Dominant Negative RWA Mutants for Precise Xylan Acetylation Control

The patent applies local quality by using cell-type-specific promoters (such as secondary wall-specific promoters) to drive the expression of dominant negative RWA mutants only in specific cell types where secondary walls are present. This enables precise spatial control of acetylation reduction, modifying only the cell walls of target cells (e.g., fiber cells, vessel elements) while leaving other cell types unaffected, thereby achieving high manufacturing precision in acetylation modification.

The patent applies parameter changes by introducing specific amino acid substitutions in the RWA protein sequence (such as changes in the catalytic domain) that alter the enzymatic activity parameter. The dominant negative mutants contain mutations that reduce or abolish their own acetyltransferase activity while simultaneously interfering with wild-type RWA proteins through dimerization or complex formation. This parameter change in protein function achieves reduced xylan acetylation and improved sugar yield during biomass pretreatment.