Dutch Microbiologist and Educator 1897-1985

Cornelis Bernardus van Niel was a Dutch microbiologist whose experiments with bacteria helped explain how photosynthesis occurs in plants. Sulfur bacteria particularly interested van Niel, because there was a controversy in the early 1900s concerning the bacteria. Scientists were not sure if the bacteria got their energy from chemicals in their environment or from sunlight. They knew that the bacteria used sulfur compounds and did take in carbon dioxide to create more complex carbon compounds, and van Niel wanted to determine which energy source the bacteria used to do this.

One problem was that previous scientists had usually studied cultures of bacteria that contained several different species. They knew that the bacteria needed light and also needed and stored sulfur compounds, but the interactions between different species in the cultures made experimentation difficult. Van Niel decided he...