Receive (d Julyl 15, 1966. Summnary. Poly-L-lysine, poly-a, y-diaminol)utyric aci(l aiu(l basic proteins cause efflux of betacyanin from beet root tissues to varying degrees. MAembrane activities fall in the order: polylysine > poly-a,y-diaminobutyric acid > polyarginine (protamine), suggesting the importance of steric factors in side-chain to backbone relations.It was also observed that homopolymer activity > heteropolymer activity, using ribonuclease and lysozyme as examples of the latter. Among polylysines, there appears to be an optimal chain length at a molecular weight eqtual to 50,000. Lowered activity of larger polymers is interpreted in terms of a diffusion barrier, the cell wall.Polylysine and Ca++ exhibit competitive kinetics, and Ca++ otherwise is far more active than other cations. It is assumed that polylysine displaces Ca++ from anionic centers on the membrane, but cannot confer equivalent dimensional stability, rendering the membrane leaky. The possible role of cationic shielding in ionic stabilization of the membrane was also considered.
In attempting to prepare the maleic anhydride adduct of sorbic acid by simple fusion of the reactants as originally described by Diels and Alder (1), difficulty was experienced in obtaining the desired compound, I. The reaction was therefore investigated further in order to determine suitable conditions for the preparation and the cause for the failure of the first attempts.
A living, ammonia-obligate, umbellate form, similar to the Precambrian microfossil Kakabekia umbellata Barghoorn, has been isolated from two soil specimens collected at Harlech, Wales. This organism is amenable to culture on agar and in broth. The two soil specimens are similar in that they differ from a typical clay loam in high content of carbon, hydrogen, and organic nitrogen and low levels of sodium, potassium, and titanium. In all other constituents, such as calcium, magnesium, and iron, they are quite dissimilar. Kakabekia-like forms can be grown in glucose-anmonia media with the latter as the sole source of nitrogen, but they can also be grown on peptone and silicate in glucose-free media. Ammonia is necessary, and growth is always slow without glucose. The fission process was not observed, but the enlargement and differentiation of a preumbellate structure into its "mature" form, followed by disintegration (senescence) of this stage, was seem. An ontogeny is proposed in which the stalk and basal bulb of the complete umbellate structure are assumed to be part of the reproductive appartus.
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