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Studies on the properties of soaps are of importance because of their common use as detergents, in the preparation of vaccines, in the treatment of disease, and because of their natural occurrence in the animal body where they may have some effect in determining the resistance of the animal organism to infection. Reichenbach (1908) studied the action of soaps on Escherichia coli and found that potassium stearate, pahmitate, and myristate were effective in killing this organism, while the oleate, erucate, and linoleate were inactive. Walker (1924-1926) showed that sodium and potassium soaps of the same acid did not vary greatly in their germicidal action. The lower members of the series such as the butyrate, valerate, caprylate, and caproate, had little or no germicidal effect. He found the pneumococcus to be very susceptible to laurates, oleates linoleates, and linolenates. Streptococci were killed much like the pneumococci but at higher concentrations of the soap. Escherichia coli, Eberthella typhi, Shigella paradysenteriae, Salmonella paratyphi were killed by moderate concentrations (N/20 to N/40) of the saturated soaps (laurates to stearates) but were very resistant to the unsaturated soaps. Eggerth (1926-1931) studied the germicidal action of alpha substituted soaps. He found that the soaps of the alpha bromo fatty acids were usually more germicidal than the unsubstituted. The alpha hydroxy soaps exhibited a high germicidal activity 1 This paper covers, in part, work submitted to the Graduate School of the University of Minnesota by the author in partial fulfillment of the requirements for the degree of Doctor of Philosophy. The work was supported in part by a grant from the special emergency fund of the

Among the toxins produced by certain strains of staphylococci is one which is capable of causing food poisoning symptoms in man. Although a number of workers including Denyes (1), Owen (2), and Barber (3) had called attention to the etiological r61e of staphylococci in certain outbreaks of acute illness characterized by nausea, vomiting, and diarrhea, it was not until the work of Dack (4) and Jordan (5) and their coworkers that interest was stimulated in staphylococcus food poisoning. These later investigators demonstrated that the symptoms were due to a filterable toxin which was thermostable. This toxin was found to be quite distinct from the hemolytic, lethal, and dermo-necrotic toxins which are relatively thermolabile. Since its main effect seemed to be on the gastro-intestinal tract, it was termed enterotoxin.The clinical symptoms in man usually begin 2 to 4 hours after ingestion of the contaminated food, and include dizziness, nausea, vomiting, diarrhea, and weakness. Recovery is rapid, and the individual feels practically well 24 hours later. Fatalities are rare, and are probably caused by an actual tissue invasion by the staphylococcus rather than by the enterotoxin alone. In the fatal case reported by Blackman (6), the illness began with the above symptoms, but at necropsy a staphylococcal infection of the jejunum and ileum was found.The investigation of enterotoxin-producing organisms has been retarded by the fact that, until recently, the only known susceptible subjects were man and the monkey, and these exhibited considerable variation in the response to enterotoxin. In 1936, Dolman, Wilson, and Cockcroft (7) demonstrated that kittens injected intraperitoneally with formalinized or

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A considerable amount of work is being done on the histochemical localization of some enzymes in the tissues of higher animals and plants. However,although bacteria have been frequently studied for a few isolated substances such as glycogen, lipids, nucleic acids, and protein, no determined effort has been made to analyze these lower forms of life for their various enzyme systems by histochemical methods. The localization of enzymes and chemical constituents in bacteria offers possibilities of determining further details of their internal anatomy, and may help to shed light on the problem of the bacterial nucleus. In addition, such studies may aid in classifying microorganisms as well as in giving a better understanding of their physiology.