Fig. 5
a The ntp Vacuole-type ATP synthase operon structure. b 93 ntpD homologs (DealDRAFT_1677) within the genus Clostridia were aligned in Clustal Omega [34] and an unrooted neighbour-joining tree was generated in MEGA-6 [49]. From this tree, we picked the branch that contained the D. alkaliphilus AHT1T ntpD sequence and computed a new neighbourjoining tree with gene DCR20291_1119 as an outgroup. The scale bar indicates a 0.5% sequence difference and conserved gene neighbourhoods of those genes were investigated using MGcV [50]. Large dots at the tree nodes indicate a bootstrap value of >85 (1000 replicates)