| 研究生: |
盧昱穎 Yu-Ying Lu |
|---|---|
| 論文名稱: |
導引式演化細胞色素P450 BM3做為辛烷次末端之羥基化酵素 The Random Mutagenesis Studies of Cytochrome P450 BM3 for Regioselective C-2 Activation of Octane |
| 指導教授: |
蔡惠旭
Hui-Hsu Gavin Tsai 俞聖法 Steve, Sheng-Fa Yu |
| 口試委員: | |
| 學位類別: |
碩士 Master |
| 系所名稱: |
理學院 - 化學學系 Department of Chemistry |
| 畢業學年度: | 96 |
| 語文別: | 中文 |
| 論文頁數: | 252 |
| 中文關鍵詞: | 細胞色素 、羥基化酵素 、辛烷 、導引式演化 |
| 外文關鍵詞: | Octane, Regioselective, Cytochrome P450, Random Mutagenesis |
| 相關次數: | 點閱:8 下載:0 |
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由文獻可知Bacillus megaterium的細胞色素P450 BM3對其天然受質脂酸酸具有高度的專一性。我們成功的以大腸桿菌表現細胞色素P450 BM3,並且將random mutation P450序列以PCR複製載體或序列直接嵌入載體的方法,在不改變P450 reductase序列的情況下,探討三個定點突變(Ala74Gly, Phe87Val, Leu188Gln)與random mutation後P450蛋白質序列改變對辛烷催化反應的影響。
我們也利用iodoform reaction氧化在次末端具有羥基的2-octanol,並以GC或UV-Visible Spectroscopy分析氧化後的產物,建立可靠且快速檢測細菌氧化辛烷次末端碳氫鍵的轉化率的方法。
另一方面,我們也將Pseudomonas putida中參與camphor氧化的細胞色素P450cam (CamC)與電子傳遞的蛋白質Putidaredoxin (CamB)的序列,成功嵌入載體,並以E. coli表現出Putidaredoxin (CamB)蛋白質。
It was known that the Bacillus megaterium Cytochrome P450 BM3 exhibits high substrates specificity to catalyzing its congenital substrates, fatty acids. In this study, cytochrome P450 BM3 proteins were successfully heterologously expressed in Escherichia coli. A mutated Ala74Gly, Phe87Val, and Leu188Gln strain was also validate for octane oxidation. After employing random mutation studies of the P450BM3 encoded sequences, we obtained the other three variants to study their octane activation chemistry without any alteration of P450 reductase encoded sequences.
2-octanol exhibiting a hydroxyl group at the sub-terminal carbon could be further oxidized via the iodoform reaction. The oxidation products were analyzed by GC and UV-visible Spectroscopy. The conversion ratio of C-H bond on the 2nd carbon of octane by bacteria could be quantities facilely and reliably. We anticipate deploying this method for selecting appropriate strains to achieve the C-H activation of sub-terminal hydrocarbon in more specific manner.
In addition, the DNA of Pseudomonas putida Cytochrome P450cam (CamC) and Putidaredoxin (CamB) encoded sequences involved with the functions on camphor hydroxylation and catalytic redox suppliers, respectively, were constructed within the protein expression vectors pET 21a and 22b. Those constructed vectors were successfully transformed into the host, E. coli BL21 (DE3). The Putidaredoxin (CamB) protein could be expressed in E. coli heterlogously in the presence of IPTG.
1. 洪惠瑩, Utilization of Cytochrome P450 BM3 as the Biocatalysts for Aliphatic Compounds Activation, in Department of Chemistry. 2007, National Cheng Kung University: Tainan.
2. Encyclopedia of Life Sciences. 2005 [cited; Available from: www.els.net.
3. Denisov, I.G., et al., Structure and chemistry of cytochrome P450. Chem Rev, 2005. 105(6): p. 2253-77.
4. Peters, M.W., et al., Regio- and enantioselective alkane hydroxylation with engineered cytochromes P450 BM-3. J Am Chem Soc, 2003. 125(44): p. 13442-50.
5. Poulos, T.L., The past and present of P450cam structural biology. Biochem Biophys Res Commun, 2003. 312(1): p. 35-9.
6. Shaik, S., et al., Theoretical perspective on the structure and mechanism of cytochrome P450 enzymes. Chem Rev, 2005. 105(6): p. 2279-328.
