The bacteriophage 2C, when stored at 4°C loses its biological activity rapidly. It has been observed that the DNA from such inactive phages is also degraded. The preliminary studies indicate that the “heavy” strand of the DNA gets degraded first followed by the “light” strand
{"title":"Loss of biological activity of bacteriophage 2C and degradation of its DNA in storage.","authors":"G Chinnadurai","doi":"10.1515/znb-1972-1213","DOIUrl":"https://doi.org/10.1515/znb-1972-1213","url":null,"abstract":"The bacteriophage 2C, when stored at 4°C loses its biological activity rapidly. It has been observed that the DNA from such inactive phages is also degraded. The preliminary studies indicate that the “heavy” strand of the DNA gets degraded first followed by the “light” strand","PeriodicalId":78857,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B. Anorganische Chemie, organische Chemie, Biochemie, Biophysik, Biologie","volume":"27 12","pages":"1497-500"},"PeriodicalIF":0.0,"publicationDate":"1972-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1972-1213","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15254214","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}
Isolated crayfish retinas were perfused with four solutions in which Li+, ΝΗ4+, Tris H+ and glucose were substituted for the sodium ions in the physiological salt solution. The changes of the extracellularly recorded receptor potential (ReP) evoked by short or long stimuli were measured. The changes in the shape of ReP by test solutions were different for each Na-substitute. For lithium ions as a Na-substitute (Tab. I and Fig. 3) the plateau value he was considerably decreased (to ∼20%) contrary to the peak-amplitude hmax which even slightly increased. Ammonium ions show quite a different effect than all the other substitutes. The ReP is decreased strongly and irreversibly (Tab. II and Fig. 4). When Tris (hydroxymethyl-ammoniummethane-hydrochloride) is substituted for Na, hmax decreased to about 60 per cent and the plateau is even more reduced (to 20 per cent; Tab. III). Only the recovery-value for he (50% smaller) is markedly different contrary to our former experiments where choline was used as Na-substitute (decrease 20%). Glucose as a substitute for sodium chloride caused strongly decreased peak-amplitude hmax 26% (Tab. IV and Fig. 9). Increased osmotic pressure due to excess glucose causes irreversible damage of the ReP (Tab. V). All the changes except those produced by NH4+ were reasonably reversible. The results can be explained by the following assumptions: a) the maximum of the ReP is caused mainly by an increase in the permeability of the cell membrane for sodium. Ca- and Mg-ions also contribute to it to a certain degree. b) The plateau value of the ReP to long light stimuli is determined: 1. by the sodium concentration gradient, 2. by active transport processes, 3. by the Ca++ - and Mg++-gradients, 4. the chloride gradient may perhaps contribute to this value
{"title":"The effect of some sodium substitutes on the receptor potential of the crayfish photoreceptor cell.","authors":"H Stieve, H Gaube, T Malinowska","doi":"10.1515/znb-1972-1219","DOIUrl":"https://doi.org/10.1515/znb-1972-1219","url":null,"abstract":"Isolated crayfish retinas were perfused with four solutions in which Li+, ΝΗ4+, Tris H+ and glucose were substituted for the sodium ions in the physiological salt solution. The changes of the extracellularly recorded receptor potential (ReP) evoked by short or long stimuli were measured. The changes in the shape of ReP by test solutions were different for each Na-substitute. For lithium ions as a Na-substitute (Tab. I and Fig. 3) the plateau value he was considerably decreased (to ∼20%) contrary to the peak-amplitude hmax which even slightly increased. Ammonium ions show quite a different effect than all the other substitutes. The ReP is decreased strongly and irreversibly (Tab. II and Fig. 4). When Tris (hydroxymethyl-ammoniummethane-hydrochloride) is substituted for Na, hmax decreased to about 60 per cent and the plateau is even more reduced (to 20 per cent; Tab. III). Only the recovery-value for he (50% smaller) is markedly different contrary to our former experiments where choline was used as Na-substitute (decrease 20%). Glucose as a substitute for sodium chloride caused strongly decreased peak-amplitude hmax 26% (Tab. IV and Fig. 9). Increased osmotic pressure due to excess glucose causes irreversible damage of the ReP (Tab. V). All the changes except those produced by NH4+ were reasonably reversible. The results can be explained by the following assumptions: a) the maximum of the ReP is caused mainly by an increase in the permeability of the cell membrane for sodium. Ca- and Mg-ions also contribute to it to a certain degree. b) The plateau value of the ReP to long light stimuli is determined: 1. by the sodium concentration gradient, 2. by active transport processes, 3. by the Ca++ - and Mg++-gradients, 4. the chloride gradient may perhaps contribute to this value","PeriodicalId":78857,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B. Anorganische Chemie, organische Chemie, Biochemie, Biophysik, Biologie","volume":"27 12","pages":"1535-46"},"PeriodicalIF":0.0,"publicationDate":"1972-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1972-1219","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15254220","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":"[Bacteria in the macronucleus of Loxophyllum meleagris].","authors":"K Hausmann","doi":"10.1515/znb-1972-1225","DOIUrl":"https://doi.org/10.1515/znb-1972-1225","url":null,"abstract":"","PeriodicalId":78857,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B. Anorganische Chemie, organische Chemie, Biochemie, Biophysik, Biologie","volume":"27 12","pages":"1572"},"PeriodicalIF":0.0,"publicationDate":"1972-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1972-1225","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15254223","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}
