Theodore E. Friedemann

The Starvation Ketosis of a Monkey.

In sharp contrast to human beings, most animals (dog, cat, pig, steer, goat, guinea pig, rat, rabbit, etc.) appear to develop only slight ketosis when starved. In man, on the other hand, starvation ketosis is a regular phenomenon, and is apparently a necessary consequence of the failure to metabolize a sufficient amount of carbohydrate. And conversely it is believed that the metabolism of carbohydrate is essential for the normal complete combustion of the precursors of the acetone bodies. This seems applicable only to man. The ability to avoid ketosis without the direct intervention of metabolizing glucose appears to be possessed by most animals. Man is the exception. That animals have high tolerance for the acetone bodies is indicated by the results of acetoacetic acid injection (dog 1 , mouse 2 , cat 3 ). This ability of animals to burn acetone bodies (apparently without the antiketogenic action of carbohydrate) would seem to be not an acquired property, but rather a function normal to all animals with the exception of man in whom it appears to have been lost. A parallel case is perhaps the ability to further metabolize uric acid to allantoin, possessed in general by mammalia, but lacked by man and the chimpanzee. The following observation has been made on a fasting monkey, which developed a ketosis quite comparable to that of man which was promptly abolished by glucose and food. Whether the results are representative of the behavior of the species or of primates generally can be determined only after observations on other individuals, though the writer sees no reason to suppose that the behavior of this monkey is exceptional.

Metabolism of Pathogenic Clostridia in Complex Carbohydrate-Rich Culture Media.∗

One of the characteristics of the pathogenic and many of the non-pathogenic clostridia is their marked ability to digest and further metabolize proteins and protein derivatives during growth in the usual culture media. 1 2 3 4 5 Ammonia, volatile acids, CO2, and H2 are produced during the anaerobic breakdown of proteins and amino acids. 1 2 3 4 5 6 7 Carbohydrates are the source of most of the energy in carbohydrate-rich media,† and large quantities may be consumed, due to the formation of neutral compounds, CO2 and H2. Dextrose yields ethyl alcohol and formic (CO2 and H2), acetic, butyric, and lactic acids. 2 8 9 10 11 In the later stages of the fermentation the commercially important clostridia may yield very large quantities of acetone, and iso-propyl and butyl alcohols. 3 9 12 The same products may be obtained from lactic and pyruvic acids. 13 14 15 Acetic acid may be converted into acetone and butyl alcohol. 12 The presence of acetone and the higher alcohols in cultures of pathogenic clostridia has not been reported. Acrolein is found in cultures of Cl. perfringens (welchii) in glycerol broth. 16 The presence of acrolein in fruit juices and the bitterness of wine have been attributed to the growth of this organism. 17 Acetone may be reduced to iso-propyl alcohol; 18 aldehydes and acids are reduced to alcohols; 2 15 18 19 20 and acetaldehyde may yield acetylmethyl carbinol. 20 The clostridia thus appear to be versatile in their abilities to carry out chemical reactions with a wide variety of substances. A comparative quantitative study of the metabolism of the pathogenic clostridia under identical conditions of growth has never been made, nor have the principal products of metabolism in the usual liquid media with added dextrose been determined. In the present paper, data from 5 species of pathogenic clostridia are presented.

Metabolism of Pathogenic Bacteria Growing Under Aerobic Conditions in Carbohydrate-rich Culture Media.∗

Summary and Conclusions Diplococcus pneumoniœ, Eberthella typhosa, and Escherichia coli were grown 24 hours at 37.5°C in meat infusion or meat extract culture medium enriched with 1% of peptone, 0.7 to 1.8% of Na2HPO4. 12 H2O, and 1% of glucose. The pneumococcus was grown under anaerobic as well as highly aerobic conditions. The principal products were lactic acid, formic acid, acetic acid, and ethyl alcohol. The last 3 products appeared in the approximate ratio of 2 to 1 to 1. The reactions representing their formation most likely are: Glucose → hexose diphosphate → 2 triosephosphate → glycerophosphate and phosphoglycerate. Glycerophosphate → C2H5OH + HCOOH. Phosphoglycerate → phosphopyruvate → CH3COOH + HCOOH. These are anaerobic mechanisms. Only a trace of CO2 was obtained from pneumococci. Rapidly growing bacteria may metabolize sugar almost entirely by anaerobic mechanisms when grown under relatively aerobic conditions. The same intermediary reactions are probably also utilized by microörganisms when growing in tissues in the course of an infection.

