BIOMOLECULAR ASPECTS OF SPERMATOZOAN MOTILITY 199 



1956). The pattern consistently obtained from flagella from a number 

 of sources is of protein without any indication so far of the muscle 

 type configuration (Pautard, 1958b). 



Attempts to orient films of algal flagella by stretching have met with 

 little success, probably because of the extensive disruption of both 

 cells and flagella during preparation. In the case of fish sperm flagella, 

 however, well-oriented x-ray diffraction patterns have been obtained 

 from perch sperm flagella and particularly from more recent prepara- 

 tions of trout sperm flagella where buffered salt solutions have been 

 used and the films have been carefully stretched and examined in moist 

 air. The diffraction pattern (Fig. 4a) is characterized by a number of 

 low-angle equatorial and near reflections (Fig. 4b and Table I) and a 

 diffuse ring at 4-5 A with denser areas near the meridian. These spac- 

 ings are strongly reminiscent of phospholipids, and the diffraction pat- 

 tern from trout sperm flagella does, in fact, closely resemble that from 

 trout spinal cord (shown for comparison in Fig. 4c). When the films of 

 flagella were treated with ether or other solvents, the "phospholipid" 

 pattern disappeared. The underlying diffraction pattern was usually 

 of unoriented protein, but from time to time stretched films of fla- 

 gella prepared in buffered salt solutions and extracted with ether 

 after drying showed the reflection at 4.65 A on the meridian, charac- 

 teristic of the cross-/} configuration, together with another familiar, 

 sharper arc at about 4.1 A, characteristic of lipid. A diagram of this 

 type from trout sperm flagella is shown in Fig. 4d. 



Table I. Low-angle reflections from flagella, equatorial and near reflec- 

 tions 



Perch Sperm Flagella' 1 Trout Sperm Flagella 1 ' 



(A) (A) 



9 . 6 MS diffuse 9 . 4 M diffuse 



16. 7M 10. 7M 



36.3 W 12.9 M 



44.0 VS 16.0 S 



82.0 VS 22.1 VW 



35.0 VS diffuse 



° M, medium; W, weak; S, strong; VS, very strong; VW, very weak; MS, medium 

 strong. 



'' Specimen-to-film distance, 6 cm. 

 c Specimen-to-film distance, 4 cm. 



