Alignment of RT amino acid
sequences. One example sequence is shown for each of the major phylogenetic
groupings (mitochondrial, algal, bacterial and euglenoid; see Fig.
3). Below each example sequence is the consensus sequence for that
group, defined as the positions conserved in at least 75% of
the members. The overall consensus is presented above the alignment,
and is defined as residues common to the mitochondrial, algal and
bacterial consensus sequences. Domains 0–7, X and Zn are
marked as described in the text. The locations of spacers between
RT domains 4 and 5 and between domains 7 and X are indicated (see text
and Fig. 3). Residues marked in bold are consensus sequence positions
specific to one group. In cases of closely related sequences (e.g.
plant nad1I4 introns), only one example was included
in the consensus sequence calculation. Sequences used in the calculation
were: mitochondrial group (Z.m.nad1I4, M.p.cox1I1, M.p.cob1I3, M.p.atpAI1, M.p.atpAI2, S.c.cox1I2, S.c.cox1I1, M.p.atp9I1, S.p.cox2I1, S.p.cox1I1, A.m.cox1I3, P.a.cox1I4, M.p.SSUI1, P.a.cox1I1, S.a.1, L.l., S.p.cob1I1, V.i.cob1I1, P.li.cox1I3, P.a.ND5I4, M.p.ORF732, M.p.cox1I2, P.li.cox1I2, P.li.cox1I1, N.c.cox1I1 and M.p.cox2I2); algal group (P.p.LSUI1, C.s., B.m.rbcLI1, B.a.-07, S.o.petDI1, P.li.LSUI1, P.li.LSUI2, P.s. and E.c.-0157); bacterial
group (S.f., S.p., P.a., B.m., C.d., B.a.-23, S.me., B.h. and E.c.B);
and euglenoid group (E.v.psbCI4, A.l.ORF456, E.g.psbCI4, E.d.psbCI4, L.b.psbCI4, E.m.psbCI4 and P.s.cpn60I1).