Non-Oxidative Enzymes of Spore Extracts 



Hillel S. Levinson 



Pioneering Research Division, Quartermaster Research and 

 Engineering Center, Natick, Massachusetts. 



MANY of the non-oxidative enzymes have already been mentioned, so 

 I shall limit my discussion to those non-oxidative enzymes of spore 

 extracts with which I have had recent personal experience. This 

 limitation, you will discover, is very confining. 



It is not unlikely that some of these enzymes may actually exist in an in- 

 active condition within the spore, and that the process of grinding, etc., in- 

 volved in preparation of extracts entirely distorts the true picture of the 

 state of affairs within the spore. This warning should temper considerably 

 your gullibility in accepting any theory which I may propound. Further- 

 more, you must realize that the evidence for some of these theories is far 

 from overwhelming. Indeed, I am most grateful for this opportunity to 

 speak more or less irresponsibly on a subject over which I have been mull- 

 ing for some time. I have a great many slides but since each will appear only 

 briefly, I trust you will bear with them. 



In spite of the low metabolic activity of the spores, we felt rather early 

 in our work that spores, as living things, must have some enzymes. One of 

 the first enzymes with which we worked was the glutamic-aspartic transa- 

 minase of Bacillus megaterium spore extracts (Levinson and Sevag, 1954a). 

 This enzyme (catalyzing the reaction: a-ketoglutarate -\- aspartate ±^ gluta- 

 mate -|- oxalacetate) was estimated by the measurement of oxalacetate 

 production (Fig. 1). Briefly, the main finding was that, on a mg protein N 

 basis, the glutamic-aspartic transaminase was as active in extracts of spores 

 as in vegetative cell extracts of B. megaterium. 



This finding — that is, the mere presence of enzyme in the spores — encour- 

 aged us to go on. However, before proceeding with the story, I must back- 

 track somewhat. Some of you may recall that we had shown a stimulation 

 of germination and respiration of B. megaterium spores by manganous ion 

 (Fig. 2). Incidentally, this figure gives an indication of the close relation- 

 ship between germination, respiration, and turbidity of spore suspensions. 

 Cobalt and zinc also had a stimulating effect on germination and respira- 

 tion, but other cations, such as Mg++, Ca++, Cu++, and Fe++ did not 

 (Levinson and Sevag, 1953). 



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