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Biomedical subjects

R A Nolan

Publications and source records attributed to R A Nolan.

16 recordsLinked to original sources
PubMed1981

Lipid level and total fatty acid composition for selected developmental stages of Entomophthora egressa.

The major fatty acids (greater than 10%) of Entomophthora egressa were C16:0 and C18:1 . Minor fatty acids, which varied with the stage of fungal development, included C11:0, C12:0, C13:0, C14:0, C15:0, C16;1, C17:0, C18:0, C18:2, C18:3 C:201, C20:2, C20:3, C20:4, C20:5 and two unidentified unsaturated fatty acids. Differences were observed between the total fatty acid levels of C12:0, C14:0, C17:0, C18:0, and C20:5 and the degree of unsaturation of the fatty acids of 37-h protoplasts grown in modified Grace's medium and a simplified growth medium (SGM). The levels of C12:0, C14:0, C18:1, C20:4, and C20:5 decreased and the levels of C18:0 and C20:2 increased with the formation of spherical hyphal body (shb)initials. With the production of mature shb increased levels of C12:0, C14:0, C15:0, C18:1, C20:4, and C20:5 were detected. During the germination of the shb the levels of C14:0, C16:1, C18;1, and C20:4 increased, whereas C15:0 and C20:5 levels declined. The fatty acid levels, except for C12:0, C13:0, and C20:2, remained constant during the mycelial stage. The degree of fatty acid unsaturation decreased during early stages of development (protoplasts through shb initials). In SGM the degree of fatty acid unsaturation was lowest during the shb initial stage and highest during the shb stage. The total lipid level increased during shb maturation and declined during shb germination.

Entomophthora↗
PubMed1979

Tabanomyces milkoi (Dudka and Koval) emended, genus novum, a fungal pathogen of horseflies.

A fungus originally described as a new species of Coelomomyces (C. milkoi) from larval Tabanidae in the Ukraine, USSR, is transferred to a new genus, Tabanomyces, and described in detail. The zygospores germinate to form a linear four-celled conidiophore, each cell producing a spherical conidium ejected as in Conidiobolus, thus confirming that the organism belongs in the Entomophthorales. The resemblance between the conidiophore of Tabanomyces milkoi and the basidium of the rusts supports the old concept that the rust fungi may be related to the Entomophthorales.

Journal Article↗
PubMed1977

Ultrastructural localization of succinate dehydrogenase in a self-parasitic isolate of Saprolegnia megasperma.

The enzyme succinate dehydrogenase (SDH, succinate: (acceptor) oxidoreductase, EC 1.3.99.1) was localized by the combined techniques of cytochemistry and electrom microscopy in the hyphae of a self-parasitizing isolate of Saprolegnia megasperma Coker. The enzyme was localized in the mitochondrial membranes; its activity was inhibited by malonate. Electron-dense deposits, whose formation was not prevented by the addition of malonate, appeared outsided of the hyphal cell walls. No evidence was found at the ultrastructural level within the vegetative hyphae for any abnormalities which could be linked to the phenomeonon of self-parasitism.

Fungi↗
PubMed1974

Cellulase localization in hyphae of Achlya ambisexualis.

Cellulase (EC 3.2.1.4; beta-1, 4-glucan glucanohydrolase) was localized at the ultrastructural level and found to occur in dictyosomes and vesicles, around the periphery of unidentified storage bodies, between the plasmalemma and the cell wall, and on the outer surface of the cell wall in the male strain (E87) of Achlya ambisexualis after treatment with the sex hormone antheridiol.

Cell Wall↗
PubMed1969

Phenoxyethanol: protein preservative for taxonomists.

Pieces of chicken heart or skeletal muscle were placed in a dilute solution of the antimicrobial agent 2-phenoxyethanol and stored at room temperature. Under these conditions, the serum albumin, lactate dehydrogenase, and malate dehydrogenase in these tissues survived in easily detectable amounts for at least 2 weeks. The surviving proteins appeared to be identical with those of fresh tissues in physical, catalytic, and immunological properties. Phenoxyethanol also preserved heart and muscle proteins of representatives of other vertebrate classes. Tissue samples collected in the analysis by biochemical taxonomists.

Animals↗
PubMed1966

D(-)-lactate dehydrogenase in lower fungi.

A lactate dehydrogenase, specific for nicotinamide-adenine dinucleotide and D(-)-lactate, has been detected in extracts from two fungi of the order Leptomitales (Oomycetes). Several fungi of this order carry out a lactic acid fermentation under conditions of reduced oxygen tension.

Chemical Phenomena↗