Science progress. 



Vol. VII. (Vol. II. of New Series). APRIL, 1898. No. 7. 



THE PHOSPHORUS-CONTAINING SUB- 

 STANCES OF THE CELL. 



OUR knowledge of the form and position in which the 

 phosphorus is held in the animal cell has of recent 

 years become considerably advanced by the researches of 

 Miescher, Kossel and their co-workers, and has been greatly 

 stimulated by the discovery of Altmann, that from the chief 

 and most abundant of the phosphorus proteids the phos- 

 phorus can be split off in the form of a complex acid 

 which he has called nucleic acid. The constitution of nucleic 

 acid has now been made the subject of a good deal of work 

 which has led to all the more promising results, because 

 though it is a very complex body, the size of its molecule is 

 small as compared with those of the highly complex proteids 

 by which it is accompanied. In this short paper we will 

 first orive an account of nucleic acid itself so far as it is at 

 present known and then discuss the compounds in which 

 form it is present in the cell. 



NUCLEIC ACID. 



Nucleic acid was first prepared and described by 

 Altmann. 1 He obtained it best from yeast by treating the 

 cells for about five minutes with a large volume of 3 per 

 cent. NaOH. The alkali was then nearly neutralised 

 with hydrochloric acid and an access of acetic acid added. 

 Most of the proteid was thus precipitated, whilst the 



1 Altmann : Arch, filr {Anat. u.) Phys., 1889, p. 524. 



10 



