorase substrates like dichlorophenolindophenol or methylviologen do not bind at the pyridine nucleotide site. It is suggested that they bind at the ferredoxin site. In vivo, therefore, the diaphorase site of the reductase is occupied by ferredoxin and represents the electron accepting part of the reductase. 4. During transhydrogenase reaction ferredoxin-NADP reductase is reduced by NADPH via the pyridine nucleotide binding site; during NADP reductase reaction the enzyme is reduced by ferredoxin at the ferredoxin site. In both reactions, however, NADP (and other nucleotides) are reduced at the same pyridine nucleotide binding site. Transhydrogenase activity, therefore, appears to be an artefact reaction, which can be found when the isolated reductase is no more reduced by its natural substrate ferredoxin.
{"title":"[Relationship of transhydrogenase and diaphorase activity of ferredoxin-NADP reductase with photosynthetic NADP reduction].","authors":"P Böger","doi":"10.1515/znb-1971-0815","DOIUrl":"https://doi.org/10.1515/znb-1971-0815","url":null,"abstract":"Photosynthetic NADP reduction, diaphorase and transhydrogenase activity of ferredoxin-NADP reductase (EC 1.6.99.4 or 1.6.1.1, from the alga Bumilleriopsis filiformis) are compared by studying the influence of pyridine nucleotides and 2'-AMP. Together with previous findings dealing with the role of ferredoxin in the two latter activities 7 the results can be compiled as follows: 1. Ferredoxin-NADP reductase has two binding sites: one specific site for ferredoxin and one for pyridine nucleotides whether they are reduced or oxidized. 2. There is no substantial competition between ferredoxin and pyridine nucleotides for their respective binding sites. 3. Diaphorase substrates like dichlorophenolindophenol or methylviologen do not bind at the pyridine nucleotide site. It is suggested that they bind at the ferredoxin site. In vivo, therefore, the diaphorase site of the reductase is occupied by ferredoxin and represents the electron accepting part of the reductase. 4. During transhydrogenase reaction ferredoxin-NADP reductase is reduced by NADPH via the pyridine nucleotide binding site; during NADP reductase reaction the enzyme is reduced by ferredoxin at the ferredoxin site. In both reactions, however, NADP (and other nucleotides) are reduced at the same pyridine nucleotide binding site. Transhydrogenase activity, therefore, appears to be an artefact reaction, which can be found when the isolated reductase is no more reduced by its natural substrate ferredoxin.","PeriodicalId":23706,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete","volume":"26 8","pages":"807-15"},"PeriodicalIF":0.0,"publicationDate":"1971-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1971-0815","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15501515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Neuraminidase of Influenza-A-Melbourne virus was competitively inhibited by 2-deoxy-2,3-dehydro-N-acetylneuraminic acid. The inhibition constant (KI) was found to be 5.3 × 10-6 mol/l. The inhibition of different viral neuraminidases was found to vary considerably. The release of Influenza-A-Melbourne virus adsorbed to chick erythrocytes was strongly inhibited by 2-deoxy-2,3-dehydro-N-acetylneuraminic acid. This substance also influenced the replication of neuraminidase containing viruses. The extent of this inhibition was variable. In contrast, the replication of viruses not containing neuraminidase was not affected.
{"title":"[Influence of 2-deoxy-2,3-dehydro-N-acetylneuraminic acid on Myxovirus-neuraminidases and the replication of influenza- and Newcastle disease virus].","authors":"P Meindl, G Bodo, J Lindner, P Palese","doi":"10.1515/znb-1971-0812","DOIUrl":"https://doi.org/10.1515/znb-1971-0812","url":null,"abstract":"Neuraminidase of Influenza-A-Melbourne virus was competitively inhibited by 2-deoxy-2,3-dehydro-N-acetylneuraminic acid. The inhibition constant (KI) was found to be 5.3 × 10-6 mol/l. The inhibition of different viral neuraminidases was found to vary considerably. The release of Influenza-A-Melbourne virus adsorbed to chick erythrocytes was strongly inhibited by 2-deoxy-2,3-dehydro-N-acetylneuraminic acid. This substance also influenced the replication of neuraminidase containing viruses. The extent of this inhibition was variable. In contrast, the replication of viruses not containing neuraminidase was not affected.","PeriodicalId":23706,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete","volume":"26 8","pages":"792-7"},"PeriodicalIF":0.0,"publicationDate":"1971-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15501511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Incorporation of uridine in cleavage stage eggs of the sea urchin Paracentrotus lividus was investigated. It was shown by ion exchange and thin layer chromatography that most of the uridine taken up during the 16-cell stage was converted into UTP with some incorporation into UDP and UMP. Conversion of uridine to these phosphorylated nucleosides occurred throughout early cleavage stages. A very small amount of uridine taken up by cleavage stage eggs is incorporated into RNA heterogeneous in size. This RNA was examined by polyacrylamide gel electrophoresis.
