Inhibition of phosphoenolpyruvate carboxylase from maize by 2-phosphoglycollate

✍ Scribed by Narendra Jawali; Anil S. Bhagwat

• Book ID: 104614656
• Publisher: Springer
• Year: 1987
• Tongue: English
• Weight: 269 KB
• Volume: 11
• Category: Article
• ISSN: 0166-8595
• DOI: 10.1007/bf00018273

✦ Synopsis

The phosphoenolpyruvate carboxylase from maize leaf was strongly inhibited by 2-phosphoglycollate. The pH of the reaction did not influence the extent of inhibition by 2-phosphoglycollate. The kinetic analysis of the inhibition data by Lineweaver-Burk method showed that 2-phosphoglycollate inhibition was competitive with respect to phosphoenolpyruvate. The secondary plot of the data showed nonlinearity indicating that there may be two 2-phosphoglycollate binding sites with Ki values of 0.4mM and 0.16mM. The biphasic nature of the inhibition was also evident when the data were plotted using the method of Dixon. 2-phosphoglycollate inhibition was uncompetitive with respect to Mg 2+ suggesting that it binds only to enzyme-Mg 2+ complex.