Alkaloids of Papaver bracteatum: 14-β-hydroxycodeinone, 14-β-hydroxycodeine and N-methylcorydaldine

Three new alkaloids have been identified from Papaver bracteatum, 14-β-hydroxycodeinone, 14-β-hydroxycodeine and N-methylcorydaldine. The presence of alpinigenine was also confirmed.     

Protection of foreign DNA against host-controlled restriction in bacterial cells

Summary Foreign Flac plasmid DNA which is introduced into potentially restricting E. coli recipient cells can be protected from restriction by preinfecting the recipient cells with UV-inactivated T3 or T7 bacteriophages which express the ocr gene function. The recipient cells survive and are able to replicate themselves as well as the newly acquired plasmid.     

Composition of a Photosystem I chlorophyll protein complex from Anabaena flos-aquae

The use of Triton X-100 to solubilize membrane fragments from Anabaena flos-aquae in conjunction with DEAE cellulose chromatography allows the separation of three green fractions. Fraction 1 is detergent-solubilized chlorophyll, and Fraction 2 contains one polypeptide in the 15 kdalton area. Fraction 3, which contains most of the chlorophyll and shows P-700 and photosystem I activity, shows by SDS gel electrophoresis varying polypeptide profiles which reflect the presence of four fundamental bands as well as varying amounts of other polypeptides which appear to be aggregates containing the 15 kdalton polypeptide. The four fundamental bands are designated Band I at 120, Band II at 52, Band III at 46, and Band IV at 15 kdaltons. Band I obtained using 0.1% SDS contains chlorophyll and P-700 associated with it. When this band is cut out and rerun, the 120 kdalton band is lost, but significant increases occur in the intensities of Bands II, III, and IV as well as other polypeptides in the 20–30 kdalton range.The use of 1% Triton X-100 coupled with sucrose density gradient centrifugation allows the separation of three green bands at 10, 25 and 40% sucrose. The 10% layer contains a major polypeptide which appears to be Band IV. The 25 and 40% layers show essentially similar polypeptide profiles, resembling Fraction 3 in this regard, except that the 40% layer shows a marked decrease in Band III. Treatment of the material layering at the 40% sucrose level with a higher (4%) concentration of Triton X-100 causes a loss (disaggregation) of the polypeptides occurring in the 60–80 kdalton region and an increase in the lower molecular weight polypeptides. Thus, aggregation of the lower molecular weight polypeptides accounts for the variability seen in the electrophoresis patterns. Possible relations of the principal polypeptides to the known photochemical functions in the original membrane are discussed.     

Evidence for a phospholipid requirement of chitin synthase inSchizophyllum commune

Evidence for a lipid dependence of membrane-associated chitin synthase inSchizophyllum commune is based on the following observations: Arrhenius plots of the temperature dependence of this enzyme showed deflections from linearity that are characteristic for lipid-affected membrane-bound enzymes. The activity of chitin synthase dissociated by digitonin decreased at increasing digitonin/protein ratios and could be restored by addition of egg lecithin. After further delipification by sucrose gradient centrifugation, enzyme activity progressively decreased, banded at higher densities, and was less effectively restored by lecithin. The activity of dissociated chitin synthase was also restored by soybean phosphatidylcholine and low concentrations of phosphatidylinositol and phosphatidylserine. At higher concentrations, phosphatidylinositol and phosphatidylserine were inhibitory. Lysophosphatidylcholine and phosphatidylethanolamine were slightly stimulatory, whereas no effect resulting from ergosterol was observed.     

Fledgling production of EidersSomateria mollissima in The Netherlands

Summary For 28 years, the survival up to fledging of Eider ducklings has been determined in the Dutch colony on Vlieland. On average 0.342 (0.001–1.528) ducklings per female fledged yearly. Within the ranges observed, the total number of ducklings that fledged seemed to be independent of the number of breeding females (range 800–2700) and the number of Herring Gulls in the study period. Indications were found of a sex-linked mortality occurring in some years. Correlations with a number of environmental factors suggested that low temperature in winter, high temperature at the end of May and the beginning of June, calm weather in May and June, and a high number of Herring Gulls were profitable for fledgling success. However, a stepwise multiple regression indicated only the temperature at the beginning of June as significant, explaining about 18 % of the total variance. The absence of a negative relation with breeding gull numbers confirms the interpretation of the role of the Herring Gull as a secondary mortality factor. Experiments showed that Goose Virus Hepatitis (syn. Goose Influenza or Goose Pest) was a primary cause of mortality among ducklings older than one week. The effect of diseases in the field was difficult to establish as diseased and weakened ducklings were usually eaten by gulls. A long-lasting fledgling failure was recorded from 1966 up to and including 1977. In the same period changes were noted in the biological systems in the North Sea.

