424 



Histon and its Preparation 



[April 



washing with alcohol and ether, and drying to constant weight. 

 Ackerman used the ammonia-precipitated product for his analyses. 



K. Centrophorus histon: Kossel and Kutscher, 1906-7 

 (15). Report was given of the preparation but no details as to 

 method or properties. 



L. Reviews. The available reviews merely summarize the 

 methods of preparation already in the literature. Oppenheimer 

 (1909) recommends a method of preparing histon which is essen- 

 tially that of Lihenfeld (19).^ Abderhalden (1909-10) recom- 

 mends the method of Kossel and Kutscher (16).^ In our experi- 

 ence both of these methods result invariably in a product that is 

 practically insoluble in water. The only other method reported in 



TABLE I 



Data pertaining to percentage elementary composition of histons 



Kind 



1. Goose-blood (12) 



2. Goose-blood (12) 



3. Thymus (19, 2) 



4. Salmin-albumose (22) 



5. Globin (23. 2)^ 



6. Arbacin (21) 



7. Scombron (2) 



8. Para-histon (9) 



9. Gadus (16) 



10. Lota (8) 



11. Hen-blood (i) 



12. Centrophorus and 



Spharechinus (15) 



Precipitated by 



NaCl 

 NH4OH 

 NH4OH 

 NaCl or 



(NH4)2S04 



NH40H 



Alcohol 

 NH4OH 

 Alcohol 

 NH4OH 



NH4OH 



NH4OH 



C 



50.88 

 50.90 

 52.31 

 52.14 

 52.34 

 52.31 



51.21 

 59-47 



49.86 

 51-91 



H 



7-05 

 7.16 

 7.06 

 7.20 



7-31 



7.60 

 7.20 



7-23 

 7-31 



O 



23-44 



20.32 



N 



17.77 



8.46 

 7-42 

 8.35' 



7.64 

 6.80 

 6.89 

 5-91 

 9-79 

 7-97 

 8.65 

 8.64 

 6.46 

 6.49 

 8.31 



No data given by Kossel. 



0.42 

 0.79 



0.00 



Ash 



0.52 

 0.6s 

 0.66 



0.52 

 0.84 



^ Extracted minced, fat-f reed, glands with water and precipitated with acetic 

 acid. Histon was extracted with 0.8 per cent. hydrochloric acid Solution and 

 the histon precipitated with ammonia. 



*The fat-f ree glands were extracted with water and sufficient hydrochloric 

 acid was added to make the strength of the acid 0.8 per cent. The filtered 

 extract contained the histon, which was precipitated with ammonia. 



* Second figure for N is that of Bang and Fleroff. 



* All determinations by Bang except second N. 



