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| DC 欄位 | 值 | 語言 |
|---|---|---|
| dc.contributor.advisor | 王惠鈞(Andrew H.-J. Wang) | |
| dc.contributor.author | Hui-Ju Chen | en |
| dc.contributor.author | 陳蕙如 | zh_TW |
| dc.date.accessioned | 2021-06-15T02:42:12Z | - |
| dc.date.available | 2012-12-12 | |
| dc.date.copyright | 2009-08-13 | |
| dc.date.issued | 2009 | |
| dc.date.submitted | 2009-08-11 | |
| dc.identifier.citation | Abe K, Ohnishi F, Yagi K, Nakajima T, Sano M, Machida M, Sarker RI, Maloney PC
(2002) Plasmid-encoded asp operon confers a proton motive metabolic cycle catalyzed by an aspartate-alanine exchange reaction. J Bacterial 184 : 2906-2913. Adams B, Lowpetch K, Thorndycroft F, Whyte SM, Young DW. (2005) Stereochemistry of reactions of the inhibitor/substrates L- and D-beta-chloroalanine with beta-mercaptoethanol catalysed by L-aspartate aminotransferase and D-amino acid aminotransferase respectively. Org Biomol Chem. 21, 3357-64 Barton, G.J. (1993). MALSCRIPT: a tool to format multiple sequence alignments. Protein Eng. 6, 37–40. Berman H.M., Westbrook J., Feng Z., Gilliland G., Bhat T.N. and Weissig H. (2000). The protein databank, Nucl. Acids Res. 28, 235–242. Blaesse, M., Kupke, T., Huber, R., and Steinbacher, S. (2000). Crystal structure of the peptidyl-cysteine decarboxylase EpiD complexed with a pentapeptide substrate. EMBO J. 19, 6299–6310. Bowers, W.F., Czubaroff, V.B., and Haschemeyer, R.H. (1970). Subunit structure of L-aspartate beta-decarboxylase from Alcaligenes faecalis. Biochemistry 9, 2620–2625. Brunger, A.T. (1993). Assessment of phase accuracy by cross validation: the free R value. Methods and applications. Acta Crystallogr. D. Biol. Crystallogr. 49, 24–36. Brunger, A.T., Adams, P.D., Clore, G.M., DeLano, W.L., Gros, P., Grosse-Kunstleve, R.W., Jiang, J.S., Kuszewski, J., Nilges, M., Pannu, N.S., et al. (1998). Crystallography and NMR system: a new software suite for macromolecular structure determination. Acta Crystallogr. D. Biol. Crystallogr. 54, 905–921. 62 Brzovic, P., Holbrook, E.L., Greene, R.C., and Dunn, M.F. (1990). Reaction mechanism of Escherichia coli cystathionine γ-synthase: direct evidence for a pyridoxamine derivative of vinylgloxylate as a key intermediate in pyridoxal phosphate dependent γ-elimination and γ-replacement reactions. Biochemistry 29, 442–451. Capitani G., Biase D.D.,, Aurizi C., Gut H., Bossa F., and Grütter G.M. (2003). Crystal structure and functional analysis of Escherichia coli glutamate decarboxylase. EMBO J. 22, 4027-4037. Chang, C.C., Laghai, A., O’Leary, M.H., and Floss, H.G. (1982). Some stereochemical features of aspartate beta-decarboxylase. J. Biol. Chem. 257, 3564–3569. Chen, C.C., Chou, T.L., and Lee, C.Y. (2000). Cloning, expression and characterization of L-aspartate β-decarboxylase gene from Alcaligenes faecalis CCRC11585. J. Ind. Microbiol. Biotechnol. 25, 132–140. Chen, H.J., Ko, T.P., Lee, C.Y., Wang, N.C., and Wang, H.-J. (2009) Structure, assembly, and mechanism of a PLP-dependent dodecameric L-aspartate β- decarboxylase. Structure 17, 517-529. Cheong CG, Escalante-Semerena JC, Rayment I. (2002) Structural studies of the L-threonine-O-3-phosphate decarboxylase (CobD) enzyme from Salmonella enterica: the apo, substrate, and product-aldimine complexes. Biochemistry. 41, 9079-9089. Chibata, I., Kakimoto, T., and Kato, J. (1965). Enzymatic production of L-alanine by Pseudomonas dacunhae. Appl. Microbiol. 13, 638–645. Chibata, I., Kakimoto, T., Kato, J., Shibatani, T., and Nishimura, N. (1967). Crystalline aspartic beta-decarboxylase of Pseudomonas dacunhae. Biochem. Biophys. Res. Commun. 26, 662–667. 63 Churchich JE, Moses U. (1981) 4-Aminobutyrate aminotransferase. The presence of nonequivalent binding sites. J. Biol. Chem. 256, 1101–4 Contestabile R, Paiardini A, Pascarella S, di Salvo ML, D’Aguanno S, Bossa F. (2001) L-Threonine aldolase, serine hydroxymethyltransferase and fungal alanine racemase. A subgroup of strictly related enzymes specialized for different functions. Eur. J. Biochem. 268, 6508–25. Domingo, G.J., Orru’, S., and Perham, R.N. (2001). Multiple display of peptides and proteins on a macromolecular scaffold derived from a multienzyme complex. J. Mol. Biol. 305, 259–267. Dunathan, H.C. (1966). Conformation and reaction specificity in pyridoxal phosphate enzymes. Proc. Natl. Acad. Sci. USA 55, 712–716. Dunn M.S. and Fox S.W. (1933). The synthesis of aspartic acid. J. Biol. Chem. 101: 493–497 Edwards, P.M. (2002). Origin 7.0: scientific graphing and data analysis software. J. Chem. Inf. Comput. Sci. 42, 1270–1271. Eliot, A.C., and Kirsch, J.F. (2004). Pyridoxal phosphate enzymes: mechanistic, structural, and evolutionary considerations. Annu. Rev. Biochem. 