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Zusammenfassung In einer Eiderenten-Kolonie auf der holländischen Insel Vlieland wurden die Überlebensraten der Küken 28 Jahre lang erfaßt. Im Mittel wurden jährlich 0.342 (0.001–1.528) Küken pro Weibchen flügge. Die Gesamtzahl der Küken war offensichtlich von der Anzahl brütender Weibchen (800–2700) sowie der Anzahl der Silbermöwen unabhängig. In einigen Jahren gab es Anzeichen für eine geschlechtsabhängige Sterblichkeit. Beziehungen zwischen der Rate flügger Jungvögel und einigen Umweltparametern, wie niedriger Temperatur im Winter, hoher Temperatur Ende Mai bis Anfang Juni, windarmes Wetter im Mai und Juni sowie der Präsenz vieler Silbermöwen ließen sich aufzeigen. Eine stufenweise multiple Regression zeigte jedoch, daß nur die Temperatur Anfang Juni einen signifikanten Einfluß hatte. Das Fehlen einer negativen Korrelation mit der Anzahl brütendee Möwen stützt die Annahme, daß die Rolle dere Silbermöwe als zweitrangig einzustufen ist. Versuche belegten, daß der Virus der Gänsehepatitis die Sterblichkeit von mindestens eine Woche alten Kücken unmittelbar bestimmte. Der Einfluß von Krankheiten konnte im Feld nur bedingt festgestellt werden, weil Möwen kranke und geschwächte Kücken üblicherweise fressen. Ein anhaltender Tiefstand des Aufzuchterfolges von 1966 bis 1977 fiel zeitlich mit allgemeinen Veränderungen der biologischen Verhältnisse der Nordsee zusammen.

     

Analysis of pipecolic acid in biological fluids using capillary gas chromatography with electron-capture detection and [H11]pipecolic acid as internal standard

A sensitive and accurate stable isotope dilution assay was developed for the measurement of pipecolic acid in body fluids using capillary gas chromatography with electron-capture detection. The method utilizes [²H₁₁]pipecolic acid as the internal standard. Sample preparation consisted of derivatization in aqueous solution (pH 11.5) of the amine moiety with methyl chloroformate to the N-methylcarbamate, followed by acidic ethyl acetate extraction at pH ≤ 2 and further derivatization of the carboxyl moiety with pentafluorobenzyl bromide, the excess of which was removed by solid-phase extraction. Control values have been determined in the plasma of at-term infants, age > 1 week (n = 21, mean = 1.36 μM, range = 0.47–3.27 μM). The utility of the method was demonstrated by quantitating pipecolic acid in biological fluids derived from patients with peroxisomal disorders. The method was validated against an established electron-capture negative ion mass fragmentographic technique.     

Competitive membrane adsorption of Na+, K+, and Ca2+ in smooth muscle cells

Summary A theory for Na⁺, K⁺ and Ca²⁺ competitive adsorption to a charged membrane is used to explain a number of experimental observations in smooth muscle. Adsorption is described by Langmuir isotherms for mono- and divalent cations which in turn are coupled in a self-consistent way to the bulk solution through the diffuse double layer theory and the Boltzman equations. We found that the dissociation constants for binding of Na⁺, K⁺ and Ca²⁺ in guinea pig taenia coli areca. 0.009, 1.0, and 4×10^–8 m, respectively. Furthermore, the effect of a Ca²⁺ pump that maintains free surface Ca²⁺ concentration constant is investigated. A decrease in intracellular Na⁺ content results in an increased Ca²⁺ uptake; part of this uptake is due to an increase in surface-bound Ca²⁺ in an intracellular compartment which is in contact with the myofilaments. Variations in the amount of charge available to bind Ca²⁺ and the surface charge density are studied and their effect interpreted in terms of different pharmacological agents.