Sequence alignment of the upstream regions of Methanosarcina mtaA1, mtaA1, and mtbA genes. A sequence of approximately 60 bp of DNA upstream of the predicted start site of the M. acetivorans (Ma), M. barkeri (Mb), and M. mazei (Mm) mtaA1 gene (A), mtaA2 gene (B), and mtbA gene (C) was compared using CLUSTALW (42). The predicted start codon for each gene is shown in cyan. The putative RBS is shown in yellow. (A) Conserved bases are shown in red. The annotated start site is underlined. (B) Conserved bases are shown in green. (C) Bases conserved in all three Methanosarcina spp. are shown in blue while those conserved in M. acetivorans and M. mazei are shown in red.