7. Hartline, R.A. and I.C. Gunsalus, Induction specificity and catabolite repression of the early enzymes in camphor degradation by Pseudomonas putida. J Bacteriol, 1971. 106(2): p. 468-78.
8. Novagen.
9. Stratagene, GeneMorph® II EZClone Domain Mutagenesis Kit
INSTRUCTION MANUAL.
10. Glieder, A., E.T. Farinas, and F.H. Arnold, Laboratory evolution of a soluble, self-sufficient, highly active alkane hydroxylase. Nat Biotechnol, 2002. 20(11): p. 1135-9.
11. Farinas, E.T., et al., Directed evolution of a cytochrome P450 monooxygenase for alkane oxidation. Advanced Synthesis & Catalysis, 2001. 343(6-7): p. 601-606.
12. Mouri, T., et al., A recombinant Escherichia coli whole cell biocatalyst harboring a cytochrome P450cam monooxygenase system coupled with enzymatic cofactor regeneration. Appl Microbiol Biotechnol, 2006. 72(3): p. 514-20.
13. Speight, R.E., et al., Rapid identification of cytochrome P450(cam) variants by in vivo screening of active site libraries. Tetrahedron-Asymmetry, 2004. 15(18): p. 2829-2831.
14. Sibbesen, O., J.J. DeVoss, and P.R.O. deMontellano, Putidaredoxin reductase-putidaredoxin-cytochrome P450(cam) triple fusion protein - Construction of a self-sufficient Escherichia coli catalytic system. Journal of Biological Chemistry, 1996. 271(37): p. 22462-22469.
15. Dalnogare, S., T.O. Norris, and J. Mitchell, Determination of Acetaldehyde and Acetone by the Iodoform Reaction - Determination of 1,2-Propylene Glycol. Analytical Chemistry, 1951. 23(10): p. 1473-1478.
16. Hunter, R.F., A.M. Qureishy, and R. Samuel, The problem of chemical linkage - Part II The absorption spectra of some dipole association products. Journal of the Chemical Society, 1936: p. 1576-1580.
17. Joo, H., et al., A high-throughput digital imaging screen for the discovery and directed evolution of oxygenases. Chem Biol, 1999. 6(10): p. 699-706.
18. Rui, L., S.S. Pochapsky, and T.C. Pochapsky, Comparison of the complexes formed by cytochrome P450cam with cytochrome b5 and putidaredoxin, two effectors of camphor hydroxylase activity. Biochemistry, 2006. 45(12): p. 3887-97.
19. Appel, D., et al., A P450 BM-3 mutant hydroxylates alkanes, cycloalkanes, arenes and heteroarenes. J Biotechnol, 2001. 88(2): p. 167-71.
20. Unger, B.P., I.C. Gunsalus, and S.G. Sligar, Nucleotide sequence of the Pseudomonas putida cytochrome P-450cam gene and its expression in Escherichia coli. J Biol Chem, 1986. 261(3): p. 1158-63.
21. Ta, D.T. and L.E. Vickery, Cloning, sequencing, and overexpression of a [2Fe-2S] ferredoxin gene from Escherichia coli. J Biol Chem, 1992. 267(16): p. 11120-5.
22. Knoell, H.E. and J. Knappe, Escherichia coli ferredoxin, an iron-sulfur protein of the adrenodoxin type. Eur J Biochem, 1974. 50(1): p. 245-52.
23. Gunsalus, I.C. and G.C. Wagner, Bacterial P-450cam methylene monooxygenase components: cytochrome m, putidaredoxin, and putidaredoxin reductase. Methods Enzymol, 1978. 52: p. 166-88.
24. Peterson, J.A., M.C. Lorence, and B. Amarneh, Putidaredoxin reductase and putidaredoxin. Cloning, sequence determination, and heterologous expression of the proteins. J Biol Chem, 1990. 265(11): p. 6066-73.
25. Ichinose, H., et al., Electron-transfer reactions and functionalization of cytochrome P450cam monooxygenase system in reverse micelles. Langmuir, 2004. 20(13): p. 5564-8.
26. DeVoss, J.J., et al., Substrate docking algorithms and prediction of the substrate specificity of cytochrome P450(cam) and its L244A mutant. Journal of the American Chemical Society, 1997. 119(24): p. 5489-5498.