Biochemical identification of thymosin alpha-1: its phylogenetic distribution and evolutionary implications.

1. Thymosin alpha-1, like reactivity, was found in several different species (insects, crab, protozoan, fungus and bacteria) by radioimmunoassay and immune fluorescence and as an extracellular product from the bacterial genus Mycobacterium. 2. Biochemically, thymosin alpha-1 has been isolated from combined crab visceral and nervous tissue by reverse phase HPLC. 3. The identification of thymosin alpha-1 in lower life forms suggests a more generalized exocrine origin in unicellular organisms prior to the development of the immune system or exocrine differentiation.

Toxicity of rhizonin A, isolated from Rhizopus microsporus, in laboratory animals.

Maize culture material of 25 isolates of the genera Rhizopus and Mucor caused deaths in day-old unsexed Pekin ducklings when fed as a 50% (w/w) mixture with duckling feed. Nine of these isolates were tested for toxicity in young inbred male BD IX rats, which were fed a mixture of 50% (w/w) culture material and rat feed. Only one isolate of Rhizopus microsporus was clearly toxic, causing 100% mortality in rats within 10 days. Growth in rats was reduced by adding culture material of this isolate to the feed in concentrations of 2.5, 5, 10 or 20% (w/w). The same isolate of R. microsporus was used to produce the mycotoxin rhizonin A. Pure rhizonin A was dissolved in dimethylsulphoxide and given to young male partially inbred albino rats by gavage in single doses of 70, 96, 131 or 180 mg/kg. The lowest dose exceeded the LD100. Evaluated by light microscopy, lesions in livers and kidneys were similar in rats fed culture material and in those intubated with rhizonin A. Hepatocytes showed changes ranging from degeneration to necrosis, the liver-tissue architecture was changed by disassociation of liver cell cords and there was periportal bile-duct proliferation. Renal tubular epithelium showed changes ranging from degeneration to necrosis.

Changes in esters of fatty acids of Rhizopus arrhizus during germination and growth.

Natural esters of fatty acids of Rhizopus arrhizus Fischer increased during the first 48 hr of growth. During the 48- to 72-hr period, there was a shift in concentration from the methyl esters to the ethyl esters of fatty acids.

Lipids of Rhizopus arrhizus Fischer.

The lipids of Rhizopus arrhizus Fischer mycelia and sporangiospores were extracted, isolated, and separated by thin-layer, liquid, and gas chromatography. Structural confirmations of the compounds were made by a gas chromatographmass spectrometer combination. The n-heptane fraction contained squalene (1%) as a major hydrocarbon constituent. Other major lipid classes detected were free fatty acids, naturally occurring methyl esters of fatty acids, triglycerides, sterols, and polar lipids. The polar lipids (44.4%) were found in the highest concentrations, and the triglycerides (22.1%), sterols (16.7%), and free fatty acids (11.7%) were present in lesser concentrations. This is the first report of naturally occuring methyl esters of long-chain fatty acids being present in fungal mycelium. There appears to be a preference for incorporation of unsaturated acids into the complex lipids, with the exception of the triglycerides. The major saturated fatty acids in the mycelium were palmitic (C(16)) and arachidic (C(20)), whereas the major unsaturated acids were oleic (C(18:1)) and linoleic (C(18:2)), respectively.

Protein synthesis during fungal spore germination. IV. Transfer ribonucleic acid from germinated and ungerminated spores.

Transfer ribonucleic acid (tRNA) fractions isolated from germinated and ungerminated spores of Botryodiplodia theobromae and Rhizopus stolonifer had acceptor activity for all 20 amino acids commonly found in protein, when tested with an enzyme fraction from germinated spores. Accordingly, it is unlikely that the absence of tRNA for a particular amino acid limits protein synthesis in fungal spores.

Choline and inositol distribution in algae and fungi.

Inositol and choline were present in varying amounts among the species of Rhodophyta, Phaeophyta, Chlorophyta, and Euglenophyta examined. However, in the two members of the order Fucales (division Phaeophyta) examined, no detectable amounts of choline were found. In contrast, the species of Cyanophyta examined contained no detectable amounts of either choline or inositol. All species of the fungal classes Phycomyceteae, Ascomyceteae, and Basidiomyceteae collected contained both inositol and choline in varying amounts. The red, brown, and blue-green algae usually contained much less inositol and choline than do plant and animals sources, but the fungi and the algae Chlorella and Euglena contained amounts comparable to those present in plant sources.