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THE FORMATION OF SPORES 

 BY BACTERIA* 



H, Orin Halvorson 



UNIVERSITY OF ILLINOIS 



Our interest in the bacterial spore problem has been motivated by a 

 desire to gain an insight into the mechanism whereby spores obtain 

 their resistance to heat and other unfavorable environmental conditions. 

 The work reported here is directed toward this through a study of some 

 of the biochemical changes that take place during sporogenesis. This 

 approach is a rather recent attack, since in all of our former work we 

 attempted to cast light on the problem through a study of germination 

 and related problems. In this new work, we have taken advantage of 

 findings in other laboratories and our own work on germination and 

 enzyme studies. A brief review is therefore desirable to understand the 

 logic behind the experiments. 



Three crucial observations have, in my opinion, stimulated many 

 of the recent researches on spores. One was the observation by Hills 

 ( 1949 ) that spores will germinate rapidly in the presence of a mixture 

 of amino acids and nucleosides; another was the discovery in our lab- 

 oratory that spores contain active heat-resistant enzymes ( Stewart and 

 Halvorson, 1953; Lawrence and Halvorson, 1954; Nakata, 1956); the 

 third was the observation by Powell (1953) that dipicolinic acid 



" This investigation icas supported by grants from the Office of Naval Re- 

 search and the National Institutes of Health. The results reported herein should 

 not be credited to any one individual but to a research team in which the following 

 have been my co-workers: Dr. Krishnamurty Gollakota, Research Associate and 

 Assistant Professor of Research; Dr. Robert Collier and Dr. Herbert Nakata, for- 

 mer graduate students who have completed research for their theses on some 

 phase of this problem; Ivan Goldberg and John DePinto, current graduate stu- 

 dents; Francis Engle, laboratory assistant; and Mrs. Leena Nara^imhan, research 

 assistant. These individuals are to be considered as co-authors. 



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