Preparation and Assay of Recombinant Serine Racemase
Serine racemase is a glial and neuronal enzyme that reversibly converts l-serine to d-serine, an endogenous co-agonist of N-methyl-d-aspartate receptor type glutamate receptors (NMDARs). Here we present methods to recombinantly express and purify serine racemase in bacteria and two complementary ways to determine d-serine levels in unknown samples. Furthermore, a detailed protocol of serine racemase activity assays is described that can be used to screen for activators and inhibitors in vitro.
Key wordsSerine racemase d-Serine PLP enzymes Racemization
This work was supported by Grants BFU2006-05395 and BFU2009-10442 from the Spanish MICINN.
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