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En enzyme system has been found in peas which converts mevalonic acid to isoprenoid compounds. Among the intermediates in such conversion are mevalonic acid-5-phosphate and pyrophosphate, isopentenyl pyrophosphate and dimethylallylpyrophosphate. Among the products formed by the system are the pyrophosphates of geraniol, farnesol, nerolidol and higher isoprenoid alcohols.

The sequence in which a variety of enzymes and metabolites are affected by gibberellic acid after application of the hormone to aleurone layers of half seeds of barley (Hordeum vulgare var. Betzes) and half seeds of wheat (Triticum aestivum var. Gensee) was investigated. With barley aleurone layers the first hormonal effect observed was the increased secretion of soluble carbohydrate, some of which appears to be a glucan containing some beta-1,3 linkages. This was followed by increased oxygen consumption and increased secretion of ATPase, GTPase, phytase, phosphomonoesterase, phosphodiesterase, inorganic phosphate, carbohydrates other than amylase, peroxidase and amylase. Similar sequential effects were seen in wheat half seeds. Increased activity of alcohol dehydrogenase in barley seeds was elicited by the hormone but there was no effect on glucose-6-phosphate isomerase.

RNA prepared from fractions of chloroplasts and mitochondria sedimented at rates characteristic of ribosomal RNA. A predominance of the 18S species was frequently observed in preparations from chloroplasts from romaine lettuce and endive. The usual distribution, a preponderance of the 28S species, was observed in studies on tomato and spinach chloroplasts and mitochondria from mushroom and cauliflower. Comparisons of the base composition of RNA from organelles with their cytoplasmic ribosomal counterparts revealed that the 18S component from romaine lettuce chloroplast was different. A marginally significant difference was observed in the 28S particle from mushroom mitochondria preparations whereas distinct differences, reflected in all the bases, were seen when the 18S component of cauliflower mitochondria preparations was compared with cytoplasmic RNA.

A method for the identification of the 5'-linked termini of ribosomal RNA is described. The method involves the phosphorylation of the nucleosides released from the 5'-linked termini after hydrolysis of the ribonucleic acid chain with alkali. The radioactive 5'-nucleotide derivatives are formed by a nucleoside phosphotransferase mediated phosphoryl transfer from ((32)P) p-nitrophenyl phosphate to the nucleosides. The sensitivity of the method allows the use of small amounts of ribosomal RNA.Phosphorylation of the terminal nucleosides released from unfractionated cauliflower ribosomal RNA yielded radioactive adenylic acid and uridylic acid primarily, with the amount of adenylic acid being approximately twice that of uridylic acid.