| an attachment tip and pili-like structures in insect- and plant-pathogenic spiroplasmas of the class mollicutes. | ultrastructural studies using scanning electron microscopy (sem), negative-staining transmission electron microscopy (tem), and thin-sectioning tem on four species of spiroplasma, in vitro and/or in vivo, indicated that their helices commonly possess one tapered end (tip structure) and one blunt or round end. these tip structures appeared morphologically different from the rest of the helix, exhibiting an electron-dense conical or rod-shaped core. in thin sections of the midgut of the leafhopper ... | 2004 | 14673515 |