1
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Schowen KB, Schowen RL, Borchardt SE, Borchardt PM, Artursson P, Audus KL, Augustijns P, Nicolazzo JA, Raub TJ, Schöneich C, Siahaan TJ, Takakura Y, Thakker DR, Wolfe MS. A Tribute to Ronald T. Borchardt—Teacher, Mentor, Scientist, Colleague, Leader, Friend, and Family Man. J Pharm Sci 2016; 105:370-385. [DOI: 10.1002/jps.24687] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 09/24/2015] [Indexed: 11/08/2022]
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2
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Cai S, Li QS, Fang J, Borchardt RT, Kuczera K, Middaugh CR, Schowen RL. The rationale for targeting the NAD/NADH cofactor binding site of parasitic S-adenosyl-L-homocysteine hydrolase for the design of anti-parasitic drugs. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2010; 28:485-503. [PMID: 20183598 DOI: 10.1080/15257770903051031] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Trypanosomal S-adenoyl-L-homocysteine hydrolase (Tc-SAHH), considered as a target for treatment of Chagas disease, has the same catalytic mechanism as human SAHH (Hs-SAHH) and both enzymes have very similar x-ray structures. Efforts toward the design of selective inhibitors against Tc-SAHH targeting the substrate binding site have not to date shown any significant promise. Systematic kinetic and thermodynamic studies on association and dissociation of cofactor NAD/H for Tc-SAHH and Hs-SAHH provide a rationale for the design of anti-parasitic drugs directed toward cofactor-binding sites. Analogues of NAD and their reduced forms show significant selective inactivation of Tc-SAHH, confirming that this design approach is rational.
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Affiliation(s)
- Sumin Cai
- Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas, USA
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3
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Wnuk SF, Sacasa PR, Restrepo J. Application of germyldesulfonylation reactions to the synthesis of germanium-containing nucleoside analogues. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2010; 28:537-49. [PMID: 20183601 DOI: 10.1080/15257770903054340] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Treatment of the protected (E)-5'-deoxy-5'-[(p-toluenesulfonyl)methylene]uridine and adenosine derivatives with tributyl- or triphenylgermane hydride (AIBN/toluene/Delta) effected radical-mediated germyldesulfonylations to give 5'-(tributyl- or triphenylgermyl)methylene-5'-deoxyuridine and adenosine derivatives as single (E)-isomers. Analogous treatment of 2'-deoxy-2'-[(phenylsulfonyl)methylene]uridine with Ph(3)GeH afforded the corresponding vinyl triphenylgermane product. Stereoselective halodegermylation of the (E)-5'-(tributylgermyl)methylene-5'-deoxy nucleosides with N-iodosuccinimide or N-bromosuccinimide provided the Wittig-type (E)-5'-deoxy-5'-(halomethylene) nucleosides quantitatively, while no halodegermylations was observed with the 5'-deoxy-5'-(triphenylgermyl)methylene counterparts. Treatment of the vinyl trialkylgermanes with aqueous trifluoroacetic acid effected protiodegermylation, while vinyl triarylgermanes were stable under the acidic conditions.
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Affiliation(s)
- Stanislaw F Wnuk
- Department of Chemistry & Biochemistry, Florida International University, Miami, Florida, USA.
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4
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Wnuk SF, Sacasa PR, Lewandowska E, Andrei D, Cai S, Borchardt RT. Synthesis of 5'-functionalized nucleosides: S-Adenosylhomocysteine analogues with the carbon-5' and sulfur atoms replaced by a vinyl or halovinyl unit. Bioorg Med Chem 2008; 16:5424-33. [PMID: 18457953 PMCID: PMC2443866 DOI: 10.1016/j.bmc.2008.04.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2007] [Revised: 04/05/2008] [Accepted: 04/09/2008] [Indexed: 11/17/2022]
Abstract
Adenosine and uridine analogues functionalized with alkenyl or fluoroalkenyl chain at C5' were prepared employing cross-metathesis, Negishi couplings, and Wittig reactions. Metathesis of the protected 5'-deoxy-5'-methyleneadenosine or uridine analogues with six-carbon amino acids (homoallylglycines) in the presence of Grubbs catalysts gave nucleoside analogues with the C5'-C6' double bond. Alternatively, the Pd-catalyzed cross-coupling between the protected 5'-deoxy-5'-(iodomethylene) nucleosides and suitable alkylzinc bromides also provided analogues with alkenyl unit. Stereoselective Pd-catalyzed monoalkylation of 5'-(bromofluoromethylene)-5'-deoxyadenosine with alkylzinc bromides afforded adenosylhomocysteine analogues with a 6'-(fluoro)vinyl motif. The vinylic adenine nucleosides produced time-dependent inactivation of the S-adenosyl-l-homocysteine hydrolases.
