Studies on Isolated Flagella"* 



C. J. BROKAWf 



Zoology Department, University of Minnesota, Minneapolis, Minnesota 



At the present state of our knowledge, there is little reason to divorce 

 the problem of spermatozoan motility from the general problem posed 

 by the rhythmic, propagated bending waves found in all types of fla- 

 gella. In approaching this general problem, the flagella of the orange, 

 binagellate alga, Polytoma uvella, offer some advantages. The algae 

 can be grown in quantity in any geographical location and at any time 

 of the year. Their flagella have an uncomplicated ultrastructure simi- 

 lar to that of the simplest appearing spermatozoa, such as those of the 

 sea urchin. There is a clear distinction between the flagella and the 

 remainder of the cell which supplies the flagella with sources of chemi- 

 cal energy, so that simple techniques have been developed for prepar- 

 ing clean fractions of isolated flagella. One of these isolation tech- 

 niques (Brokaw, 1961) involves a relatively gentle treatment similar 

 to that introduced by Hoffmann-Berling (1955) for the preparation of 

 sperm models. The isolated flagella can be stored in glycerol solutions 

 at — 20°C and can then be reactivated to a high degree when placed in 

 appropriate solutions containing ATP. With flagella prepared in this 

 way, biochemical studies and studies of movement can be carried out 

 on the same material under the same conditions. 



The limited amount of biochemical work carried out with this ma- 

 terial to date has been described elsewhere (Brokaw, 1961) and will 

 only be summarized briefly before turning to a consideration of some 

 aspects of the movement of the isolated flagella. The ATPase activity 

 of Polytoma flagella was first demonstrated by Tibbs (1957), using an- 

 other type of preparation. With preparations containing intact fla- 



* This work has been supported by research grants from the National Institutes 

 of Health, United States Public Health Service (RG-7208), and the Graduate 

 School of the University of Minnesota. 



f Present address: Division of Biology, California Institute of Technology, 

 Pasadena. 



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