Intimate genetic relationships and fungicide resistance in multiple strains of Aspergillus fumigatus isolated from a plant bulb

Fungal infections are increasingly dangerous because of environmentally dispersed resistance to antifungal drugs. Azoles are commonly used antifungal drugs, but they are also used as fungicides in agriculture, which may enable enrichment of azole-resistant strains of the human pathogen Aspergillus fumigatus in the environment. Understanding of environmental dissemination and enrichment of genetic variation associated with azole resistance in A. fumigatus is required to suppress resistant strains. Here, we focused on eight strains of azole-resistant A. fumigatus isolated from a single tulip bulb for sale in Japan. This set includes strains with TR₃₄/L98H/T289A/I364V/G448S and TR₄₆/Y121F/T289A/S363P/I364V/G448S mutations in the cyp51A gene, which showed higher tolerance to several azoles than strains harbouring TR₄₆/Y121F/T289A mutation. The strains were typed by microsatellite typing, single nucleotide polymorphism profiles, and mitochondrial and nuclear genome analyses. The strains grouped differently using each typing method, suggesting historical genetic recombination among the strains. Our data also revealed that some strains isolated from the tulip bulb showed tolerance to other classes of fungicides, such as QoI and carbendazim, followed by related amino acid alterations in the target proteins. Considering spatial–temporal factors, plant bulbs are an excellent environmental niche for fungal strains to encounter partners, and to obtain and spread resistance-associated mutations.     

Increased uptake of thymidine in the activation of sea urchin eggs. II. Cooperativity with phosphorylation, involvement of the cortex, and partial localization of the kinases

Uptake and phosphorylation of exogenously supplied thymidine are stimulated in Strongylocentrotus purpuratus eggs after fertilization. Before fertilization, the rate of uptake is low and less than 10% of the thymidine entering the egg is phosphorylated. After fertilization, the rate of uptake increases over 50-fold and greater than 90% of the thymidine is immediately phosphorylated. These results imply that there is close cooperativity between fertilization-induced uptake and phosphorylation of thymidine. To gain insight into the structural basis of this apparent cooperativity and to provide a partial localization of the kinases, uptake and phosphorylation were measured in centrifuged eggs, and in centrifuged nucleate and anucleate merogons. Electron micrographs show that in these cells, the inner cytoplasmic contents are stratified according to density and displaced within the egg, whereas the outer cortical region of the cytoplasm remains intact. Uptake and phosphorylation of thymidine are fully stimulated in these eggs and merogons after fertilization, suggesting that both processes are mediated by an intact egg cortex. In support of this suggestion, we report that controlled disruption of the egg cortex prior to fertilization by treatment with cytochalasin B (CB) significantly reduces the rates of uptake and phosphorylation after fertilization. The full stimulation of phosphorylation in nucleate and anucleate merogons eliminates any localization of the catalyzing enzymes (thymidine kinase and thymidylate kinase) in the maternal nucleus and other inner cytoplasmic contents differentially segregated by centrifugation.     

Biosynthesis of cannabinoid acids

Malonic acid, mevalonic acid, geraniol and nerol were incorporated into tetrahydrocannabinolic acid and cannabichromenic acid in Cannabis sativa. The pathway from cannabigerolic acid to tetrahydrocannabinolic acid via cannabidiolic acid was established by feeding labelled cannabinoid acids. Cannabichromenic acid was shown to be formed on a side pathway from cannabigerolic acid.     

Application of Y chromosomal repetitive sequences to sexing mouse embryos

Identification of sex is often necessary to evaluate genetic or teratogenetic effects on embryonic development. A simple molecular technique to identify the sex of mouse embryos was studied using a Y chromosomal repetitive sequence (designated 145SC5). Since this technique does not require purification of DNA, it is particularly suitable for processing many embryos. Furthermore, 145SC5 detects 1% contamination of male DNA in a male-female DNA mixture. These results suggest that 145SC5 is a powerful molecular tool in a variety of studies on mouse development.     

Ultrastructural study of the relations between Leptomonas oncopelti (Noguchi and Tilden), protozoa trypanosomatidae,and the rectal wall of adults of Oncopeltus fasciatus dallas,hemiptera lygaeidae

A laboratory colony of Oncopeltus fasciatus was found to be infected by Leptomonas oncopelti. The flagellates form a carpet attached to the cuticular intima of the rectal glands of adult bugs. The epithelial cells of these glands are characterized by infolded apical plasma membranes associated with mitochondria; the overlying cuticular intima shows endocuticular canals. The Leptomonas are attached by hemidesmosomes, located most often at the tip of the flagella. The Protozoa multiply by budding and the resultant straphangers cling to the parental flagellum. Adhesion of the flagellates to the cuticular lining is so strong that detaching flagellates carry with them the outer part of the epicuticle. Epicuticle repair presumably occurs through the endocuticular canals.