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Affiliation(s)
- Stanislaw F Wnuk
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA.
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5
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Wang JF, Yang XD, Zhang LR, Yang ZJ, Zhang LH. Synthesis and biological activities of 5′-ethylenic and acetylenic modified l-nucleosides and isonucleosides. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.06.131] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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6
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Steere JA, Honek JF. Synthesis and biological activity of novel S-adenosyl-L-homocysteine hydrolase inhibitors. Bioorg Med Chem 2003; 11:3229-36. [PMID: 12837532 DOI: 10.1016/s0968-0896(03)00301-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Four potential S-adenosyl-L-homocysteine hydrolase inhibitors were prepared and tested against purified recombinant rat liver enzyme. Preliminary studies indicate that three of these compounds, 1, 2, and 4, caused time-dependent inactivation of S-adenosyl-L-homocysteine hydrolase but showed a biphasic nature. Compound 3 was found to be a rapid equilibrium inhibitor of this enzyme.
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Affiliation(s)
- Jennifer A Steere
- Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
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7
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Guillerm G, Guillerm D, Vandenplas-Vitkowski C, Glapski C, De Clercq E. Inactivation of S-adenosyl-L-homocysteine hydrolase with novel 5'-thioadenosine derivatives. Antiviral effects. Bioorg Med Chem Lett 2003; 13:1649-52. [PMID: 12729633 DOI: 10.1016/s0960-894x(03)00279-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Synthesis of 5'-S-vinyl-5'-thioadenosine 5, 5'-S-ethynyl-5'-thioadenosine 7 and 5'-S-cyano-5'-thioadenosine 9 is described. Incubation of AdoHcy hydrolase with 5, 7 and 9 resulted in time- and concentration-dependent inactivation of the enzyme and partial depletion of its NAD(+) content. From these results and characterisation of metabolites released during the inactivation process, hypothetical mechanisms are suggested. The antiviral activity of 5, 7 and 9 was examined. Significant activities were noted with 5 against Vaccinia, Junin and Taccaribe viruses.
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Affiliation(s)
- Georges Guillerm
- Laboratoire de Chimie Bioorganique, UMR 6519, UFR Sciences, B.P. 1039, 51687 Reims cedex 2, France.
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8
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Steere JA, Sampson PB, Honek JF. Synthesis of an alpha-aminophosphonate nucleoside as an inhibitor of S-adenosyl-L-homocysteine hydrolase. Bioorg Med Chem Lett 2002; 12:457-60. [PMID: 11814819 DOI: 10.1016/s0960-894x(01)00789-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A phosphonic acid analogue of S-adenosyl-L-homocysteine was prepared by a novel method and the epimeric mixture separated. Preliminary studies indicate that each epimer causes time-dependent inactivation of S-adenosyl-L-homocysteine hydrolase, however each presented distinct kinetic characteristics.
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Affiliation(s)
- Jennifer A Steere
- Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
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9
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Kitade Y, Nakanishi M, Yatome C. 9-[(2'S,3'S)-3'-formyl-2',3'-dihydroxypropyl]adenine: a facile affinity-labeling probe of human S-adenosyl-L-homocysteine hydrolase. Bioorg Med Chem Lett 1999; 9:2737-40. [PMID: 10509926 DOI: 10.1016/s0960-894x(99)00470-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Treatment of human recombinant S-adenosyl-L-homocysteine (SAH) hydrolase with 9-[(2'S,3'S)-3'-formyl-2',3'-dihydroxypropyl]adenine (FDHPA) caused irreversible inactivation in a time- and concentration-dependent manner (Ki = 8.8 microM, k(inact) = 0.09 min(-1)). FDHPA behaved as a facile affinity-labeling probe of SAH hydrolase.