73, 383–415. Fernandez FJ, Vega MC, Lehmann F, Sandmeier E, Gehring H, Christen P, Wilmanns M. (2004) Structural studies of the catalytic reaction pathway of a hyperthermophilic histidinol-phosphate aminotransferase. J Biol Chem. 279, 21478-21488 Ferreira GC, Gong J. (1995) 5-Aminolevulinate synthase and the first step of heme biosynthesis. J. Bioenerg. Biomembr. 27, 151–59. Finkelstein JD, Kyle WE, Martin JJ, Pick AM. (1975) Activation of cystathionine synthase 64 by adenosylmethionine and adenosylethionine. Biophys. Biochem. Res. Commun. 66, 81–87 Gallagher DT, Gilliland GL, Xiao G, Zondlo J, Fisher KE, Chinchilla D, Eisenstein E. (1998) Structure and control of pyridoxal phosphate dependent allosteric threonine deaminase. Structure 6:465–75. Graber,R.,Kasper,P.,Malashkevich, V.N.,Strop, P.,Gehring, H., Jansonius, J.N., and Christen, P. (1999). Conversion of aspartate aminotransferase into an L-aspartate beta-decarboxylase by a triple active-site mutation. J. Biol. Chem. 274, 31203–31208. Grant, R.A., Filman, D.J., Finkel, S.E., Kolter, R., and Hogle, J.M. (1998). The crystal structure of Dps, a ferritin homolog that binds and protects DNA. Nat. Struct. Biol. 5, 294–303. Hennig M, Grimm B, Contestabile R, John RA, Jansonius JN. (1997) Crystal structure of glutamate-1-semialdehyde aminomutase: an alpha2-dimeric vitamin B6-dependent enzyme with asymmetry in structure and active site reactivity. Proc. Natl. Acad. Sci. USA 94, 4866–71. Holm, L., and Sander, C. (1996). Mapping the protein universe. Science 273, 595–603. Hutson S. (2001) Structure and function of branched chain aminotransferases. Prog. Nucleic Acid Res. Mol. Biol. 70, 175–206. Jansonius, J.N. (1998). Structure, evolution and action of vitamin B6-dependent enzymes. Curr. Opin. Struct. Biol. 8, 759–769. Jones, T.A., Zou, J.Y., Cowan, S.W., and Kjeldgaard, M. (1991). Improved methods for building protein models in electron density maps and the location of errors in these models. Acta Crystallogr. A 47, 110–119. 65 Keller J.W., Baurick K.B., Rutt G.C., O'Malley M.V., Sonafrank N.L., Reynolds R.A., Ebbesson L.O., Vajdos F.F. (1990) Pseudomonas cepacia 2,2-dialkylglycine decarboxylase. Sequence and expression in Escherichia coli of structural and repressor genes. J. Biol. Chem. 265, 5531-5539. Kern A.D., Oliveira M.A., Coffino P., Hackert M.L. (1999) Structure of mammalian ornithine decarboxylase at 1.6 Å resolution: stereochemical implications of PLPdependent amino acid decarboxylases. Structure. 7, 567–81 Kochhar S, Christen P. (1992) Mechanism of racemization of amino acids by aspartate aminotransferase. Eur. J. Biochem. 203, 563–69. Kravchuk Z., Tsybovsky Y., Koivulehto M., Vlasov A., Chumanevich A., Battchikova N., Martsev S., and Korpela T., (2001). Truncated aspartate aminotransferase from alkalophilic Bacillus circulans with deletion of N-terminal 32 amino acids is a non-functional monomer in a partially structured state. Protein Engineering. 14, 279-285. Kraulis, P.J. (1991). MOLSCRIPT: a program to produce both detailed and schematic plots of protein structure. J. Appl. Cryst. 24, 946–950. Kraus J.P., Janosik M, Kozich V, Mandell R, Shih V, Sperandeo M.P., Sebastio G, de Franchis R, Andria G, Kluijtmans L.A., Blom H, Boers G.H., Gordon R.B., Kamoun P.T. (1999) Cystathionine beta-synthase mutations in homocystinuria. Hum. Mutat. 13, 362–375. Krupka, H.I., Huber, R., Holt, S.C., and Clausen, T. (2000). Crystal structure of cystalysin from Treponema denticola: a pyridoxal 50-phosphate-dependent protein acting as a haemolytic enzyme. EMBO J. 19, 3168–3178. Laskowski, R.A., MacArthur, M.W., Moss, D.S., and Thornton, J.M. (1993). PROCHECK: a program to check the stereochemical quality of protein structures. J. Appl. Cryst. 26, 66 283–291. Lee B.I.,and Suh S.W.(2004) Crystal Structure of the Schiff Base Intermediate Prior to Decarboxylation in the Catalytic Cycle of Aspartate alpha-Decarboxylase.J Mol Biol. 2004 Jun 25;340 (1):1-7. Lee, H.S., Kim, M.S., Cho, H.S., Kim, J.I., Kim, T.J., Choi, J.H., Park, C., Lee, H.S., Oh, B.H., and Park, K.H. (2002). Cyclomaltodextrinase, neopullulanase, and maltogenic amylase are nearly indistinguishable from each other. J. Biol. Chem. 277, 21891–21897. Liang F. and Kirsch J.F.