May 3, 1918] 



SCIENCE 



429 



tide linking. It is evident, however, that 

 such tautomeric structures, enol-lactim 

 and keto-lactam, may be present in other 

 groupings, and the results of this investi- 

 gation in no way limit the lipolytic activ- 

 ity to the peptide linking. In view of the 

 complexitj' of the protein molecule, it is 

 highly probable that such tautomeric 

 groupings are present in combination with 

 other groups and that the specificities of 

 the actions are in part dependent upon 

 these. 



It must be admitted that the treatment 

 of proteins with alkali to form active sub- 

 stances is rather drastic. Unquestion- 

 ably, simpler methods, comparable to those 

 taking place in nature, will be found to pro- 

 duce the same effects. The fact that dilute 

 alkalis inactivated the castor bean globu- 

 lin lipase, while a certain higher concen- 

 tration of alkali produced an ester-hydro- 

 lyzing substance from the inactive globu- 

 lin preparation, indicates that differently 

 placed groups in the molecule were in- 

 volved in these two changes. 



In how far the conclusions reached with 

 lipase may be applied to other enzymes is 

 a question. It seems probable, because of 

 the comparatively simple treatments by 

 which most enzjTnes may be inactivated, 

 that with them also a' simple rearrangement 

 or perhaps tautomeric change is connected 

 with loss in activity. There is, however, 

 no reason to suppose that the active group- 

 ing is the same for all enzymes. Each 

 enzyme must be studied separately and 

 conclusions as to the chemical nature of 

 one active enzyme grouping can not with- 

 out further evidence be applied to an 

 enzj-me grouping connected with a different 

 action. The work described with lipase has 

 given a definite point of view, if nothing 

 further, from which the study of this 

 enzyme may be continued, and it seems 



probable that similar systematic studies 

 with other enzymes would yield interesting 

 and valuable results. 



K. George Falk 

 Hakriman Research Laboratoby, 

 Roosevelt Hospital, New York 



THE CONSERVATION OF WHEAT 



The U. S. Food Administrator has done, 

 and is doing, a splendid work in the conserva- 

 tion of wheat, notwithstanding the- many ob- 

 stacles which he has had to overcome. He 

 has met, with wonderful ability and success, 

 one of the most difficult situations of the ages. 

 At times he has been harassed by self-appointed 

 experts and advisers who have often hindered 

 when they should have heli)ed in the conser- 

 vation of food, particularly of wheat. This 

 is a time to put aside hobbies and pet theories 

 and look the facts squarely in the face. 



One of the suggestions frequently offered to 

 make the wheat crop go farther is to mill it 

 so as to include with the flouj a portion, or 

 all, of the wheat by-product, and then to re- 

 quire universal use of such a flour. The pres- 

 ent ruling of our Food Administrator, permit- 

 ting the manufacture of whole-wheat flour 

 and also of flour that contains approximately 

 75 per cent, of the wheat kernel, rests upon a 

 sound, economic basis. The usual argujuent 

 of the whole-wheat flour advocates is that the 

 product is more nutritious, and that the wheat 

 can be made to go farther when it is milled 

 so as to include a part or all of the by-product. 



The March 8 (1918) issue of Science con- 

 tains an article : " Shall We Eat Whole Wheat 

 Bread ? " by L. A. Dutcher, in which reference 

 is made to my work on the nutritive value of 

 breads. This article follows the usual trend 

 of the whole-wheat bread advocate. I would 

 make no mention of the article if it were not 

 for the fact that I believe attention should be 

 called to certain omissions, a misquotation and 

 a selective and unusual use of data from my 

 publications that might lead to erroneous con- 

 clusions, particularly as one of the bulletins 

 quoted, Minn. No. 54, is no longer in print, 

 or available for distribution. 



