D-aspartate oxidase activity and D-aspartate content in a mutant mouse strain lacking D-amino acid oxidase

A mutant mouse strain ddY/DAO- lacks D-amino acid oxidase activity and accumulates free neutral D-amino acids in its tissues. In this study, D-aspartate oxidase activity and D-aspartate content in the tissues of these mutant mice were compared with those of normal mice. No significant difference was observed, indicating that the metabolism of acidic D-amino acids was unaffected in the mutant.     

D-Aspartate oxidase activity and D-aspartate content in a mutant mouse strain lacking D-amino acid oxidase

Summary A mutant mouse strain ddY/DAO^– lacks D-amino acid oxidase activity and accumulates free neutral D-amino acids in its tissues. In this study, D-aspartate oxidase activity and D-aspartate content in the tissues of these mutant mice were compared with those of normal mice. No significant difference was observed, indicating that the metabolism of acidic D-amino acids was unaffected in the mutant.     

The behavioral development of the mutant "staggerer" mouse]

The behavioural study, in particular rearing environmental conditions, of the mutant mouse staggerer has shown that such animals may live more than 90 days. (he behavioural diagnosis of this mutation has been possible from the second week of life, using specific tests. A typical "bat posture" permits one to recognize the mutant from the normal Mouse. Locomotory and feeding behaviours also present late and various qualitatige particularities.     

Protein kinase activity in Escherichia coli]

When growing E. coli in a minimal medium, at least four proteins from the soluble fraction and one ribosome-associated protein are found phosphorylated at the level of their threonine and serine residues.     

Comparison of exogenous cell fusion induced by a wild and two mutant strains of sheep Visna virus]

Exogen cell fusion induced in vitro by a wild strain of Visna virus of Sheep is compared with two mutant strains isolated from the precedent. One of them produces large plaques in vitro (strain LPF), and the other produces small plaques (strain SPF). These strains behave in different ways according to infection multiplicity, type of cells, temperature and timing of fusing activity. Taking the wild strain K 796 as a base of reference, the strain SPF seems to have a higher rate fusing activity and the strain LPF lower rate of fusing activity.     

Detection and localization of a ribonuclease activity associated with vaccinia virus]

A ribonuclease associated with vaccinia virus can be detected when reduced concentrations of nucleotides are used for an in vitro RNA synthesis assay. The non-viral origin of this ribonuclease may be inferred from its external location and from its variable activity on different purified virus stocks. The detection of this ribonuclease activity on purified virus grown without foetal Calf serum may suggest that this enzyme is of cellular origin.     

Placing the activity rhythm in Araneus cornutus]

Araneus cornutus spiderling activities recorded from hatching to scattering show a particular distribution of the general motor activity over a 24-hour period. More motor activity is first observed during the light sequence, while at a nocturnal activity distribution appears after the 2nd nymphean ecdysis.     

Electrical colonic activity in the conscious dog]

Identification of two distinct rhythms of the colonic slow waves at a mean frequency of 5 and 18 cycles/min. Evidence is provided for an origin of the faster rhythm from the mascularis mucosae.     

Lewis blood group activity in Fasciola hepatica]

Lewis blood group specificities are detected in the liver Fluke: Fasciola hepatica. Such specificities had never been reported in nature, other than in the human body. The investigation of this phenomenon might contribute to a better understanding of the mechanisms involved in parasite-host relationship.     

Lipoxygenase activity of wheat seeding chloroplasts]

Chloroplasts have been isolated from Wheat shoots by density gradient centrifugation. When added to a linoleic acid and Tween 20 suspension these chloroplasts induce an oxygen consumption. The hydroperoxides synthesized from linoleic and oxygen have been characterized by spectrophotometry and thin layer chromatography.     

Evidence of protein kinase activity in 2 murine oncornaviruses]

A protein kinase activity has been detected in two strains of murine Oncornaviruses, MSV/MLV and EFV. This activity phosphorylates not only endogenous viral proteins but also exogenous substrates (histones and phosvitin). The stimulation of enzyme activity by detergents along with the increase of specific activity in viruses treated with trypsin during purification suggest that the enzyme is located in the viral particle.     

Cure of osteopetrosis by allogenic bone marrow injection in the double mutant "osteopetrosi-athymic" rat]

The cure of osteopetrosis by allogenic bone marrow injection has been obtained in homozygous rats for both mutations, osteopetrosis (op) and athymic nude (rnu). This new animal model will help in studying the eventual relationship between the bone resorption process and the immunological reconstitution.     

Alpha-mannosidase activity of different human biological fluids]

Two distinct alpha-mannosidases have been found in biological fluids by investigating the effect of pH on activity, the effect of Co2+ and Zn2+ and by determining the Michaelis constant. The two enzymes are designated as S, predominating in serum (optimum pH about 5.6) and U, predominating in urine (optimum pH about 4.2). In cerebro-spinal fluid, the amount of alpha-mannosidase S is almost the same as that of alpha-mannosidase U. Alpha-mannosidase S activity in sera is significantly higher in children than in adults.