(2000) L-Vinylglycine Is an Alternative Substrate as Well as a Mechanism-Based Inhibitor of 1-Aminocyclopropane-1-carboxylate Synthase Biochemistry, 39 (10), 2436–2444. Lima, S., Sundararaju, B., Huang, C., Khristoforov R., Momany C., and Phillips R.S., The crystal structure of the Pseudomonas dacunhae aspartate-β-decarboxylase dodecamer reveals an unknown oligomeric assembly for a pyridoxal-5′- phosphate- dependent enzyme J. Mol. Biol. (2009) 388, 98–108. Madison JT, Thompson JF. (1976) Threonine synthetase from higher plants: stimulation by S-adenosylmethionine and inhibition by cysteine. Biophys. Biochem. Res. Commun. 71, 684–691. Matsui I., Matsui E., Sakai Y. Kikuchi H., Kawarabayasi Y., Ura H. Kawaguchi S.I., Kuramitsu S., and Harata K., (2000) The molecular structure of hyperthermostable aromatic aminotransferase with novel substrate specificity form Pyrococcus horikoshii. J. Biol. Chem. 275., 4871-4879. McKellar R.C. Paquet A. and Ma C.Y. (1992) Antimicrobial activity of fatty N-acylamino acids against Gram-positive foodborne pathogens. Food Microbiology, 9, 67-76. 67 McPhalen, C.A., Vincent, M.G., and Jansonius, J.N. (1992). X-ray structure refinement and comparison of three forms of mitochondrial aspartate aminotransferase. J. Mol. Biol. 225, 495–517. Meister, A., Sober, H.A., and Tice, S.V. (1951). Enzymatic decarboxylation of aspartic acid to alpha-alanine. J. Biol. Chem. 189, 577–590. Merritt, E.A., and Murphy, M.E.P. (1994). Raster3D version 2.0: a program for photorealistic molecular graphics. Acta Crystallogr. D. Biol. Crystallogr. 50, 869–873. Mehta P.K., Christen P. (2000) The molecular evolution of pyridoxal 5'-phosphatedependent enzymes. Adv. Enzymol.Relat. Areas Mol. Biol. 74, 129–184. Michael D.T., Erhard H. John W.K. Johan N.J. (1995) Structural and Mechanistic analysis of two refined crystal structures of the pyridoxal phosphate-dependent enzyme dialkylglycine decarboxylase. J. Mol. Bio. 245:151-179. Miles E.W. (2001) Tryptophan synthase : a multienzyme complex with an intramolecular tunnel. Chem. Rec. 1:140–151. Mudd S.H, Finkelstein J.D, Irreverre F, Laster L. (1964) Homocystinuria : an enzymatic defect. Science 143, 1443–45. Novogrodsky, A., Nishimura, J.S., and Meister, A. (1963). Transamination and betadecarboxylation of aspartate catalyzed by the same pyridoxal phosphate-enzyme. J. Biol. Chem. 238, 1903–1905. Otwinowski, Z., and Minor, W. (1997). Processing of x-ray diffraction data collected in oscillation mode. Methods Enzymol. 276, 307–326. Rao NA, Talwar R, Savithri HS. (2000) Molecular organization, catalytic mechanism and function of serine hydroxymethyltransferase - a potential target for cancer chemotherapy. 68 Int. J. Biochem. Cell Biol. 32, 405–416. Rathod P.K. and Fellman J.H. (1985) Regulation of mammalian aspartate 4- decarboxylase: Its possible role in oxaloacetate and energy metabolixm. Arch. Biochem. Biophy. 238, 447-451. Rhee S. Silva M.M. Hyde C.C. Rogers P.H. Metzler C.M. Metzler D.E. and Arnone A. (1997) Refinement and comparisons of the crystal structures of pig cytosolic aspartate aminotransferase and its complex with 2-methylaspartate. J. Biol. Chem. 272, 17293-17302. Rosenberg, R.M., and O’Leary, M.H. (1985). Aspartate beta-decarboxylase from Alcaligenes faecalis: carbon-13 kinetic isotope effect and deuterium exchange experiments. Biochemistry 24, 1598–1603. Rozzell, J.D. (1991). Method and compositions for the production of L-alanine and derivatives there of. US Patent No. 5019509. Russo, S., and Baumann, U. (2004). Crystal structure of a dodecameric tetrahedralshaped aminopeptidase. J. Biol. Chem. 279, 51275–51281. Schneider G, Kack H, Lindqvist Y. (2000) The manifold of vitamin B6 dependent enzymes. Structure. 8, R1–6. Schoehn, G.,Vellieux,F.M., Asuncio′nDura′ ,M.,Receveur-Bre′ chot,V., Fabry,C.M., Ruigrok, R.W., Ebel, C., Roussel, A., and Franzetti, B. (2006). An archaeal peptidase assembles into two different quaternary structures: A tetrahedron and a giant octahedron. J. Biol. Chem. 281, 36327–36337. Soda, K., Novogrodsky, A., and Meister, A. (1964). Enzymatic desulfination of cysteine sulfinic acid. Biochemistry 3, 1450–1454. 