Figure 4

Transmission electron microscopy analysis of semen and synthetic SEVI in a closed system. A fresh semen sample and a solution of chemically synthesized SEVI (PAP-fragment PAP248-286) were analyzed as described in the methods section. The bottom images depict a detail (magnification: 35,000 ×) of the above electron micrographs (magnification: 6,300 ×). The semen sample shows a high density of fibrils with lengths ranging from 300 nm to about 3 μm, that exhibit a clear resemblance to the fibrils formed from chemically synthesized SEVI (PAP-fragment PAP248-286). The synthetic SEVI fibrils frequently run out of pane due to the embedding angle. Arrows indicate typical fibril structures.