GREEN FLUORESCENT BACTERIA FROM WATER 89 



Gessard (1890) believed that two pigments were formed, a 

 fluorescent green and pyocyanin. 



Sullivan (1905) finds that pyocyanin formation is independent 

 of the presence of phosphate or sulfate. He did find, however, 

 that phosphorus and sulfur were essential. He recognizes a 

 fluorescent pigment arid pyocyanin and states that the same 

 variety of B. pyocyaneus may be made to display either of these 

 functions or both. Sullivan believes that ''the production of 

 pigment is not an essential vital act. As it is of no discoverable 

 advantage to the organism possessing the power of producing it, 

 its production is purely accidental." 



In a study of this pigment by the writer, a 4 liter flask of plain 

 broth was inoculated with strain 37 and left for eight weeks at a 

 temperature of about 25 °C. At the end of that time the medium 

 had assumed a dirty green color with a heavy precipitate in the 

 bottom of the flask. When the flask of broth was tested for 

 growth, a large number of living bacteria were found. This 

 culture was filtered through paper into a large bottle from which 

 different portions were taken for study. 



About 1^ liters were precipitated with lead acetate and allowed 

 to stand over night. In the morning this material was filtered 

 and divided into three portions. Each of these was extracted 

 with ether, chloroform and ligroin. The chloroform was the 

 only solvent which removed any of the pigment. It removed a 

 blue pigment which was increased in amount by subsequent 

 shakings in a separatory funnel. In four or five days this blue 

 chloroform solution changed to a red when left in bright light. 

 No rigagents seemed able to change it back to the green color. 

 In the dark the blue chloroform solution changed from a deep 

 blue color to a dark green which was permanent. 



Some of the chloroform solution was allowed to evaporate in 

 a crystallizing dish. A black residue which possessed crystalline 

 structure was left and this had a very strong odor similar to 

 some of the aromatic ammonium bases. This substance was 

 soluble in alcohol and water, insoluble in ether and red in acid 

 solution. Neutralization restored the green color again. 



The work here reported agrees with that reported by the 



