RANGE OF CHEMICAL ACTION BY BACTERIA 



others are found in the soil around oil-wells which oxidise 

 paraffin hydrocarbons to carbon dioxide and water. It is 

 probably not unscientific to suggest that somewhere or other 

 some organism exists which can, under suitable conditions, 

 oxidise any substance which is theoretically capable of 

 being oxidised. 



Here then we have a small sample of the fascinating field 

 of chemical activity presented by bacteria. There are many 

 questions which immediately occur to the chemist. How do 

 these micro-organisms carry out these reactions which cannot 

 be achieved in the laboratory ? Is it possible to utilise their 

 activities to carry out such and such a reaction 1 Can their 

 metabolic activities be exploited on a commercial scale ? 

 Why are some bacteria pathogenic to man ? Bacterial meta- 

 bolism has been studied ever since the initial investigations of 

 Pasteur, and as new techniques are devised our knowledge is 

 continually increasing and accumulating, but it is still true 

 to say that we understand only a very small part of the 

 activities of bacteria and there is immense scope for research 

 in this field. In this book an attempt will be made to answer 

 some of the queries that arise in the mind of the chemist, 

 and in many cases the answers will be such, that they will 

 merely indicate our need for further research. 



Chemical reactions carried out by living material take place 

 in simple steps and these steps can often be demonstrated 

 within the cell either by suitable treatment of the cell, or by 

 the addition of chemicals which will combine with intermediate 

 products or with enzymes involved in the formation of these 

 products, and so break up complete reactions into their 

 individual steps. The number of basic reactions is few and 

 include the following: 



1 . Reduction : the addition of hydrogen or, alternatively, the 

 removal of oxygen from the molecule attacked. 



2. Oxidation: the removal of hydrogen or, alternatively, the 

 addition of oxygen. 



3. Dehydration : the removal of HgO from the molecule. 



