Confirmation by Chemical Synthesis of the Structure of 4-Ipomeanol,a Lung-toxic Metabolite of the Sweet Potato, <Emphasis Type="Italic">Ipomoea batatas</Emphasis>

WE have described the lung and liver toxicity of mould-damaged sweet potatoes and characterized briefly some abnormal metabolites responsible for these phenomena^1–4. The respiratory tract toxin, 4-ipomeanol (1-[3-furyl]-4-hydroxy-1-pentanone) (VI), may be responsible for the typical lung oedema of cattle that are fed mouldy sweet potatoes as well as a similar pathological state in mice fed or injected with the pure compound.     

A METHOD FOR THE FRACTIONATION AND PURIFICATION OF SEA URCHIN SPERM

Procedures for fractionation and purification of sea urchin sperm subunits were studied. Fragmentation of cells was observed rather than fractionation of cell subunits when classic sonication or homogenization techniques were used. Calcium shock in alcohol solution which successfully removes Protozoa cilia was not effective in removing sperm flagella. Alcohol was found to induce cohesion among whole sperm rendering separation of isolated subunits by centrifugation impossible. Calcium shock without alcohol in the medium was not effective in achieving dissociation of sperm subunits.
Successful fractionation of sperm subunits was achieved by application of a stepwise vortex-shearing action in a 0.22 micron filtered calcium-free medium. Analysis by Nomarski optics indicated little or no cellular fragmentation. Centrifugation with various discontinuous sucrose-sea water solutions proved to be a successful technique to purify the fractionated heads, midpieces, and tails.
The procedures reported here can be used to obtain fractionated and purified sperm cell heads, midpieces, and tails. These procedures do not require enzyme, homogenization, or sonication treatment of the material.     

The minute books of the Linnean Club, from 1811 to 1955

Sometime during the early spring of 1970 I was asked to write an account of our old minute books and was given a large box containing many books and sundry papers. All the old books were there and in good condition, except the first–1811 to 1815. So I wrote a report lamenting the absence of this book, but afterwards it turned up. It had never been lost, but being rather different from all the others it was not recognized. I now think this was rather fortunate, for the first book which is the most interesting, deserves ampler treatment. My report is kept strictly on the books, and only very occasionally have I drawn on information from the Society's records, or from the introduction to the list of the Club compiled by H. W. Monckton in 1922, using the Society's records.     

Nonadaptive Growth Responses of Tetrahymena pyriformis Grown on Single Bacterial Species*

SYNOPSIS. Turbidity changes caused by ingestion of bacterial cell suspensions by Tetrahymena pyriformis W were used to measure feeding capabilities. Tetrahymena was grown on washed killed cells of Aerobacter aerogenes, Azotobacter agile, Arthrobacter sp., Bacillus megaterium, Mycobacterium lacticola, Pseudomonas fragi, Sarcinia lutea, Serratia marcescens, and Thiobacillus thioparus for 6 months with serial transfers. After this time the rate of feeding on each bacterium gave no indication of an adaptation to the food bacterium.     

The Oxidation of Malate by Isolated Turnip (Brassica napus L.) Mitochondria: I. ULTRASTRUCTURAL OBSERVATIONS AND THE PRODUCTS OF MALATE OXIDATION

Washed and purified turnip mitochondria oxidize malate withrespiratory control and ADP: O values approaching 3.0 and producepyruvate as the principal product. Oxaloacetate is also producedin significant amounts but is removed by an endogenous mechanism.Malate dehydrogenase appears to be important to the oxidationof malate but requires the removal of oxaloacetate. During malateoxidation the mitochondria undergo configurational changes similarto those observed in animal mitochondria. Both ‘rightside-out’ and ‘inside-out’ submitochondrialparticles have been prepared. Right side-out particles oxidizemalate in the same way as intact mitochondria, whereas the inside-outparticles have a biphasic oxidation, the first phase producingoxaloacetate and the second, NAD-requiring phase producing pyruvate.It is concluded that malate oxidation is a complex process usingseveral enzymes located in the matrix compartment with a minorcomponent possibly on the outer face of the inner membrane.     

The ecology of the larger fungi; an investigation into the influence of rainfall and temperature on the seasonal production of fungi in a beechwood and a pinewood

The present paper deals in a somewhat generalized way with the influence of environmental factors, particularly rainfall and temperature, on the seasonal production of fungus sporophores in a beechwood and pinewood, both situated near Newbury (Berks.), during a selected part of the seasons 1933-6, and is intended to be complementary to the previous papers in the same series.