Isoforms of baker's yeast transketolase

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Tetrapyrrole biosynthesis from 4,5-dioxovaleric acid inRhodopseudomonas spheroides

Summary Porphyrin biosynthesis from 4,5-dioxovaleric acid was studied in cell suspensions ofR. spheroides. The experiments show that 4,5-dioxovaleric acid is a far precursor of porphyrins through amino laevulinic acid formation in a transamination reaction involving also 1-alanine. It differs radically from the classical aminolaevulinic acid synthesis using glycine and succinyl CoA as substrates.Acknowledgments: The authors are indebted to Dr Rodolfo García for helpful discussions and criticisms. Special thanks are given to Dr Aldo Mitta and other members of the Comisión Nacional de la Energía Atómica for their continuous help and support and for using their facilities in order to synthetise DVA.     

Down's syndrome: permeability of the erythrocyte membrane for spin-labeled non-electrolytes

Summary A decreased rate of membrane transport of a hydrophobic non-electrolyte TEMPO was found. There were no significant changes in that of a hydrophilic non-electrolyte TEMPOL in erythrocytes of patients with trisomy 21. Changes of the same direction in erythrocyte membrane permeability were found to occur during the intravascular erythrocyte aging.We are indebted to Dr K. Gwodziski for the gift of spin labels synthesized by him and methodical advice.     

Improved method for preparation of microcrystalline chlorophyll a withAnacystis nidulans as a source

Summary Because of the lack of chlorophyll b, blue-gree algae are a better source of microcrystalline, high-purity chlorophyll a than the spinach leaves so far used. The preparation is easy and rapid, and the danger of chemical alteration of the chlorophyll is reduced.Acknowledgments. I thank Prof. E. Broda for his interest and Prof. H. Falk for valuable advice. I am also indebted to Mr E. Maday (IR spectography), Dr J. Seifert (X-ray) and Dr H. Zak (elemental analysis.). The work was supported by the Fonds zur Förderung der wissenschaftlichen Forschung of the Republic of Austria.     

Chromosomes and giemsa-bands of the Idaho spotted ground squirrel,Spermophilus brunneus (Howell)

-Spermophilus brunneus . , 13 18 ,S. brunneus S. townsendii mollis (2n=38) , , ; ;S. brunneus . S. brunneus , Spermophilus.

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Supported by National Science Foundation Grants No. GB32114X and No. GB 29131X, and the Sprague Foundation. We thankD. Pozin for technical assistance.     

Deuterium isotope effects in the ninhydrin reaction of primary amines

Summary The rate of development of Ruhemann's purple in the ninhydrin reaction of two deuterated primary amines, -d₂-p-tyramine and -d₂--phenylethylamine, is significantly reduced It appears to be a primary isotope effect and indicates that the cleavage of the carbon-hydrogen bond at the -position is involved in the rate-determining step of the color reaction.Acknowledgements. We thank Dr A.A. Boulton for his advice and encouragement and the Canadian Medical Research Councel and Saskatchewan Health for their continuing financial support.     

The role of the pentose-phosphate pathway in adjustment of the heart to a high load and the development of myocardial hypertrophy

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Mass spectrometric determination of the amino acid sequence in peptides: Desulfurization of sulfur-containing peptides

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Magnetitfördernde Wirkung von Al3+-Ionen bei der Luftoxidation des Fe(OH)2

Summary It has been proved that Fe(OH)₂, precipitated in alkaline solution and oxidated by air-oxygen, transforms to -FeOOH. In presence of A1³⁺, besides -FeOOH magnetite also appears.     

Thymus stimulation and cancer prophylaxis byViscum proteins

Zusammenfassung Die cancerostatischen Viscum-Proteine induzieren im Tierversuch mit geringsten Dosen eine Proliferation des Thymus und verhindern prophylaktisch das Angehen von Tumoren. Höhere Dosen zerstören dagegen den Immunapparat durch Überbeanspruchung und die Tumorhemmung bleibt aus.

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We are indebted to the Deutsche Forschungsgemeinschaft for financial support (M. St.) and for granting a Forschungsfreijahr (F. V.).     