69 Sugio S, Petsko GA, Manning JM, Soda K, Ringe D. (1995) Crystal structure of a D-amino acid aminotransferase : how the protein controls stereoselectivity. Biochemistry 34, 9661–9669. Tai CH, Cook PF. (2001) Pyridoxal 5'-phosphate-dependent alpha, beta-elimination reactions: mechanism of O-acetylserine sulfhydrylase. Acc. Chem. Res. 34, 49–59. Tate, S.S., and Meister, A. (1969). Regulation of the activity of L-aspartate beta decarboxylase by a novel allosteric mechanism. Biochemistry 8, 1660–1668. Tate, S.S., and Meister, A. (1970). Regulation and subunit structure of aspartate beta-decarboxylase. Studies on the enzymes from Alcaligenes faecalis and Pseudomonas dacunhae. Biochemistry 9, 2626–2632. Tate, S.S., and Meister, A. (1971). L-aspartate-beta-decarboxylase: structure, catalytic activities, and allosteric regulation. Adv. Enzymol. Relat. Areas Mol. Biol. 35, 503–543. Terwilliger, T.C. (2000). Maximum likelihood density modification. Acta Crystallogr. D. Biol. Crystallogr. 56, 965–972. Terwilliger, T.C. (2002). Automated main-chain model-building by template matching and iterative fragment extension. Acta Crystallogr. D. Biol. Crystallogr. 59, 33–44. Terwilliger, T.C., and Berendzen, J. (1999). Automated MAD and MIR structure solution. Acta Crystallogr. D. Biol. Crystallogr. 55, 849–861. Toney, M.D., and Krisch, J.F. (1993). Lysine 258 in aspartate aminotransferase : Enforcer of the Circe effect for amino acid substrates and the general-base catalyst for the 1,3-prototropic shift. Biochemistry 32, 1471–1479. Villeret, V., Tricot, C., Stalon, V., and Dideberg, O. (1995). Crystal structure of Pseudomonas aeruginosa catabolic ornithine transcarbamoylase at 3.0-A° resolution: a different 70 oligomeric organization in the transcarbamoylase family. Proc. Natl. Acad. Sci. USA 92, 10762–10766. Wada, M.; Nakamori, S.; Takagi, H. (2003) Serine racemase homologue of Saccharomyces cerevisiae has L-threo-3-hydroxyaspartate dehydratase activity FEMS Microbiol Lett 225 189-93. Wang, N.C., and Lee, C.Y. (2006). Molecular cloning of the aspartate 4-decarboxylase gene from Pseudomonas sp. ATCC 19121 and characterization of the bifunctional recombinant enzyme. Appl. Microbiol. Biotechnol. 73, 339–348. Wang, N.C., and Lee, C.Y. (2007). Enhanced transaminase activity of a bifunctional L-aspartate 4-decarboxylase. Biochem. Biophys. Res. Commun. 356, 368–373. Wang, N.C., Ko, T.P., and Lee, C.Y. (2008). Inactive S298R disassembles the dodecameric L-aspartate 4-decarboxylase into dimers. Biochem. Biophys. Res. Commun. 374, 134–137. Wang, N.C. PHD thesis (2006). Characterization of L-aspartate 4-decarboxylase and investigation on its critical residues of bifunctional enzyme activity. National Taiwan University. Wilson, E.M., and Kornberg, H.L. (1963). Properties of crystalline L-aspartate 4-carboxylyase from Achromobacter sp. Biochem. J. 88, 578–587. Yernool D, Boudker O, Jin Y, Gouaux E (2004) Structure of a glutamate transporter homologue from Pyrococcus horikoshii. Nature, 431, 811-818. | |
| dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/44150 | - |
| dc.description.abstract | 本論文主要是探究Alcaligenes faecalis 菌株中L-天門冬胺酸β-去羧酶(L‐aspartate
β‐decarboxylase (ASD))之立體結構與酵素功能分析。此類酵素於1950 年起應用於工業酵素 製造、合成抗生素或食品添加劑中。AsdA 乃一雙功能酵素,屬於磷酸比哆醛第一型(PLP Fold Type I)酵素,其主要作用為「去羧基反應」-催化L‐aspartate 形成L‐alanine 及CO2 分子; 次為「轉胺反應」-以乒乓(ping‐pong)作用方式轉胺於oxaloacetate 上,形成L‐glutamate。 研究中應用重金屬汞(Hg)之繞射強度差異,以multiple anomalous dispersion(MAD)方式 解析出AsdA 蛋白結構之相位角(phase angle),並建構其組成胺基酸之原子空間位置。結果 指出AsdA 蛋白以雙分子為基本單位,可組裝成12 個分子之truncated tetrahedron 幾何結 構的巨分子;並具有四個活性中心:受質結合中心(βY‐loop‐βZ)、PLP 催化中心(Lys315)、結 構調節中心(α13‐α15)及分子聚合中心(α3‐α5及α16‐α17)。 而藉由沉降係數分析及pH 活性測試,發現具活性之AsdA 蛋白於生物體中以12 分子 組合結構存在。每單分子分為二個領域(domain)-大領域(L‐domain)及小領域(S‐domain), 其大小領域間存在一個磷酸比哆醛(PLP)輔脢分子。於磷酸比哆醛C2 上之甲基與胺基酸 Lys315 的N4 形成Schiff 鍵,其磷酸根與周圍胺基酸形成氫鍵網,並與α8 雙螺旋結構上的 P 型環(P‐loop)以偶極之(dipole)力量存在。AsdA 分子結構受到pH 值調控,當pH 小於7 時 致AsdA 六個雙分子相互緊密結合且活性增加,而pH 增加至8.5 時,使AsdA 解離成無活 性之雙分子。 實驗中從PLP結構相對位置設計七個胺基酸突變區(K17A、R37A、Y134F、Y207F、K315A、 Y441A 及R487A)並比較其活性,以探討酵素催化模式。結果發現Y134 提供氫氧基至相鄰 單體的PLP 催化中心,以氫鍵穩定相鄰單體內的PLP 輔脢分子,喪失此氫氧基團將降低60% 去羧基的反應效率。除R487A 外,六種突變蛋白平均皆降低30%的反應速率,其中K17A 及R37A 則提高50%的受質結合力,Y134F 及K315A 則降低40%的受質結合力,Y207F 及Y441F 仍維持60%的催化效率,不影響受質結合力。而Arg487 位於受質結合中心中央,失去正電 荷的側鍊基團(R487A)使AsdA 活性完全喪失,但不影響十二倍體蛋白立體結構的組裝。其 ii 每個原子的振動值明顯降低至基本線,表示分子間的移動或振動與原態AsdA 有極大的不 同,突顯出Arg487 位於重要的樞紐。 此外,AsdA 酵素活性亦受到pH 值調控,當pH 小於6 時,去羧基反應之活性大幅提 高50 倍以上。在中性環境下,K17A、R37A 及Y441F 的L‐aspartate 消耗率比原態AsdA 還 快,與其產物(L‐alanine)含量不成正比,預測L‐aspartate 的消耗原因乃捨去羧基反應且進行 轉胺反應。 本研究之AsdA 蛋白與Pseudomonase sp.菌株之相似度極高的L-天門冬胺酸β-去羧 酶(AsdP)具有相似之磷酸比哆醛第一型酵素具有受質引發構型改變(substrate induced conformational change)現象-晶體加入抑制劑(β‐chloroalanine)浸泡,會引發晶胞(unit cell) 大小改變,其AsdP 晶格相同,晶胞大小平均單軸增長2.7%,總體積變化高達10%。研究 亦發現此巨分子結構的小領域(S‐domain)構型,因β‐chloroalanine 進入PLP 催化中心,造成 N 端的胺基酸(1‐38)朝六角形中心(α4 helix bundle)內移,藉凡得瓦力(van der Waals force)引 發區域性胺基酸(α19、α20 及α21 helices)移動5 Å 距離並轉動約22.5 度。 本研究論文透過現代科技的x‐ray 繞射技術,並結合結構生物技術及蛋白物理化學分 析,成功解出完整之AsdA 及AsdP 結構,更進一步探討雙功能酵素作用機制。並預測多功 能巨分子在生物體中所扮演的角色,包括胺基酸代謝、細胞內重要胺基酸含量之調控及酵 素功能的轉換,如L‐glutamate 與glutamate decarboxylase 及其反向轉運體(antiporter)之角 色關係。透過AsdA 及AsdP 酵素的結構的進一步解析,將有助於酵素基礎研究之瞭解,更 能促進相關科學之發展。 | zh_TW |