{"title":"Incorporation of uridine in cleavage stage eggs of the sea urchin Paracentrotus lividus.","authors":"L E Bockstahler","doi":"10.1515/znb-1971-0816","DOIUrl":"https://doi.org/10.1515/znb-1971-0816","url":null,"abstract":"Incorporation of uridine in cleavage stage eggs of the sea urchin Paracentrotus lividus was investigated. It was shown by ion exchange and thin layer chromatography that most of the uridine taken up during the 16-cell stage was converted into UTP with some incorporation into UDP and UMP. Conversion of uridine to these phosphorylated nucleosides occurred throughout early cleavage stages. A very small amount of uridine taken up by cleavage stage eggs is incorporated into RNA heterogeneous in size. This RNA was examined by polyacrylamide gel electrophoresis.","PeriodicalId":23706,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete","volume":"26 8","pages":"816-21"},"PeriodicalIF":0.0,"publicationDate":"1971-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1971-0816","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15501516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chloroplasten, Membranproteine, Molekulargewicht, Konformation The lamellar system of chloroplasts, dissolved in concentrated formic acid, may be freed from lipids by dialysis or gel filtration. The structural protein on both sides of the isoelectric region is water-soluble. The molecular weight was determined to be 470 000 at pH 3.0 - 3.4. Electron micrographs reveal disc-like particles of variable diameter but constant thickness. Particles of 100 Å diameter and 50 Å thickness are mainly observed. The limiting viscosity number [η] = 12 (ml/g) demonstrated that the particles are also anisodiametric in solution. It follows from changes in circular dichroism and infrared absorption that the conformation of the polypeptides is altered by the formic acid treatment. The structural protein can be separated into polypeptides in buffers containing dodecylsulphate, yielding a major component of molecular weight 25 000. From these experiments it may be concluded that one protein layer is contained in the thylakoid membrane which is composed of supra-molecular structural elements.
{"title":"[Molecular weight, size and shape of thylakoid-membrane proteins].","authors":"W Menke, H G Ruppel","doi":"10.1515/znb-1971-0818","DOIUrl":"https://doi.org/10.1515/znb-1971-0818","url":null,"abstract":"Chloroplasten, Membranproteine, Molekulargewicht, Konformation The lamellar system of chloroplasts, dissolved in concentrated formic acid, may be freed from lipids by dialysis or gel filtration. The structural protein on both sides of the isoelectric region is water-soluble. The molecular weight was determined to be 470 000 at pH 3.0 - 3.4. Electron micrographs reveal disc-like particles of variable diameter but constant thickness. Particles of 100 Å diameter and 50 Å thickness are mainly observed. The limiting viscosity number [η] = 12 (ml/g) demonstrated that the particles are also anisodiametric in solution. It follows from changes in circular dichroism and infrared absorption that the conformation of the polypeptides is altered by the formic acid treatment. The structural protein can be separated into polypeptides in buffers containing dodecylsulphate, yielding a major component of molecular weight 25 000. From these experiments it may be concluded that one protein layer is contained in the thylakoid membrane which is composed of supra-molecular structural elements.","PeriodicalId":23706,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete","volume":"26 8","pages":"825-31"},"PeriodicalIF":0.0,"publicationDate":"1971-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1971-0818","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15501518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The phases of the cell cycle of Potorous tridactylus (PtK2) cells were determined in vitro by analysis of labeled mitoses for 37-½ hours after a tritiated thymidine pulse. The mean duration of DNA synthesis (tS) was 8 h. The mean duration of the gap phase before appearance of labeled mitoses was 5 h. Whereas the duration of the cell cycle (tC) based on analysis of labeled mitoses was 30 h, the doubling time (tD) derived from cell counts in the same cultures was only about 23 h. The analysis of the indices of labeled nuclei and mitoses suggests a stimulation of cells at the time of pulse labeling, which was maximal after beginning of the gap phase before DNA-synthesis, and possibly caused the observed difference between tC and tD.
