On the mechanism of spore germination inB. subtilis. Permeability and germination by pyruvate

Riassunto È stata studiata la permeabilità delle spore bacteriche al piruvato. Il piruvato penetra nelle spore soltanto a pH basso, quando la molecola del chetoacido ed i gruppi polari della superficie delle spore sono largamente indissociati. Le modificazioni della superficie, che si verificano nel corso della esposizione a pH acido, non hanno alcuna importanza nel fenomeno. Questi risultati sono messi in relazione con il fatto che il piruvato induce germinazione delle spore soltanto a pH basso e contribuiscono all'ipotesi che un agente germinante, per essere attivo, deve penetrare nella spora ed attivare i sistemi enzimatici quiescenti.     

Inverse regulation of spore germination and growth by cyclic AMP inStreptomyces hygroscopicus

Summary The cyclic AMP level in germinating spores ofStreptomyces hygroscopicus rises to a maximum at outgrowth of germ tubes. Exogenous cyclic AMP results in an inverse effect on germination speed and growth.     

A medium to demonstrate the ligninolytic activity of some fungi

Zusammenfassung Es wird hier eine neue Methode angeführt, um die holzauflösende Fähigkeit einiger Pilze zu bestimmen. Ein milchiges, homogenes Agarmedium wird hergestellt, indem man kugelgemahlenes Buchensägemehl als hauptsächliche Kohlenstoffquelle benutzt. Wenn man in dieses Medium bestimmte holzzerstörende Pilze einpflanzt, wird sowohl ihre holzspaltende als auch ihre zellulosezerstörende Wirkung dadurch gezeigt, dass das Medium unter dem Wurzelgeflecht sich aufklärt.     

On the antitumour activity of some poducts of wood-decaying fungi

Zusammenfassung Die Versuchsergebnisse über die antitumoröse Aktivität einiger holzzerstörender Pilze (Lösung des roten Pigmentes nachSchánl ⁴) wurde beschrieben. Das Überleben von Mäusen mit implantiertem Ehrlich'schem Karzinom ist statistisch in der Gruppe der behandelten Tiere in 5% gesichert. Histologisch ist es bei länger behandelten und überlebenden Tieren zum Verschwinden des karzinomatösen Charakters gekommen, und an seiner Stelle bildete sich ein pleiomorföses Sarkom.     

IAA oxidase activity in relation to adventitious root formation on stem cuttings of some forest tree species

Summary IAA oxixase activity was very high in stem cuttings ofSalix tetrasperma andPopulus robusta, which rooted profusely, less in stem cuttings ofHibiscus rosa sinensis which rooted less, and insignificant in those ofEucalyptus citriodora which did not root at all. Protein(s) extracted from the stem cuttings ofE. citriodora inhibited the activity of IAA oxidase as well as root formation on hypocotyl cuttings ofPhaseolus mungo. The possibility of involvement of IAA oxidase activity in the process of adventitious root formation is discussed.The research has been financed by a grant from U.S. Department of Agriculture.     

Circadian rhythmycity of some key metabolites in the fasted and fed weanling female rat

Zusammenfassung Bei je 32 Ratten im Hungerzustand und mit normaler Fütterung wurden Tagesschwankungen von Na, K, Protein, Harnstoff, Phosphor und Glukose im Serum gefunden. Die Schwankungen spiegeln zweifellos die Aktivität mehrerer endokriner Sekretionen wider, welche wiederum von der Biologischen Uhr⁸ beeinflusst werden.

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This investigation was supported by U.S.P.H.S. Grant No. HE 06975 from the National Heart Institute.     

Effect of fungal staling growth products on colony interaction amongRhizoctonia solani Kuhn and some potential rhizosphere fungi

Summary Colony interactions betweenRhizoctonia solani Kuhn: a root pathogen ofLycopersicon esculentum Mill and some dominant rhizosphere fungi were assessed in vitro in virgin and staled agar to examine their antagonistic ability and tolerance to antagonism. The range of inhibition ofR. solani varied widely in competition with some of the antagonists.Acknowledgments. I would like to express my appreciation to Dr R. S. Dwivedi for encouragement and CSIR for financial assistance.Address for reprint request: Dr D.K. Arora, Old G/14, Jodhpur Colony, Banaras Hindu University, Varanasi 221005, India.     

Ovarian serotonin content in relation to ovulation

Summary In the mature cyclic female rat, analysis for ovarian serotonin content reveals comparatively high serotonin content. Fluctuation of serotonin content was observed; peak for serotonin was observed at estrus. In gonadotropintreated immature rats, there was no detected ovarian serotonin using this procedure. It was concluded that ovaries from gonadotropin-treated immature rats are physiologically different from ovaries taken from mature cyclic rats.Supported by NIH Grant RR8111.National Institutes of Health, MBS Trainee.     

Aging in relation to auxin and RNA

Résumé Sur des extraits de racine deLens culinaris, il est observé qu'au cours du vieillissement cellulaire les enzymes qui contrôlent le catabolisme auxinique sont progressivement plus actives, ce qui a pour conséquence d'entraîner une diminution du taux en auxines endogènes. Par ailleurs, l'activité des systèmes RNasiques — inhibés par les auxines — va s'élever d'une façon significative dans les cellules âgées ce qui explique, partiellement du moins, la diminution de le teneur en RNA.