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Affiliation(s)
- Y Kitade
- Department of Biomolecular Science, Faculty of Engineering, Gifu University, Japan
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10
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Wnuk SF, Yuan CS, Borchardt RT, Morris JR. Design and Biological Evaluation of New Mechanismbased Inhibitors ofS-Adenosyl-L-homocysteine Hydrolase. ACTA ACUST UNITED AC 1999. [DOI: 10.1080/15257779908041506] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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11
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Yuan CS, Wnuk SF, Robins MJ, Borchardt RT. A novel mechanism-based inhibitor (6'-bromo-5', 6'-didehydro-6'-deoxy-6'-fluorohomoadenosine) that covalently modifies human placental S-adenosylhomocysteine hydrolase. J Biol Chem 1998; 273:18191-7. [PMID: 9660780 DOI: 10.1074/jbc.273.29.18191] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Most inhibitors of S-adenosylhomocysteine (AdoHcy) hydrolase function as substrates for the "3'-oxidative activity" of the enzyme and convert the enzyme from its active form (NAD+) to its inactive form (NADH) (Liu, S., Wolfe, M. S., and Borchardt, R. T. (1992) Antivir. Res. 19, 247-265). In this study, we describe the effects of a mechanism-based inhibitor, 6'-bromo-5', 6'-didehydro-6'-deoxy-6'-fluorohomoadenosine (BDDFHA), which functions as a substrate for the "6'-hydrolytic activity" of the enzyme with subsequent formation of a covalent linkage with the enzyme. Incubation of human placental AdoHcy hydrolase with BDDFHA results in a maximum inactivation of 83% with the remaining enzyme activity exhibiting one-third of the kcat value of the native enzyme. This partial inactivation is concomitant with the release of both Br- and F- ions and the formation of adenine (Ade). The enzyme can be covalently labeled with [8-3H]BDDFHA, resulting in a stoichiometry of 2 mol of BDDFHA/mol of the tetrameric enzyme. The 3H-labeled enzyme retains its original NAD+/NADH content. Tryptic digestion and subsequent protein sequencing of the [8-3H]BDDFHA-labeled enzyme revealed that Arg196 is the residue that is associated with the radiolabeled inhibitor. The partition ratio of the Ade formation (nonlethal event) to covalent acylation (lethal event) is approximately 1:1. From these experimental results, a possible mechanism by which BDDFHA inactivates AdoHcy hdyrolase is proposed: enzyme-mediated water addition at the C-6' position of BDDFHA followed by elimination of Br- ion results in the formation of homoAdo 6'-carboxyl fluoride (HACF). HACF then partitions in two ways: (a) attack by a proximal nucleophile (Arg196) to form an amide bond after expulsion of F- ion (lethal event) or (b) depurination to form Ade and hexose-derived 6-carboxyl fluoride (HDCF), which is further hydrolyzed to hexose-derived 6-carboxylic acid (HDCA) and F- ion (nonlethal event).
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Affiliation(s)
- C S Yuan
- Department of Biochemistry, The University of Kansas, Lawrence, Kansas 66047, USA
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12
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Turner MA, Yuan CS, Borchardt RT, Hershfield MS, Smith GD, Howell PL. Structure determination of selenomethionyl S-adenosylhomocysteine hydrolase using data at a single wavelength. NATURE STRUCTURAL BIOLOGY 1998; 5:369-76. [PMID: 9586999 DOI: 10.1038/nsb0598-369] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
S-Adenosylhomocysteine (AdoHcy) hydrolase regulates all adenosylmethionine-(AdoMet) dependent transmethylations by hydrolyzing the potent feedback inhibitor AdoHcy to homocysteine and adenosine. The crystallographic structure determination of a selenomethionyl-incorporated AdoHcy hydrolase inhibitor complex was accomplished using single wavelength anomalous diffraction data and the direct methods program, Snb v2.0, which produced the positions of all 30 crystallographically distinct selenium atoms. The mode of enzyme-cofactor binding is unique, requiring interactions from two protein monomers. An unusual dual role for a catalytic water molecule in the active site is revealed in the complex with the adenosine analog 2'-hydroxy, 3'-ketocyclopent-4'-enyladenine.
