Fig. 4.10 Bacteria, suspected or proven, to be involved in the biomineralization of nodules. (a)
Uncultured aquabacterium, isolated from the polymetallic nodule. Alignment of the partial 16S
ribosomal RNA gene sequence from the Mn-nodule (AQbac_NOD1_D), studied by us, with
the corresponding bacterial 16S RNA gene sequence from soil bacterial communities
(AQbac_EF4928; accession number EF492894; He et al. 2008). Identical nucleotides are in
inverted type and those different between the sequences in black on white. (b) Sequence relationship of the mnxG gene (termed mnxG-SubDo-03) [encoding the bacterial multicopper oxidase-like
enzyme], identified in the Bacillus-related strain, isolated from the demosponge S. domuncula. The
deduced polypeptide, MnxG-SubDo-03, was compared with the MnxG proteins from the following Bacillus strains: strain PL-12 (MnxG-PL-12; ABP68890.1), strain GB02-31 (MnxG-GB02-31;
AAZ31744.1), strain GB02-30 (MnxG-GB02-30; AAZ31743.1), strain GB02-27 (MnxG-GB0227; AAZ31742.1), strain GB02-25 (MnxG-GB02-25; AAZ31741.1), strain GB02-16 (MnxGGB02-16; AAZ31739.1), strain GB02-14C (MnxG-GB02-14C; AAZ31738.1), strain GB02-8B
(MnxG-GB02-8B; AAZ31736.1), strain SD-18 (MnxG-SD-18; AAL30449.1), strain GB02-8B
(MnxG-GB02-8B; AAZ31736), and strain GB02-2A (MnxG-GB02-2A; AAZ31735.1). These
4 Biogenic origin of nodules and crusts
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