IdentifyingY chromosome in interphase nuclei of the human brain

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Metabolism of a pharmacologically active pyrrolidine derivative (prolintane) by lactam formation

Zusammenfassung Prolintan, N-1-(-Benzylbutyl)-Pyrrolidin, wurde in Kaninchen durch ein Mikrosomensystem der Leber in das entsprechende Laktam, N-1-(-Benzylbutyl)-Pyrrolidin-2-on, umgebaut. Das gleiche Stoffwechselprodukt fand sich auch im Gewebe von Ratten, denen das Medikament gegeben wurde; allenfalls Spuren davon wurden im Urin der Ratten ausgeschieden.

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We thank Dr.D. C. Remy for a sample of syntheticdl-1-(-propylphenethyl)-pyrrolidin-2-one.     

Ontogenic development and anatomical distribution of a supernumerary limb-inducing factor

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This work was supported by a Rackham Grant from the University of Michigan.     

Free radicals and aflatoxin biosynthesis

Summary The addition of some halogenated alkanes (bromotrichloromethane, carbontetrachloride and chloroform) to cultures ofA. parasiticus andA. flavus have shown a high stimulating effect on aflatoxin biosynthesis. When the production of aflatoxin increases during the stimulating effect the peroxidase activity is inhibited.Acknowledgments. Supported by Cassa di Risparmio di Roma, funds from Ministry of Education and Faculty of Science of La Sapienza Rome University.     

Circadian periodicity in termination of photorefractoriness in the yellow-throated sparrow

Summary Photorefractory male yellow-throated sparrows (Gymnorhis xanthocollis) were subjected to six resonance light cycles, consisting of 6 h basic photophase coupled with scotophases of longer durations (in cycles of 12 (6L6D) h, 24 (6L18D) h, 36 (6L30D) h, 48 (6L42D) h, 60 (6L54D) h and 72 (6L66D) h). Termination of photorefractoriness was evident in cycles of 24, 48 and 72 h, but not in 12, 36 and 60 h. The results are consistent with the external-coincidence model (Bünning hypothesis) and suggest that endogenous circadian rhythmicity is involved in the termination of photorefractoriness.To whom reprint requests should be addressed.This investigation was supported by a UGC grant to PDT and BHU to PMT.     

Volatiles associated with scolytus scolytus beetles on English elm

Summary -Multistriatin, 4-methyl-3-heptanol and-cubebene, the components of the aggregation pheromone of Scolytus multistriatus are also associated with virgin female Scolytus scolytus on English elm, Ulmus procera.We thank Dr J. F. Grove for advice and encouragement, Mrs J. Allsop for technical assistance, Dr J. W. Peacock for authentic samples of multistriatin, 4-methyl-3-heptanol and-cubebene, and the Parks and Gardens Dept., Brighton Corporation, for supplies of English elm.     

Über das Vorkommen verschieden substituierter Chalkone während der Mikrosporogenese beiTulipa

Summary During the development of anthers inTulipa cv. Apeldoorn the following chalcones were isolated: 2, 3, 4, 4, 6-pentahydroxychalcone as the main component and 2, 4, 4, 6-tetrahydroxy-3-methoxychalcone as well as 2, 4, 4, 6-tetrahydroxychalcone in a very small amount.

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Die Untersuchungen wurden mit Mitteln der Deutschen Forschungsgemeinschaft unterstützt.     

Alteration of early T lymphocyte count in patients with herpes genitalis

Summary Peripheral blood samples from 52 women, including 16 with herpes genitalis and 36 healthy persons, were studied to enumerate subpopulations of lymphocytes. It was found that the mean percentage of active T lymphocytes was significantly less in the patients with herpes genitalis than in the controls.Acknowledgment. This work was done at the Department of Obstetrics and Gynecology, Kansai Medical University and the authors are indebted to Professor I. Sawaragi for his support and encouragement. We also express our thanks to Dr James Monthony, Bio Rad Laboratories for his generous donation of immunobeads for this study.     

A new partial synthesis of holaphyllamine

Résumé L'holaphyllamine peut être aisément préparée à partir du 3, 6-ditosyloxy-5-pregnan-20-one par réaction avec NaN₃.