Carbohydrate Metabolism of Oidium lactis and Bacillus subtilis in Complex Carbohydrate-rich Culture Medium.∗:

Summary Oidium lactis and B. subtilis were inoculated into culture media prepared from 0.3% solution of meat extract or an infusion of beef muscle, to which were added 1% of Witte peptone, 1 to 1.8% of Na2HPO4 · 12 H2O and 0.9% of dextrose. Both microorganisms grew rapidly at 37.5° and both yielded about 70% of iactic acid on the basis of the sugar consumed. Approximately one-fifth of the C3-intermediates from the sugar was further metabolized into 2 moles of formic acid and 1 mole each of acetic acid and ethyl alcohol. Their metabolism in the same culture medium is compared with that of Eberthella typhosa, Shigella paradysenteriae, Lacto-bacillus helveticus (casei eP) and Corynebacterium diphtheriae.

Free Volatile Acidity of Blood and Tissues Following Ingestion of Ethyl Alcohol.

Summary 1. A procedure is described for the determination of the free volatile acids of tissues. 2. Normal tissues of the dog, with the exception of brain, contain only traces, from 0 to 0.25 mM or cc N, of free volatile acidity per kg. This constitutes from 1 to 3% of the total volatile acids which can be obtained by hydrolysis with 2 N H2SO4. About 10%, from 1.5 to 2.0 mM, of all of the volatile acids of the brain are present either as free acid or in some form which is readily hydrolized. 3. The metabolism of ethyl alcohol in the dog does not result in an increase of the free volatile acids of the blood and tissues.

A Method for the Determination of Ethyl Alcohol.

Ethyl alcohol is either present as such or it may be formed under certain conditions by many plant and animal cells. It is the chief product of carbohydrate metabolism of non-pathogenic as well as pathogenic yeast-like organisms. 1 Smaller quantities have been found in bacterial and mold cultures. It is found also in blood (0.001 to 0.004%) and tissues (0.0007 to 0.0026%) of animals. 2 The usual physical methods are not applicable to the small amounts found in biological materials, and for this reason chemical methods have been proposed and used with a fair degree of success. The methods of Nicloux 3 and Widmark 4 depend upon oxidation of the alcohol by K2Cr2O7 in the presence of strong H2SO4. Varying degrees of oxidation are obtained, depending upon the condition. In the method which we propose the oxidation is carried out in 2 steps by KMnO4. It is first oxidized by hot alkaline permanganate (almost quantitatively) to oxalic acid. The latter is then completely oxidized on acidification with H2SO4. The low final acidity permits a more accurate iodometric determination of residual oxidizing agent. The sample, previously deproteinized, is pipetted into a 300 cc. Kjeldahl flask. Talcum is added, and the volume is made up to about 150 cc. Eighty to 100 cc. are distilled into another 300 cc. Kjeldahl flask containing about 50 cc. of cold water. An apparatus similar to, but somewhat larger than that recently described by Bok, 5 is satisfactory.

Metabolism of the Tubercle Bacillus in Long's Synthetic Medium.

Conclusions It is shown (1) that the rapid growth of the microorganisms is directly related to the consumption of glycerol and other constituents of the synthetic medium, and (2) that rapid autolysis occurs after exhaustion of the nutrients.

The Direct Determination of Ethyl Alcohol in Saliva without Distillation.

Summary All but a small, but relatively constant, quantity of the oxidizable material of normal saliva may be removed by the addition of 2 reagents: (1) a solution of CuSO4, HgSO4, and ferric sulfate, and (2) a suspension of Ca (OH)2. The residual material from normal saliva is equivalent to 10.5 ± 4.6 mg. 70 of ethyl alcohol. A procedure for the direct determination, without distillation, of ethyl alcohol in saliva is described. The results are 11.2 ± 3.3 mg. % higher than by the method of Friedemann and Klaas.

The Metabolism of Pathogenic Yeasts.

Conclusion The principal products of 13 pathogenic yeasts (12 monilia and Cryptococcus Iiominis) in a buffered peptonemeat-extract medium, with 5% glucose, were ethyl alcohol and CO2. The yield of metabolic products was identical with that from 3 non-pathogenic yeasts.