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Affiliation(s)
- M A Turner
- Structural Biology and Biochemistry, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
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13
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Yuan CS, Ault-Riché DB, Borchardt RT. Chemical modification and site-directed mutagenesis of cysteine residues in human placental S-adenosylhomocysteine hydrolase. J Biol Chem 1996; 271:28009-16. [PMID: 8910410 DOI: 10.1074/jbc.271.45.28009] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Human placental S-adenosylhomocysteine (AdoHcy) hydrolase (EC 3.3.1. 1) was inactivated by 5',5-dithiobis(2-nitrobenzoic acid) following pseudo-first-order kinetics. Modification of three of the 10 cysteine residues per enzyme subunit resulted in complete inactivation of the enzyme. The three modified cysteine residues were identified as Cys113, Cys195, and Cys421, respectively, by protein sequencing after modification with [1-14C]iodoacetamide. Of the three modifiable cysteines, Cys113 and Cys195 could be protected from modification in the presence of the substrate adenosine (Ado), which also protected the enzyme from inactivation. On the other hand, Cys421 was not protected by Ado, and modification of Cys421 alone did not affect the enzyme activity. To verify whether some of these cysteine residues are important for the enzyme catalysis, these three cysteine residues were replaced by either serine or aspartic acid using site-directed mutagenesis. Mutants of both Cys113 (C113S and C113D) and Cys421 (C421S and C421D) had enzyme activities similar to that of the wild-type enzyme, and only slight changes were observed in the steady-state kinetics measured in both the synthetic and hydrolytic directions. However, mutants of Cys195 (C195D and C195S) displayed drastically reduced enzyme activities, and kcat values were only 7 and 12% of that of the wild-type enzyme, respectively, resulting in a calculated loss in binding energy (DeltaDeltaG) of approximate 1 Kcal/mol. The Cys195 mutants were capable of catalyzing both the 3'-oxidative and 5'-hydrolytic reactions, as evidenced by the reduction of E.NAD+ to NADH and formation of the 5'-hydrolytic product when incubated with (E)-5', 6'-didehydro-6'-deoxy-6'-chlorohomoadenosine at rates comparable with those catalyzed by the wild-type enzyme. However, mutations of the Cys195 severely altered the 3'-reduction potential as evidenced by the drastic reduction in the rate of [2,8-3H]Ado release from the E-NADH.[2,8-3H]3'-keto-Ado complex. Circular dichroism studies of the Cys195 mutants confirmed that the observed effects are not due to changes in secondary structure. These results suggested that the Cys195 is involved in the catalytic center and may play an important role in maintaining the 3'-reduction potential for effective release of the reaction products and regeneration of the active form (NAD+ form) of the enzyme; the Cys113 is located in or near the substrate binding site, but plays no role beneficial to the catalysis; and the Cys421 is a nonessential residue, which also explains why Cys421 does not occur in any other known AdoHcy hydrolases.
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Affiliation(s)
- C S Yuan
- Department of Biochemistry, The University of Kansas, Lawrence, Kansas 66047, USA.
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14
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Yuan CS, Liu S, Wnuk SF, Robins MJ, Borchardt RT. Design and synthesis of S-adenosylhomocysteine hydrolase inhibitors as broad-spectrum antiviral agents. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s1075-8593(96)80103-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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15
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Yuan CS, Borchardt RT. Photoaffinity labeling of human placental S-adenosylhomocysteine hydrolase with [2-3H]8-azido-adenosine. J Biol Chem 1995; 270:16140-6. [PMID: 7608178 DOI: 10.1074/jbc.270.27.16140] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The potential photoaffinity probe 8-azido-adenosine (8-N3-Ado) was shown to serve as a substrate for the 3'-oxidative activity of human S-adenosylhomocysteine (AdoHcy) hydrolase (Aiyar, V. N., and Hershfield, M. S. (1985) Biochem. J. 232, 643-650). In this study, we have determined the equilibrium binding properties of 8-N3-Ado with AdoHcy hydrolase (NAD+ form) and identified the specific amino acid residues that are covalently modified. After irradiation of the reaction mixture of [2-3H]8-N3-Ado and AdoHcy hydrolase (NAD+ form) and followed by tryptic digestion, peptides specifically photolabeled by [2-3H]3'-keto-8-N3-Ado were effectively separated from peptides nonspecifically labeled with [2-3H]8-N3-Ado using boronate affinity chromatography. After purification by reverse phase high performance liquid chromatography, two photolabeled peptides were isolated and identified as Val175-Lys186 and Val319-Arg327, in which Ala177 and Ile321 were associated with radioactivity. The specificity of the photoaffinity labeling with [2-3H]3'-keto-8-N3-Ado was demonstrated by the observation that these photolabeled peptides were not isolated when [2-3H]8-N3-Ado was incubated with apo AdoHcy hydrolase and irradiated. The two photolabeled peptides are assumed to be parts of the adenine-binding domain for substrates. They are both within well conserved regions of AdoHcy hydrolases. The peptide Val175-Lys186 is located very close to Cys195 and Glu197. Ser198, both of which were indicated to be located in the active site of the enzyme by chemical modification and limited proteolysis methods. The peptide Val319-Arg327 is adjacent to Leu330, which is proposed by a computer graphics model to interact with the C-6-NH2 group of Ado.
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Affiliation(s)
- C S Yuan
- Department of Biochemistry, University of Kansas, Lawrence 66045, USA
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16
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A single mutation at lysine 426 of human placental S-adenosylhomocysteine hydrolase inactivates the enzyme. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)31718-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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