920241.fig.002a
(a)
920241.fig.002b
(b)
920241.fig.002c
(c)
920241.fig.002d
(d)
Figure 2: Ultrathin sections of Methanosarcina mazei (DSM 3318, formerly Methanosarcina frisia (a, b) and Methanococcus maripaludis (c, d) grown on media without nickel depletion. Immunolabeled cells (b, d; a, c are negative controls) show cytoplasmic localization of MCR. The inset in (b) shows an enlarged area of the image before (open star symbol) and after processing (closed star) of the gold marker.