Altered Rubisco activity and amounts of a daytime tightbinding inhibitor in transgenic tobacco expressing limiting amounts of phosphoribulokinase

Abstract

Transgenic tobacco with RuBP-limited photosynthetic assimilation due to a 95% reduction in phosphoribulokinase activity, had higher specific activities of Rubisco in fresh extracts and after full activation, than in the wild type. Differences in the amounts of a daytime tight-binding inhibitor were sufficient to contribute significantly to these activity differences.