| dc.description.abstract | The focus of this PhD thesis is the type-I PLP (pyridoxal 5’-phosphate) enzyme
L-aspartate β-decarboxylase (ASD, from Alcaligenes faecalis) with particular reference to an analysis of protein structure determination and functional activity characterization. The ASD has bi-functional activity. The major one being the conversion of aspartate to alanine and CO2 by decarboxylation, but additionally, it also functions to transaminate aspartate to produce oxaloacetate. Similar to the homodimeric aminotransferases, its protein subunit comprises a large and a small domain, of 410 and 120 residues, respectively. The crystal structure reveals a dodecamer made of six identical dimers which are arranged in a truncated tetrahedron whose assembly involves tetramer and hexamer as intermediates. Based on this structure, we proposed a catalysis mechanism and four functional motifs: a substrate binding motif (βY-loop-βZ), a PLP binding site (Lys315), a regulatory motif (α1- α2 and α13- α15) and an assembly motif (α3- α5 and α16- α17). The additional helical motifs I (α3- α5) and II (α16- α17) participate in the oligomer formation. Triple mutations of S67R/Y68R/M69R or S67E/Y68E/M69E in motif I produced an inactive dimer. The functional dodecamer structure is rather distinct from the aminotransferase family. The PLP is bound covalently to Lys315 in the active site, while its phosphate group interacts with the neighboring Tyr134. Removal of the bulky side chain of Arg37, which overhangs the PLP group, improved the substrate affinity. Mutations in flexible regions produced the more active K17A and the completely inactive R487A. The structure also suggests that substrate binding triggers conformational changes essential for catalyzing the reaction. The substrate induced S-domain conformational change was elucidated by β-chloralanine–AsdP complex. Along the three-fold axis of ASD structure, there are four 1.4 Å radius in size pores were appeared iv on each three α4 helices bundle of the plate shape hexamer. The surface electron potential of α4-α5 helices was changed from most positive charge to half hydrophobicity that cooperated with N-terminal moved and rotated about 5 Å and 22.5 degree, respectively. The cross-interaction of S-domain involved with van der Waals force between α1 to α2, α1 to α20, and α20 to α21 helices those move together by hydrophobic patch I, II, and III. The Arg497 residue has observed that was contributed with stabilize carboxyl group of side chain of β-chloralanine-PLP complex as ATase’s enzymatic reaction. | en |
| dc.description.provenance | Made available in DSpace on 2021-06-15T02:42:12Z (GMT). No. of bitstreams: 1 ntu-98-D89242003-1.pdf: 6760448 bytes, checksum: 425cc2c63dd46aebd75d90fe8933692c (MD5) Previous issue date: 2009 | en |
| dc.description.tableofcontents | 中文摘要 ........................................................................................................................................ i
Abstract .......................................................................................................................................... iii Abbreviations ................................................................................................................................. v Chapter 1 Introduction ................................................................................................................... 1 The story of L-aspartate β-decarboxylase ............................................................................. 4 Amino acid metabolism of ASD ............................................................................................... 5 Biochemical characterization of ASD ...................................................................................... 7 Chapter 2 Materials and Methods ............................................................................................. 