Creation and analysis of chimeras of spinach and tobacco Rubisco activase

Ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco: EC 4.1.1.39) catalyzes the initial step in photosynthesis, by combining CO$\sb2$ with ribulose bisphosphate to form two molecules of PGA. Rubisco activase is a protein which regulates the activity of Rubisco in vivo and hydrolyzes ATP. Regulation is achieved by promoting carbamylation of Rubisco (required for catalytic activation) as well as freeing Rubisco of various other sugar phosphates which either interfere with carbamylation or diminish the activity of carbamylated enzyme. Previously spinach Rubisco activase had been cloned into the pPlex expression vector and the resulting polypeptide purified and characterized. I modified this clone to obtain protein truncated at the N and C terminus. Truncation at the N terminus had no effect until a conserved tryptophan was removed. Deletion of this residue reduced Rubisco activation with no effect on ATP hydrolysis. Truncation of the C terminus, on the other hand, had no effect on ATP hydrolysis but rather increased Rubisco activation. It was concluded that the ratio of Rubisco activation to ATP hydrolysis, the efficiency of activation, could be altered by modification of the Rubisco activase polypeptide.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Biology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Esau, Brian Daniel

Contributors dc:contributor

• Portis, A.R.

• Biology, Plant Physiology

Statement dc:rights

• Copyright 1996 Esau, Brian Daniel

Language dc:language

eng

Identifier

AAI9625131
(UMI)AAI9625131

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/21518