Abstract
Spectrophotometric assay of ribulose 1, 5-bisphosphate carboxlase, Rubisco, is a very useful method for the routine determination. However, when the freshly synthesized ribulose 1, 5-bisphosphate, RuBP, is used as substrate there is a lag time between the carboxylation and NADH oxidation in the assay. In this study, we found firstly that the lag time was closely related to thc concentrations of phosphoglycerate kinase, PGK, glyceraldehyde 3-phosphate dehydrogenase, GAP-DH, and phosphocreatine kinase, PCK, in the assay mixture. After increasing thc concentrations of the coupling enzymes of PGK and GAP-DH, the lag time was shortened, but could not be eliminated completely. By increasing the concentration of PCK, lag time decreased significantly until there was no lag time. So, to overcome the lag time, the key is to increase the use of PCK but not the coupling enzymes. In addition, the accumulation of ADP in the assay mixture proved to be the most important factor in the assay mixture that produced the lag time in the spectrophotometric assay, and an optimum condition for activation and catalysis of Rubisco were also established. With the assay conditions established, high initial and total Rubisco activities were obtained.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
