Biosynthetic enzymes analysis

Yoganathan, A., Isolation, expression and functional analysis of a cDNA encoding phytoene desaturase, a carotenoid biosynthetic enzyme from rice, Oryza sativa L., PhD dissertation. Graduate School and University Center, City University of New York, 1998. 

The second area worthy of comment is with regard to assignment of enzyme function based on amino acid sequence alone. In some cases sequence comparisons can be used to determine if a new cDNA encodes one of the well-known flavonoid biosynthetic enzymes. However, in some cases, sequence similarity is insufficient for reliable prediction of the encoded function. For example, the OMTs may have amino acid identities of above 85% but different activities. For transcription factors such sequence-based assignments of function are significantly more difficult, as specific roles for a given factor may have arisen in particular species. Thus, analysis of genetic mutants and transgenic overexpression or knockout lines is still preferable for confirmation of the encoded activities. 

Winter, J., Schneider, B., Meyenburg, S., Strack, D. and Adam, G. (1999) Monitoring brassinosteroid biosynthetic enzyme by fluorescent tagging and HPLC analysis of their substrates and products. Phytochemistry, 51, 237-42. 

Coenzyme A (CoA) is a cofactor that has been estimated to be used by about 4% of all enzymes, although more recent analysis of the BRENDA database (http //www.brenda.uni-koeln.de/) suggests the number may be closer to 9% (1). The biochemical pathways and processes involving CoA thioesters are diverse and widespread, whereas the kinds of reactions involved primarily follow the inherent reactivity of the thioester functionality. This article provides a brief overview of CoA biosynthesis and a summary of the common types of reactions of CoA thioesters. Also presented is a brief introduction to structural studies and a more extensive description of some types of analogs of natural CoA thioesters that have been employed as mechanistic probes for CoA using enzymes. The application of CoA derivatives and CoA biosynthetic enzymes for the tagging of carrier proteins and carrier protein fusions is also described. 

Lovenberg, S. Walter, and Engelman, Karl, Serotonin The Assay of Hydroxyindole Compounds and Their Biosynthetic Enzymes Loveridge, B. A., and Smales, A. A., Activation Analysis and Its... 

Today more and more of complex biosynthetic reactions are carried out with immobilized whole cells than with immobilized purified enzymes (, 7, 8,9). However, in the field of enzymic analysis, where the use oJ immobilized enzymes is best established, purified enzymes are still used (10,11,12). 

Makiuchi T, Annoura T, Hashimoto T, Murata E,. Aoki, Nara T. Evolutionary analysis of synteny and gene fusion for pyrimidine biosynthetic enzymes in Euglenozoa an extraordinary gap between kinetoplastids and diplonemids. Protists 200 159 459-470. 

---