Figure 2-5: Selected isometric and filamentous phages. (a) E. coli microvirus ?X174, x 297,000. (b) Tectivirus 37-64 of Thermus sp., note inner membrane and deformed particles; x 297,000. E. coli levivirus R17 adsorbed to pili, x 148,500. Inovirus H75 of Thermus thermophilus, x 92,400. Bars indicate 100 nm. Uranyl acetate (a) and phosphotungstate (b, c).