This report concerns the ultraviolet absorption and optical rotatory dispersion (ORD) of DNA and of nucleotides down to 185 mμ. An absorption band (y) at about 195 mμ occurs for all these compounds. Similar studies have been made on histones and nucleohistone. These indicate a strong absorption below 200 mμ due to protein. Consequently, if any native DNA is associated with some amount (2 - 12%) of protein (e.g., histones), the molecular absorption of DNA in the said region becomes masked, and no clear y-maximum due to DNA occurs in the absorption spectrum. The absorption of DNA in the y-band region (ca. 190 mμ) seems to be decreased as a result of DNA-protein interaction. No significant change is observed in the absorption region of DNA at longer wavelengths (250-290 mμ). The y-peak of DNA appears at about 190 mμ on complete removal of proteins. This peak is sharper than the conventional one (x) at 260 mμ and is hyperchromic on denaturation, and involves multiple Cotton effects to any degrees similar to that observed at the second peak (260 mμ). The absorption (also ORD) features of nucleohistone at the x and y wavelengths do not provide similar information (e.g., denaturation artefacts) regarding the structure of the nucleohistone contained DNA which is apparently distinct from the structures of native and partially denatured (denaturation 10%) DNA. The weaker π-π* transition (190 mμ) in the DNA bases is very susceptible to nucleoprotein interaction. This result has been used to explain the influence of nucleoprotein interaction on the configuration of DNA in nucleohistone
{"title":"Ultraviolet absorption and optical rotatory dispersion studies of deoxyribonucleic acid and nucleohistone.","authors":"S Basu","doi":"10.1515/znb-1972-1216","DOIUrl":"https://doi.org/10.1515/znb-1972-1216","url":null,"abstract":"This report concerns the ultraviolet absorption and optical rotatory dispersion (ORD) of DNA and of nucleotides down to 185 mμ. An absorption band (y) at about 195 mμ occurs for all these compounds. Similar studies have been made on histones and nucleohistone. These indicate a strong absorption below 200 mμ due to protein. Consequently, if any native DNA is associated with some amount (2 - 12%) of protein (e.g., histones), the molecular absorption of DNA in the said region becomes masked, and no clear y-maximum due to DNA occurs in the absorption spectrum. The absorption of DNA in the y-band region (ca. 190 mμ) seems to be decreased as a result of DNA-protein interaction. No significant change is observed in the absorption region of DNA at longer wavelengths (250-290 mμ). The y-peak of DNA appears at about 190 mμ on complete removal of proteins. This peak is sharper than the conventional one (x) at 260 mμ and is hyperchromic on denaturation, and involves multiple Cotton effects to any degrees similar to that observed at the second peak (260 mμ). The absorption (also ORD) features of nucleohistone at the x and y wavelengths do not provide similar information (e.g., denaturation artefacts) regarding the structure of the nucleohistone contained DNA which is apparently distinct from the structures of native and partially denatured (denaturation 10%) DNA. The weaker π-π* transition (190 mμ) in the DNA bases is very susceptible to nucleoprotein interaction. This result has been used to explain the influence of nucleoprotein interaction on the configuration of DNA in nucleohistone","PeriodicalId":78857,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B. Anorganische Chemie, organische Chemie, Biochemie, Biophysik, Biologie","volume":"27 12","pages":"1516-28"},"PeriodicalIF":0.0,"publicationDate":"1972-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1972-1216","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15254217","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}
Normal embryonic rat cells, which are synchronized in G1 phase of their cell cycle, by incubation in serum-free medium contain a DNA fraction with a sedimentation coefficient S20 between 11 and 12. This double-stranded DNA shows a significantly higher buoyant density in caesiumchloride than does the bulk of cellular DNA, and its replication is not restricted to a distinct part of the S period. The possible role of these DNA subunits in the replication mechanism is discussed
{"title":"[Properties of a low-molecular weight DNA from embryonic rat cells in culture].","authors":"R Manso-Martinez, W Frank","doi":"10.1515/znb-1972-1215","DOIUrl":"https://doi.org/10.1515/znb-1972-1215","url":null,"abstract":"Normal embryonic rat cells, which are synchronized in G1 phase of their cell cycle, by incubation in serum-free medium contain a DNA fraction with a sedimentation coefficient S20 between 11 and 12. This double-stranded DNA shows a significantly higher buoyant density in caesiumchloride than does the bulk of cellular DNA, and its replication is not restricted to a distinct part of the S period. The possible role of these DNA subunits in the replication mechanism is discussed","PeriodicalId":78857,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B. Anorganische Chemie, organische Chemie, Biochemie, Biophysik, Biologie","volume":"27 12","pages":"1507-15"},"PeriodicalIF":0.0,"publicationDate":"1972-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1972-1215","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15254216","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":"n-Paraffins from flowers of L. umbellata Thumb.","authors":"N Hayashi, H Komae","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":78857,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B. Anorganische Chemie, organische Chemie, Biochemie, Biophysik, Biologie","volume":"27 11","pages":"1438"},"PeriodicalIF":0.0,"publicationDate":"1972-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15512318","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}
It is demonstrated that the 220—225 nm Cotton effect of 4-nitro imidazole nucleosides can be used for the determination of the configuration of this class of compounds. A more detailed picture about conformation and configuration of the sugar residue is received from the copperammonia complexes of these nucleosides. The pH-dependency of the stability and the complex ratio are discussed for a furanose moiety. Correlation between signs and intensities of the Cotton effects and configurations and conformations of the diol structures are discussed.
