User:Sujay Joseph/Sandbox1 Choline Oxidase

From Proteopedia

Threonine 463, valine 464, and histidine 466 are evolutionarily preserved(the amino acid sequences are the same)from bacteria to mice in an enzyme that changed drastically. We found that the significant amino acids are Histidine 466,Valine 464, Threonine 463 that are 4.09 Å,5.07 Å,7.67 Å respectively from the active site. Each of the three residues should therefore be of some importance to the stability of the flavin group, seeing as they were evolutionarily conserved. It is evident that His466 acts as a base in the active site of choline oxidase (Chen and Murata, 2002). However, the functions of Thr463 and Val464 are unknown. Therefore, further research would be necessary to determine the functions of all of the amino acids lining the active site. Mutational studies will also help a great deal in our understanding of the enzyme to see what effect mutating any combination of these three amino acids would have on the enzymatic activity of choline oxidase. Knowing the functions of the amino acids in the active site will enable us to devise genetically modified choline oxidase enzymes. If any recombinant enzymes are found to be Were any recombinant enzymes found to be functionally better, then they could be introduced to a population of plants to genetically induce potential resistance to drought. On the other hand, recombinant choline oxidase enzymes that were catalytically slower could be studied for their effect on reducing, if not completely suppressing, the growth of pathogenic bacterial colonies.

Works Cited

Altschul SF, Wootton JC, Gertz EM, Agarwala R, Morgulis A, Schäffer AA, and Yu YK (2005). Protein database searches using compositionally adjusted substitution matrices. FEBS J. 272, 5101-5109. Chen TH and Murata N. (2002). Enhancement of tolerance of abiotic stress by metabolic engineering of betaines and other compatible solutes. Curr. Opin. Plant Biol. 5, 250-257 Joosten V and van Berkel WJH. (2007). Flavoenzymes. Current Opinion in Chemical Biology, 11:195–202 ncbi.org. (2009). Retrieved November 20, 2009, from Protein Databank: www.ncbi.org Quaye, O., Lountos, G., Fan, F., Orville, A., & Gadda, G. (2008). Role of Glu312 in Binding and Positioning of the Substrate for the Hydride. Biochemistry, 47, 243-256. Rodwazowski KL, Khachatourians GG, and Selvaraj G. (1990). Choline oxidase, a catabolic enzyme in Arthrobacter pascens, facilitates adaptation to osmotic stress in Escherichia coli. J Bacteriol. 173(2), 472-478 Sakamoto A and Murata N. (2001). The Use of Bacterial Choline Oxidase, a Glycinebetaine – synthesizing Enzyme, to Create Stress-Resistant Transgenic Plants1. Plant Biology Vol. 125, pp. 180–188