There was a significantly higher proportion of Gammaproteobacteria in the maize sites than in the other land use types (p < 0.05; Figure 1(a)), with a total of 13 families occurring in the former, among which Chromatiaceae (4.0%), Sinobacteraceae (5.3%), and Xanthomonadaceae (3.0%) were dominant, and Ectothiorhodospiraceae (0.34%) and Halothiobacillaceae (1.6%) were only found here.
The main families within this class were Chromatiaceae, Sinobacteraceae, and Xanthomonadaceae, all of which have been reported as only being found in agricultural soils and not natural grassland and forest soils [21].
The closest cultivable relatives of MONTS members are free-living purple sulfur bacteria (
Chromatiaceae).
Most of the organisms belong to one of two families, the
Chromatiaceae (purple sulphur bacteria) and Chlorobiaceae (green sulphur bacteria).
Such intracellular sulfur vesicles stored as an intermediate during the oxidation of sulfide and thio-sulfate are typical for
Chromatiaceae, the purple sulfur bacteria (Brenner et al, 2005; Dahl and Prange, 2006; Imhoff, 2006), the family to which most of the thioau-totrophic endosymbionts belong (Dubilier et al, 2008).