10 Single and multiple point mutations ...................................................................................... 10 Protein expression and purification ....................................................................................... 10 Circular dichroism ( CD ) spectroscopy analysis ................................................................ 11 Molecular weight determination by analytical ultracentrifugation ( AUC ) ....................... 12 Determination of the binding number by isothermal calorimeter ( ITC ) ......................... 13 Protein particle size determination by dynamic light scattering ( DLS ) .......................... 13 UV-visible spectrophotometry ................................................................................................ 14 Determination of the conformational change by Fluorescence meter ............................. 14 Determination of the enzyme kinetics by HPLC .................................................................. 15 Crystal screening for L-aspartate β-decarboxylase (ASD)………………………………16 Crystallization conditions, data collection, structure determination and refinement ...... 17 Crystallization conditions .............................................................................................. 17 Data collection ................................................................................................................ 17 Phase strategy and MAD determination .................................................................... 19 Model building ................................................................................................................ 20 Molecular replacement (MR) ........................................................................................ 21 Multiple isomorphism replacement (MIR) .................................................................. 23 Structure refinement ...................................................................................................... 23 PDB accession codes ................................................................................................... 24 Chapter 3 Results ........................................................................................................................ 25 Improvement of X-ray diffraction on AsdA from salt to protein crystal condition ........... 25 Two-step purification for ASD protein ......................................................................... 25 Protein concentration .................................................................................................... 26 Buffer effect ..................................................................................................................... 26 Anti-freeze reagent ........................................................................................................ 27 The native reflection data of both ASD ................................................................................. 28 Solving the ASD structure ....................................................................................................... 29 Using the molecular replacement method ................................................................. 29 Using the isomorphism displacement method .......................................................... 30 Solving the Phase problem by two wavelength MAD method ................................ 31 ASD structure determination is complicated by two methods .......................................... 32 A truncated tetrahedron geometry of the macromolecule ASD ........................................ 33 The dimer as a basic unit of dodecamer structure ............................................................. 33 The monomer structure comparison ..................................................................................... 34 A similar PLP binding site to the AT family ........................................................................... 36 The dodecamer structure assembly depends on pH value............................................... 37 The important interface structure .......................................................................................... 38 Lost decarboxylase activity on dimer structure ................................................................... 