D-Aspartate oxidase and D-amino acid oxidase are localised in the peroxisomes of terrestrial gastropods

D-Aspartate oxidase and D-amino acid oxidase were found in high activity in the tissues of representative species of terrestrial gastropods. Analytical subcellular fractionation demonstrated that both of these oxidases co-localised with the peroxisome markers, acyl-CoA oxidase and catalase, in the digestive gland homogenate. Electron microscopy of peak peroxisome fractions showed particles of uniform size with generally well preserved variably electron-dense matrices bounded by an apparently single limiting membrane. Many of the particles exhibited a core region of enhanced electron density. Catalase cytochemistry of peak fractions confirmed the peroxisome identity of the organelles. Peroxisome-enriched subcellular fractions were used to investigate the properties of gastropod D-aspartate oxidase and D-amino acid oxidase activities. The substrate and inhibitor specificities of the two activities demonstrated that two distinct enzymes were present analogous to, but not identical to, the equivalent mammalian peroxisomal enzymes.     

Dibenzothiophene desulfurization in hydrocarbon environment by Staphylococcus sp. resting cells

Staphylococcus sp. strain S3/C desulfurized dibenzothiophene/n-hexadecane (3 mg ml^–1) in a hydrocarbon aqueous biphasic culture. The resting cells decreased the sulfur content of the hydrocarbon phase by 57% at 2.2 mg l^–1 h^–1 in the absence of any additional carbon and sulfur source.     

Cytological studies on triploid Trigonella corniculata L.

Two spontaneous triploid plants of Trigonella corniculata (3n=24) were observed in a population raised from irradiated seeds. Up to seven trivalents per cell were observed. One of the plants appeared to be a double translocation heterozygote involving two non-homologous chromosomes, and therefore could form a quadrivalent, a ring trivalent and bivalents without corresponding univalents.