Gamal M. Imam

Studies on the synthesis of valine moiety of 6-aminopenicillanic acid by preformed mats of Penicillium chrysogenum.

Summary1.The formation of valine from acetone and glycine and from propan-2-ol and glycine was demonstrated. The transformation of propan-2-ol to acetone was suggested.2.Acetone, propan-2-ol, glycine, valine and cysteine stimulated the biosynthesis of 6-APA when supplemented separately to the medium. These compounds are arranged in a descending order with respect to their stimulative influence.3.Coenzyme A influenced favourably the formation of 6-APA.4.A mixture of acetone, glycine, and cysteine was the most stimulative among the other combinations tried.5.A presumed sequence of reactions between acetone, glycine and cysteine, probably involving CoA, was thus suggested for the biosynthesis of 6-APA. The reactions involve dehydration and dehydrogenation with the liberation of two molecules of water and two hydrogen atoms.

In vitro liquefaction of human blood clots by metabolites of bacillus subtilis

SummaryThe influence exerted by some cultural conditions on the ability of metabolites of Bacillus subtilis to liquefy the human blood clots was studied. Crude enzyme preparations capable of liquefying the clots were isolated from the culture solutions. The aminoacids produced during the liquefaction process could be traced. Both of the enzyme preparation and the metabolism solution induced no obvious toxic effects when injected into veins of rabbits.

Biosynthesis of fat from some organic acids in submerged cultures of penicillium spinulosum

SummaryThe formation of fat from citric, succinic, fumaric and malic acids by Penicillium spinulosum has been investigated. Sodium arseite, β-sulfonic propionic acid and mono-iodoacetate was found to control unfavourably the formation of fat from the organic acids by the preformed pellets of the organism. Moreover, iodoacetate reduced the mean molecular weight of the component fatty acids. The β-sulfonic propionic acid though reduced the yields of fat yet the ratio fat/100 g of acid consumed was not markedly altered by this compound. A modified chromatographic method was described for the assay of different acids.

The determination of compounds by use of chromatography on thin-layer chromatostrips

A technique is described for the quantitative analysis of organic compounds by chromatography on narrow strips of glass plate bearing a thin layer of adsorbent. A relationship between the length, L, of the zone occupied by a compound, the weight, C, of compound applied and the distance, D, travelled by the developing solvent, viz., L= K log C log D(where K is a constant), has been found to hold under specified conditions and can be used to determine organic compounds alone or in admixture.