{"title":"Cell cycle analysis and stimulation of rat kangaroo cells (PtK 2 ) after pulse labeling.","authors":"P R Lorenz, J W Ainsworth","doi":"10.1515/znb-1971-0717","DOIUrl":"https://doi.org/10.1515/znb-1971-0717","url":null,"abstract":"The phases of the cell cycle of Potorous tridactylus (PtK2) cells were determined in vitro by analysis of labeled mitoses for 37-½ hours after a tritiated thymidine pulse. The mean duration of DNA synthesis (tS) was 8 h. The mean duration of the gap phase before appearance of labeled mitoses was 5 h. Whereas the duration of the cell cycle (tC) based on analysis of labeled mitoses was 30 h, the doubling time (tD) derived from cell counts in the same cultures was only about 23 h. The analysis of the indices of labeled nuclei and mitoses suggests a stimulation of cells at the time of pulse labeling, which was maximal after beginning of the gap phase before DNA-synthesis, and possibly caused the observed difference between tC and tD.","PeriodicalId":23706,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete","volume":"26 7","pages":"722-4"},"PeriodicalIF":0.0,"publicationDate":"1971-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1971-0717","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15502470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The significance of isosbestic points and absorbance-difference diagrams for testing the “Einheitlichkeit” (“uniformity”) of a reaction is discussed by use of the imidazole catalysed hydrolysis of p-nitrophenyl acetate as an example. The analysis was based on kinetic spectra E(λ)t1, t2,..., tn and time dependant absorbance values at various wave lengths E (t) λ1, λ2,..., λm measured preferably in the same reaction vessel. The (pseudo-) first-order rate constants were calculated from the absorbance-time curves E(t))λ by formal integration. The kinetic constants of the various reaction steps were used for digital simulation of the total reaction by an electronic computer. The evaluation methods described need neither extinction coefficients nor experimentally determined E∞ values but make it possible to compute them.
{"title":"[Kinetic analysis of model reactions for enzyme catalysis using kinetic spectra, absorbance-difference diagrams and formal integration].","authors":"H Lachmann, H Mauser, F Schneider, H Wenck","doi":"10.1515/znb-1971-0701","DOIUrl":"https://doi.org/10.1515/znb-1971-0701","url":null,"abstract":"The significance of isosbestic points and absorbance-difference diagrams for testing the “Einheitlichkeit” (“uniformity”) of a reaction is discussed by use of the imidazole catalysed hydrolysis of p-nitrophenyl acetate as an example. The analysis was based on kinetic spectra E(λ)t1, t2,..., tn and time dependant absorbance values at various wave lengths E (t) λ1, λ2,..., λm measured preferably in the same reaction vessel. The (pseudo-) first-order rate constants were calculated from the absorbance-time curves E(t))λ by formal integration. The kinetic constants of the various reaction steps were used for digital simulation of the total reaction by an electronic computer. The evaluation methods described need neither extinction coefficients nor experimentally determined E∞ values but make it possible to compute them.","PeriodicalId":23706,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete","volume":"26 7","pages":"629-38"},"PeriodicalIF":0.0,"publicationDate":"1971-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1971-0701","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15502467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The stromata of etioplasts, greening etioplasts, and chloroplasts contain proteins which crossreact with proteins of the lamellar system of chloroplasts. It is shown that at least one cross-reacting protein is a water-soluble precursor of the lamellar system. The water-insoluble fractions of the plastids were dissolved in buffer containing Na-benzene-dodecylsulfonate and analyzed by gel electrophoresis. The disc electrophoresis patterns of the prolamellar bodies of etioplasts showed 8 protein-containing bands of which 7 were also present in the preparations from greening etioplasts. The latter also yielded 5 new protein-containing bands. The lamellar system of chloroplasts showed only 8 bands which were identical with those of greening etioplasts, but it had only 3 bands in common with the prolamellar bodies of the etioplasts. Two of these proteins may be identical with antigens cross-reacting with stroma proteins.
{"title":"[Localization of protein synthesis during development of the lamellar system of greening etioplasts].","authors":"K Lürssen","doi":"10.1515/znb-1971-0718","DOIUrl":"https://doi.org/10.1515/znb-1971-0718","url":null,"abstract":"The stromata of etioplasts, greening etioplasts, and chloroplasts contain proteins which crossreact with proteins of the lamellar system of chloroplasts. It is shown that at least one cross-reacting protein is a water-soluble precursor of the lamellar system. The water-insoluble fractions of the plastids were dissolved in buffer containing Na-benzene-dodecylsulfonate and analyzed by gel electrophoresis. The disc electrophoresis patterns of the prolamellar bodies of etioplasts showed 8 protein-containing bands of which 7 were also present in the preparations from greening etioplasts. The latter also yielded 5 new protein-containing bands. The lamellar system of chloroplasts showed only 8 bands which were identical with those of greening etioplasts, but it had only 3 bands in common with the prolamellar bodies of the etioplasts. Two of these proteins may be identical with antigens cross-reacting with stroma proteins.","PeriodicalId":23706,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete","volume":"26 7","pages":"725-9"},"PeriodicalIF":0.0,"publicationDate":"1971-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1971-0718","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15502471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Chiasm of olfactory axons in the olfactory bulb of catfishes].","authors":"A Holl, E Schulte, W Holl","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":23706,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete","volume":"26 7","pages":"739-40"},"PeriodicalIF":0.0,"publicationDate":"1971-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15502472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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