{"title":"[Investigations on the configuration of 4-nitro imidazole nucleosides].","authors":"H Vergin, H Bauer, G Kuhfittig, W Voelter","doi":"10.1515/znb-1972-1119","DOIUrl":"https://doi.org/10.1515/znb-1972-1119","url":null,"abstract":"It is demonstrated that the 220—225 nm Cotton effect of 4-nitro imidazole nucleosides can be used for the determination of the configuration of this class of compounds. A more detailed picture about conformation and configuration of the sugar residue is received from the copperammonia complexes of these nucleosides. The pH-dependency of the stability and the complex ratio are discussed for a furanose moiety. Correlation between signs and intensities of the Cotton effects and configurations and conformations of the diol structures are discussed.","PeriodicalId":78857,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B. Anorganische Chemie, organische Chemie, Biochemie, Biophysik, Biologie","volume":"27 11","pages":"1378-85"},"PeriodicalIF":0.0,"publicationDate":"1972-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1972-1119","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15512310","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 stability constants of the ternary Cu2+ complexes containing adenosine 5′-monophosphate (AMP) and as a second ligand, 2,2′-bipyridyl, 4- (2′-pyridyl) imidazole, 2-picolylamine, 4-aminomethylimidazole, and ethylenediamine were determined by potentiometric titration in water containing 10% dioxane (I=0.1; 25°C). For the equilibrium, Cu (amine) 2++Cu (AMP) ⇄Cu (amine) (AMP) +Cu2+, the corresponding constants are (in the order of the above amine ligands), Δ log K =log =0.53, 0.20, 0.04, —0.35, and—0.45; hence, inthefirst cases the equilibrium is considerably on the side of the mixed-ligand complex. The importance of the π-system of the amine for the stability of the mixed-ligand Cu2+ complexes is obvious from the given series. The imidazole group, an important binding site for metal ions in biological systems, has clearly qualities similar to the pyridyl group (Inorg. Chem. 9, 1238 [1970]), i. e. the stability of ternary Cu2+ complexes containing these groups is increased.
{"title":"Ternary complexes in solution. XIV. The stability increasing effect of the pyridyl and imidazole groups on the formation of mixed amine-copper(II)-adenosine 5'-monophosphate complexes.","authors":"P R Huber, H Sigel","doi":"10.1515/znb-1972-1107","DOIUrl":"https://doi.org/10.1515/znb-1972-1107","url":null,"abstract":"The stability constants of the ternary Cu2+ complexes containing adenosine 5′-monophosphate (AMP) and as a second ligand, 2,2′-bipyridyl, 4- (2′-pyridyl) imidazole, 2-picolylamine, 4-aminomethylimidazole, and ethylenediamine were determined by potentiometric titration in water containing 10% dioxane (I=0.1; 25°C). For the equilibrium, Cu (amine) 2++Cu (AMP) ⇄Cu (amine) (AMP) +Cu2+, the corresponding constants are (in the order of the above amine ligands), Δ log K =log =0.53, 0.20, 0.04, —0.35, and—0.45; hence, inthefirst cases the equilibrium is considerably on the side of the mixed-ligand complex. The importance of the π-system of the amine for the stability of the mixed-ligand Cu2+ complexes is obvious from the given series. The imidazole group, an important binding site for metal ions in biological systems, has clearly qualities similar to the pyridyl group (Inorg. Chem. 9, 1238 [1970]), i. e. the stability of ternary Cu2+ complexes containing these groups is increased.","PeriodicalId":78857,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B. Anorganische Chemie, organische Chemie, Biochemie, Biophysik, Biologie","volume":"27 11","pages":"1319-23"},"PeriodicalIF":0.0,"publicationDate":"1972-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/znb-1972-1107","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15512304","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":"[Kinetic analysis of photochemical reactions using extinction diagrams. II. The photochemical consecutive reaction of anthraquinone in alkaline methanol].","authors":"H Mauser, V Starrock, H J Niemann","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":78857,"journal":{"name":"Zeitschrift fur Naturforschung. Teil B. Anorganische Chemie, organische Chemie, Biochemie, Biophysik, Biologie","volume":"27 11","pages":"1354-9"},"PeriodicalIF":0.0,"publicationDate":"1972-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15512306","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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