| Comments |
P.5 left column bottom paragraph: "While in silico there is no difference in energy yield for M. pneumoniae grown on different carbon sources (assuming the same amount of carbon taken up for each sugar source, Supplementary information), in vivo the doubling times differed significantly and only glucose and mannose allowed robust growth (Yus et al, 2009). This apparent discrepancy can be explained by the abundances of the respective uptake and processing systems. While the glucose‐specific uptake protein (MPN207) has high copy numbers (∼385/cell), the known transport proteins for other sugars (fructose, ribose, ascorbate, mannitol, mannose, glycerol, and G3P) are 8–20 times less abundant (Maier et al, 2011 PMID 21772259). In fact, to allow relevant growth of M. pneumoniae on fructose in vivo the cells had to be adapted over several serial passages and showed significant overexpression of the proteins involved in fructose import and metabolism (Yus et al, 2009)." |