Figure 5
CTEM images of magnetosomes during in situ heating experiment when subjected to 150 °C until 500 °C and exposed to Ar and O2. From (A) to (C) in irradiation condition, (A) CTEM image of a chain of magnetosomes at 150 °C with Ar; (B) CTEM image of the same chain shown in (A) after heating to 300 °C and exposed to O2; (C) CTEM image of the same chain shown in (B) after heating to 500 °C and exposed to O2 and irradiated by the electron beam; (D) CTEM image of magnetosomes at 500 °C exposed to O2 obtained in a region that has not been irradiated by the electron beam. Note that the general shape of the magnetosome is maintained, but cavities occur in some crystals. (E) Enlarged image of the boxed area in Fig. D (see also the supplementary Fig. S3) showing a cavity in the magnetosome structure. Inset shows the FFT corresponding to this high-resolution image. The corresponding zone axis can be assigned to magnetite or maghemite but also to a mixed structure (see also Supplementary Fig. S5).
