Taxonomy of Bacillus

Abstract

A century ago, when a young scientist detected that a bacterium which Pasteur had thought to be a coccus was in fact a short rod, Pasteur’s comment was, “I wish I could convey to you how little that information excites me” (Duclaux, 1896). Obviously, Pasteur was interested in microorganisms mainly for what they do rather than what they are. Whereas this remains a legitimate interest today, early bacteriologists felt that, with the increasing diversity of organisms isolated, there was a need to arrange bacteria distinctly. The easiest way to do this was to put them into groups with common properties, to study the relationships of such groups and their role in nature, and to develop methods that would enable scientists to identify new isolates with already known groups.