Fig. 6.

Phylogenic tree showing the evolutionary relationships among invertases, fructan exohydrolases, and fructosyltransferases. Each node with descendants represents the most recent common ancestor of the invertases, and the branch lengths are proportional to the amount of inferred evolutionary change and thus correspond to time estimates. Arrowheads indicate anther-specifically expressed cell wall-bound invertases. CwINVs, cell wall-bound invertases; vacINVs, vacuolar invertases; cytINVs, cytoplasmic invertases; FEHs, fructan exohydrolases; FBEs, fructan-building enzymes. For abbreviations and references for the single coding sequences of the different species see Materials and methods; the number at the end of the abbreviation indicates the pI value of the corresponding protein.