PARENT SESSION
Posters P3C C3 and Rubisco. Abstracts (617-630)

Reconstitution of tobacco Rubisco from a fully denatured subunits with the help of Chaperonin 60 in vitro. Zhen Hua Yong¹, Gen-Yun Chen ^*,2, Da-Quan Xu³, ¹ 300 Fengling Road, Shanghai, China² 300 Fengling Road, Shanghai, China³ 300 Fengling Road, 200032, China

ABSTRACT- The main obstacle of reconstitution from fully denatured Rubisco subunits in vitro is the aggregation of Rubisco large subunit when the denaturant was removed by a direct dilution or one-step dialysis. This problem was resolved by gradual dialysis so that the concentration of detergent was decreased gradually in reassembly assay, However, fully denatured Rubisco still could not be assembly into holoenzyme after gradual dialysis unless the Chaperonin 60 was added in assembly as native PAGE analysis showed. The suitable incubation temperature for Rubisco reassembly in vitro was at 25-35^oC, and the time for reassembly was in 2 h. The restoration activity of reassembled Rubisco was approximately 10% of nature enzyme. The processing of reassembly from fully denatured Rubisco subunits was inhibited by Mg²⁺, but was promoted when ATP and Mg²⁺ presented in assay. The assembly processing was weakened when all of ATP, Mg²⁺ and K⁺ were presented in reassembly assay because of the dissociation of cpn 60.

KEY WORDS: cpn 60, Rubisco, Reassembly