The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Purification and characterization of indolepyruvate decarboxylase. A novel enzyme for indole-3-acetic acid biosynthesis in Enterobacter cloacae.

Indolepyruvate decarboxylase, a key enzyme for indole-3-acetic acid biosynthesis, was found in extracts of Enterobacter cloacae. The enzyme catalyzes the decarboxylation of indole-3-pyruvic acid to yield indole-3-acetaldehyde and carbon dioxide. The enzyme was purified to apparent homogeneity from Escherichia coli cells harboring the genetic locus for this enzyme obtained from E. cloacae. The results of gel filtration experiments showed that indolepyruvate decarboxylase is a tetramer with an M(r) of 240,000. In the absence of thiamine pyrophosphate and Mg2+, the active tetramers dissociate into inactive monomers and dimers. However, the addition of thiamine pyrophosphate and Mg2+ to the inactive monomers and dimers results in the formation of active tetramers. These results indicate that the thiamine pyrophosphate-Mg2+ complex functions in the formation of the tetramer, which is the enzymatically active holoenzyme. The enzyme exhibited decarboxylase activity with indole-3-pyruvic acid and pyruvic acid as substrates, but no decarboxylase activity was apparent with L-tryptophan, indole-3-lactic acid, beta-phenylpyruvic acid, oxalic acid, oxaloacetic acid, and acetoacetic acid. The Km values for indole-3-pyruvic acid and pyruvic acid were 15 microM and 2.5 mM, respectively. These results indicate that indole-3-acetic acid biosynthesis in E. cloacae is mediated by indolepyruvate decarboxylase, which has a high specificity and affinity for indole-3-pyruvic acid.[1]

References

 
WikiGenes - Universities