Abstract
The year 2015 marks the 100th anniversary of a publication by William Twort, in which he first described lysis of bacterial cultures by a filterable, self-replicating agent. In 1917, Félix d’Herelle, coined the name “bacteriophage” for the proposed agent. Two Belgian teams of microbiologists were among the few to critically examine the nature of the bacteriophage at that time. Although their experimental results agreed, their interpretations did not. Richard Bruynoghe interpreted them as supportive of d’Herelle’s notion of an ultramicroscopic microorganism. Jules Bordet found the proposal of a complex organism unnecessary and saw the bacteriophage as a simple endogenous bacterial enzyme endowed with capacity to induce its own secretion as well as ability to cause lysis of the bacteria. Two decades would elapse before bacteriophages were visualized and confirmed to be organized particles. However, by that time, Bruynoghe’s work, that had only been published in short notes in society proceedings, was virtually forgotten. The present paper revives his original observations and arguments, while also recognizing that Bordet’s alternative hypothesis had scientific merit.