11-05: Lignin and ABC transport modification to reduce recalcitrance

Lignin down regulation and modification is a popular target when working to alter plant cell walls to lower recalcitrance to processing.  Brief insights will be presented into the usefulness of different lignin modifications.  These have been gained through our work on lignin modified plants (alfalfa, eucalyptus and switchgrass).  The possibility of manipulating ABC transporters to reduce cell wall composition and therefore recalcitrance will then be discussed.  ABC transporters are a very large and varied enzyme family (129 in Arabidopsis) which control the transport of a wide variety of compounds across plant cell membranes and have recently been implicated in transport of lignin across the plant cell wall.  Working with collaborators who had developed a range on ABC knock outs in Arabidopsis, we have found that removal of many of the enzymes causes plant cell wall compositional changes, resulting in reduced recalcitrance to pretreatment.  Results so far will be discussed.