Organic Growth Factor Requirements of Tobacco Tissue Cultures

From the standpoint of physiological genetics the development and functioning of an organism consist essentially of an integrated system of chemical reactions controlled in some manner by genes. It is entirely tenable to suppose that these genes which are themselves a part of the system, control or regulate specific reactions in the system either by acting directly as enzymes or by determining the specificities of enzymes [1]. Since the components of such a system are likely to be interrelated in complex ways, and since the synthesis of the parts of individual genes are presumably dependent on the functioning of other genes, it would appear that there must exist orders of directness of gene control ranging from simple one-to-one relations to relations of great complexity. In investigating the roles of genes, the physiological geneticist usually attempts to determine the physiological and biochemical bases of already known hereditary traits. This approach, as made in the study of anthocyanin pigments in plants [2], the fermentation of sugars by yeasts [3] and a number of other instances [4], has established that many biochemical reactions are in fact controlled in specific ways by specific genes. Furthermore, investigations of this type tend to support the assumption that gene and enzyme specificities are of the same order [5]. There are, however, a number of limitations inherent in this approach. Perhaps the most serious of these is that the investigator must in general confine himself to a study of nonlethal heritable characters. Such characters are likely to involve more or less non-essential so-called "terminal" reactions [5]. The selection of these for genetic study was perhaps responsible for the now rapidly disappearing belief that genes are concerned only with the control of "superficial" characters. A second difficulty, not unrelated to the first, is that the standard approach to the problem implies the use of characters with visible manifestations. Many such characters involve morphological variations, and these are likely to be based on systems of biochemical reactions so complex as to make analysis exceedingly difficult.

https://www.pnas.org/content/pnas/27/11/499.full.pdf

Genetic Control of Biochemical Reactions in Neurospora

Isolates from different species-groups of Trichoderma were tested for production of non-volatile antibiotics, by an agar layer technique. Preliminary studies on the chemical nature of these antibiotics were made. Many isolates produced non-volatile antibiotics active against a range of fungi. The ability to produce such antibiotics varied between isolates of the same species-group as well as between isolates of different species groups. The susceptibility of fungi to these antibiotics varied widely; Fomes annosus (Fr.) Cooke was the most susceptible and Fusarium oxysporum Schlecht, ex Fr. the most resistant of the test fungi used. Gliotoxin and viridin were not produced, but other chloroform-soluble antibiotics, including trichodermin and peptide antibiotics were detected.

Antagonistic properties of species-groups of Trichoderma: II. Production of volatile antibiotics

Natural products to drugs: natural product derived compounds in clinical trials

The development of artificial media for marine algae.

https://www.pnas.org/content/pnas/37/9/570.full.pdf

Antibiotic Substances From Basidiomycetes VIII. Pleurotus Multilus (Fr.) Sacc. and Pleurotus Passeckerianus Pilat

1. A simple method of growing the isolated meristematic tissue of higher plants, excised root tips and stem tips, under sterile conditions is described. 2. The excised root tips of peas, corn, and cotton make considerable growth in the dark in solution cultures containing mineral salts and glucose or levulose. 3. The excised root tips of peas, corn, and cotton make little growth in the dark in solution cultures containing mineral salts and lacking carbohydrate. 4. The growth of the isolated root tips of peas, corn, and cotton is markedly greater in solution cultures containing glucose than in those containing levulose. 5. The excised roots of corn respond normally to gravity when grown on agar containing mineral salts and glucose. 6. The isolated shoot tips of peas and corn make considerable growth in the dark in sterile solution cultures containing mineral salts and glucose or levulose, but little in the absence of carbohydrates. 7. The excised shoot tips of corn and peas grown in sugar solutions remain ...

William J. Robbins

Papers

Antibiotic Substances From Basidiomycetes VIII. Pleurotus Multilus (Fr.) Sacc. and Pleurotus Passeckerianus Pilat

Cultivation of Excised Root Tips and Stem Tips Under Sterile Conditions

Gibberellic acid and the reversal of adult hedera to a juvenile state

Antibiotic substances from Basidiomycetes+. VII. Clitocybe illudens.

Growth factors for Trichophyton mentagrophytes.