40 The role of PLP surrounding residuals and their activity ................................................... 42 Substrate induced conformational change and mechanism prediction .......................... 45 Chapter 4 Discussion .................................................................................................................. 50 Structure determination ........................................................................................................... 50 Dodecamer enzyme activity ................................................................................................... 51 Similar folding with different activity and In vivo function .................................................. 53 The bi-functionality of ASD in relation to the substrate interaction face .......................... 55 Two base mechanism ............................................................................................................. 58 Specialized dodecamer structure .......................................................................................... 59 Reference ………………………………………………………………………………….……61 Schemes ....................................................................................................................................... 71 Scheme 1. The PLP-dependent enzyme catalysis position and torsion angle of internal aldimine ................................................................................................................... 72 Scheme 2. The major stratagem of determining ASD protein structure ............................ 73 Scheme 3. The proposed mode of dodecamer activity. ....................................................... 74 Figures .......................................................................................................................................... 75 Figure 1. The ASD protein expression, purification and crystallization ............................. 76 Figure 2. The heavy atom site of Hg derivative AsdP structure.......................................... 77 Figure 3. The buffer effect of oligomer population were elucidated by AUC .................... 78 Figure 4. The anomalous scattering factor ............................................................................ 79 Figure 5. The quaternary structure of the dodecamer ......................................................... 80 Figure 6. Structure alignment of the monomer of AsdA ....................................................... 81 Figure 7. The amino acid alignment of PLP enzymes ......................................................... 82 Figure 8. The monomer and dimer structures of ASD ......................................................... 83 Figure 9. The topology diagram of an AsdA monomer ......................................................... 84 Figure 10. The PLP binding site of ASD and AT ................................................................... 85 Figure 11. The active site structure ......................................................................................... 86 Figure 12 The environment of the active site ........................................................................ 87 Figure 13. The interface of dimer ............................................................................................ 88 Figure 14. The pH dependence of the dodecamer assembly of AsdA .............................. 89 Figure 15 The proposed assembly mechanism of AsdA ..................................................... 90 Figure 16. The α3-α 5 helices assembly motif ...................................................................... 91 Figure 17 The pH effect of the three α4 helices bundle and α3-loop-α4 .......................... 92 Figure 18. The circular dichroism (CD) spectra .................................................................... 93 Figure 19. The UV/Vis spectra of ASD ................................................................................... 94 Figure 20. The UV spectra of aldimine PLP reduced by L-aspartate treatment .............. 95 Figure 21. The B value and RMSD analysis ......................................................................... 96 Figure 22. The sigmoid kinetic of ASD ................................................................................... 97 Figure 23 The substrate binding number by ITC determination ......................................... 