BMC Genomics 2005, 6:136 http://www.biomedcentral.com/1471-2164/6/136 PFyigriumriedi2ne-purine walks of mitochondrial genome (+) strands of selected species Pyrimidine-purine walks of mitochondrial genome (+) strands of selected species. M, S, and R indicate membrane protein-coding, soluble protein-coding, and RNA-coding segments, respectively. Single tRNA genes are not shown due to their small size, but stretches of 2 or more consecutive tRNAs on the same strand are shown. The coloring scheme for colors not shown in the legend follows that of Figure 1. Page 4 of 12 (page number not for citation purposes)