Upon the intracellular constituents of the typhoid bacillus / by Allan Macfadyen and Sydney Rowland.

  • Macfayden, Allan, 1860-1907.
Date:
1903
Catalogue details

Licence: In copyright

Credit: Upon the intracellular constituents of the typhoid bacillus / by Allan Macfadyen and Sydney Rowland. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    regards the typhoid organism, had been demonstrated, acute and definite toxic effects had proved remarkable by their absence. These various observations led us to endeavour to improve the methods employed, and to relinquish the procedure on lines analogous to those of Buchner, Hahn and other investigators in the study of expressed cell juices. The results, on the injection of such expressed cell juices into animals, were purely of an antibacterial character, an active toxin in the cell plasma and consequently antitoxic properties in the blood of the treated animals had not been demonstrated. This constituted a serious gap in the experiments, if we assume that an intoxication of the system in the case of enteric fever is a grave and perhaps the cardinal factor to be considered in the treatment of the disease. The filtering action of the Kieselguhr used in the filter pressing ap- peared to be the most likely reason for lack of success in this direction. The disintegration of the organisms was therefore attempted without the admixture of any foreign material which would render a subsequent filtration through Kieselguhr necessary. III. Experiments with cold grinding methods. The mechanical method of disintegration that appeared to be most likely to lead to successful results in the case of bacteria was their tri- turation whilst in a frozen and brittle condition. It had already been demonstrated (2) that an exposure to the temperature of liquid air (about —190® C) did not injure or destroy the vitality of bacteria, and that micro- organisms might be kept for as long a period as six months at this low temperature without any deleterious effect. This important point being determined, it appeared probable that the brittleness of the cells at this low temperature would favour their mechanical disintegration without any admixture of sand or other foreign substance. The most convenient agent for the production of the necessary cold was liquid air. Liquid air possessed two practical advantages: —it could be more conveniently handled than other substances that might possibly have given the necessary conditions of cold at higher temperatures than — 190 ® C and it furnished a fluid freezing bath in which the material to be ground could be directly immersed. These properties have proved of great practical value in the course of the experiments. A further ad- vantage was that at such a temperature the ordinary chemical processes would cease, changes due to heat would be eliminated, and the process if successful would furnish a quantitative yield of unaltered cell plasma. The experiments were successful and the feasibility of disintegrating micro-organisms per se, without any admixture of triturating substances was demonstrated. The complete disintegration of the typhoid bacillus was accomplished at the temperature of liquid air in a period of about two hours without the addition of sand or other foreign substance. The method has likewise been successfully applied to a number of bacteria, to other types of vegetable cells, and to animal organs and tissues, and their intracellular juices obtained for experimental purposes. The method entirely obviates the use of any accessory grinding or filtering substances and fulfils the conditions we desired to obtain for the study of intracellular constituents. These conditions were as follows: 1) That no chemical or heat changes should take place during the process of disintegration.