98 Figure 24 The comparison of substrate binding site with AT complex .............................. 99 Figure 25. The flexible N-terminal segment and βY-loop-βz random coil ....................... 100 Figure 26. The proposed a catalytic mechanism of AsdA ................................................. 101 Figure 27. The structure of β−chloralanine-AsdP complex ............................................... 102 Figure 28. The substrate induced S-domain conformational change of ASD complex 103 Figure 29. The contribution of hydrophobic patch cross-interaction occur in S-domain104 Figure 30. The ASD metabolism is depend on pH ............................................................. 105 Tables .......................................................................................................................................... 106 Table I. The common name of L-Aspartate β−decarboxylase .......................................... 107 Table II. The ASD protein has been found on different species ....................................... 108 Table III. Data collection and refinement statistics of the ASD crystals........................... 109 Table IV. Models of AT and DC as a search model for MR method ................................. 110 Table V. The list of heavy atom soaking with AsdA crystals .............................................. 111 Table VI. The slow transformation of unit cell diameter of ASD is depend on soaking time .……………………………………………………………………………… 112 Table VII. The variant of the three axes distance of AsdA and its mutants ..................... 113 Table VIII. the list of RMSD comparison of each chains of asymmetry unit ................... 114 Table IX. Effects of mutations on the kinetic parameters of AsdA .................................... 115 Table X. Residues at the interface between two dimers in an AsdA dodecamer ........ 116 Appendix ..................................................................................................................................... 117 Appendix A. The Effects of mutation on activity and assembly of AsdP ......................... 118 Appendix B. The detail dissection from monomer to dodecamer of AsdA ...................... 119 Appendix C. The optimal pH and temperature of AsdA .................................................... 120 Appendix D. The enzyme kinetics performed on pH 7.4 condition ................................. 121 Appendix E. The assembly and cofactor list of other decarboxylase ............................. 122 Appendix F. The tetrahedron assembly dodecamer structure proteins .......................... 123 Appendix G. The membrane associated character of AsdA ............................................ 124 Appendix H. The TEM of AsdA in different pH ................................................................... 125 Appendix I. The confocal image of anti-His Ab labeled AsdA of E.coli ........................... 126 Appendix J. The proposed inhibitor – AsdA complex ........................................................ 127 | |
| dc.language.iso | en | |
| dc.subject | 十二倍體組裝 | zh_TW |
| dc.subject | beta-去羧酶 | zh_TW |
| dc.subject | 轉胺酶 | zh_TW |
| dc.subject | 雙功能酵素 | zh_TW |
| dc.subject | 酸鹼依順性 | zh_TW |
| dc.subject | 磷酸比哆醛 | zh_TW |
| dc.subject | X-ray繞射 | zh_TW |
| dc.subject | X-ray diffraction | en |
| dc.subject | pyridoxal 5’-phosphate | en |
| dc.subject | dodecamer assembly | en |
| dc.subject | aminotransferase | en |
| dc.subject | pH dependent | en |
| dc.subject | beta-decarboxylase | en |
| dc.subject | bi-functional enzyme | en |
| dc.title | L-天門冬胺酸β-去羧酶十二倍體蛋白之立體功能結構鑑定及磷酸比哆醛依順機制 | zh_TW |
| dc.title | Structure, Assembly, and Mechanism of a PLP-dependent Dodecameric L-Aspartate β-Decarboxylase | en |
| dc.type | Thesis | |
| dc.date.schoolyear | 97-2 | |
| dc.description.degree | 博士 | |
| dc.contributor.oralexamcommittee | 李佳音(Chia-Yin Lee),袁小琀(Hanna S. Yuan),馬徹(Che Alex Ma),陳光超(Guang-Chao Chen) | |
| dc.subject.keyword | beta-去羧酶,轉胺酶,雙功能酵素,酸鹼依順性,磷酸比哆醛,X-ray繞射,十二倍體組裝, | zh_TW |
| dc.subject.keyword | beta-decarboxylase,aminotransferase,pyridoxal 5’-phosphate,pH dependent,bi-functional enzyme,X-ray diffraction,dodecamer assembly, | en |
| dc.relation.page | 127 | |
| dc.rights.note | 有償授權 | |
| dc.date.accepted | 2009-08-11 | |
| dc.contributor.author-college | 生命科學院 | zh_TW |
| dc.contributor.author-dept | 生化科學研究所 | zh_TW |
| 顯示於系所單位: | 生化科學研究所 | |
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