Electrical Properties and Ultrastructure of Mycoplasma Membranes

Mycoplasma, in particular species laidlawii and gallisepticum, are found to have a very small, low frequency conductivity as would be predicted by the dielectric model for bacteria and their apparent lack of cell wall structure. Membrane capacitance values for the two organisms are both about 0.9 μF/cm², although electron micrographs show that the membrane of M. gallisepticum is 20-40 A thicker than that of M. laidlawii.     

Variations des activités peroxydasique et phénoloxydasique au cours de la croissance de Coleus blumei Benth. var. Automne

Summary The specific peroxidase (1.11.1.7) and phenoloxidase (1.10.3.1) activities are quantitatively measured during the life of Coleus, from germination until flowering. In most organs investigated, the peroxidase activity increases rapidly with growth while the phenoloxidase activity remains low. The latter activity is higher in root apices than in more differentiated regions of roots. From the results obtained it may be concluded that the phenoloxidase activity accompanies cellular proliferation. It is suggested that the peroxidase activity plays an indirect role in root initiation through its role in cellular differentiation.

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Extrait d'une thèse de doctorat soutenue à la Faculté des Sciences de l'Université de Liège.     

Change in Properties of Physarum polycephalum Amoebae During Extended Culture

During two years of passage, several myxamoebal strains of Physarum polycephalum changed with regard to their properties in crosses and plaque morphology. These changes have been correlated with increased nuclear deoxyribonucleic acid content.     

The isolation of cholest-5-ene-3β,26-diol from human brain (Short Communication)

Cholest-5-ene-3beta,26-diol, isolated from human brain, was further characterized by oxidation to 3-oxocholest-4-en-26-ol and to 3-oxocholest-4-en-26-oic acid. Identification was achieved by comparison (by t.l.c., g.l.c. and g.l.c.-mass spectrometry) with corresponding reference compounds derived from kryptogenin.     

Carnitine and trimethylaminobutyrate synthesis in rat tissues (Short Communication)

Liver and testis slices convert 6-N-trimethyl-lysine into 4-N-trimethylaminobutyrate and carnitine. Adipose, skeletal muscle, heart, or kidney tissues metabolize trimethyl-lysine into trimethylaminobutyrate but not into carnitine. Trimethylaminobutyrate hydroxylation, forming carnitine, occurs in liver and to a minor degree in testis. Liver is the primary site of carnitine biosynthesis in the rat.