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Hilario E, Fan L, Mueller LJ, Dunn MF. PCR Mutagenesis, Cloning, Expression, Fast Protein Purification Protocols and Crystallization of the Wild Type and Mutant Forms of Tryptophan Synthase. J Vis Exp 2020. [PMID: 33044464 DOI: 10.3791/61839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Structural studies with tryptophan synthase (TS) bienzyme complex (α2β2 TS) from Salmonella typhimurium have been performed to better understand its catalytic mechanism, allosteric behavior, and details of the enzymatic transformation of substrate to product in PLP-dependent enzymes. In this work, a novel expression system to produce the isolated α- and isolated β-subunit allowed the purification of high amounts of pure subunits and α2β2 StTS complex from the isolated subunits within 2 days. Purification was carried out by affinity chromatography followed by cleavage of the affinity tag, ammonium sulfate precipitation, and size exclusion chromatography (SEC). To better understand the role of key residues at the enzyme β-site, site-direct mutagenesis was performed in prior structural studies. Another protocol was created to purify the wild type and mutant α2β2 StTS complexes. A simple, fast and efficient protocol using ammonium sulfate fractionation and SEC allowed purification of α2β2 StTS complex in a single day. Both purification protocols described in this work have considerable advantages when compared with previous protocols to purify the same complex using PEG 8000 and spermine to crystalize the α2β2 StTS complex along the purification protocol. Crystallization of wild type and some mutant forms occurs under slightly different conditions, impairing the purification of some mutants using PEG 8000 and spermine. To prepare crystals suitable for x-ray crystallographic studies several efforts were made to optimize crystallization, crystal quality and cryoprotection. The methods presented here should be generally applicable for purification of tryptophan synthase subunits and wild type and mutant α2β2 StTS complexes.
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Affiliation(s)
- Eduardo Hilario
- Department of Chemistry, University of California-Riverside;
| | - Li Fan
- Department of Biochemistry, University of California-Riverside
| | | | - Michael F Dunn
- Department of Biochemistry, University of California-Riverside
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2
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Modulation of FadR Binding Capacity for Acyl-CoA Fatty Acids Through Structure-Guided Mutagenesis. Protein J 2015; 34:359-66. [DOI: 10.1007/s10930-015-9630-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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3
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Miles EW. Tryptophan synthase: structure, function, and subunit interaction. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 49:127-86. [PMID: 400853 DOI: 10.1002/9780470122945.ch4] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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4
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Rondard P, Bedouelle H. A mutational approach shows similar mechanisms of recognition for the isolated and integrated versions of a protein epitope. J Biol Chem 1998; 273:34753-9. [PMID: 9856999 DOI: 10.1074/jbc.273.52.34753] [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: 11/06/2022] Open
Abstract
Antibody mAb164 is directed against the native form of the TrpB2 subunit of Escherichia coli tryptophan synthase. It recognizes a synthetic peptide, P11, constituted of residues 273-283 of TrpB, with high affinity. We introduced 16 single and 3 double mutations in each of the two contexts, TrpB2 and P11, and used them as local probes to study the cross-reactivity of mAb164 toward these two antigens. The equilibrium constant, KD, of dissociation from mAb164 was measured for each of the mutant derivatives of TrpB2 and P11 by a competition enzyme-linked immunosorbent assay and compared with the wild type one. The variation of the free energy of interaction, DeltaDeltaG, covered nearly 8 kcal/mol for the different mutations. The values of DeltaDeltaG for the mutant derivatives of TrpB2 and for those of P11 were close and the two sets of values were strongly correlated (r = 0.96). This correlation showed that mAb164 recognized the integrated and isolated versions of residues 273-283 with very similar mechanisms. A few significant differences between the recognitions of TrpB2 and P11 by mAb164 suggested some adaptability of the interaction. The results were compatible with a recognition of residues 273-283 of TrpB in a loop conformation, close to their structure in the crystals of the complete tryptophan synthase, TrpA2TrpB2.
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Affiliation(s)
- P Rondard
- Groupe d'Ingénierie des Protéines (CNRS URA 1129), Unité de Biochimie Cellulaire, Institut Pasteur, 28 rue du Docteur Roux, 75724 Paris Cedex 15, France
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5
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CRAWFORD IP, ITO J. SERINE DEAMINATION BY THE B PROTEIN OF ESCHERICHIA COLI TRYPTOPHAN SYNTHETASE. Proc Natl Acad Sci U S A 1996; 51:390-7. [PMID: 14171449 PMCID: PMC300083 DOI: 10.1073/pnas.51.3.390] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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6
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SCHWARTZ AK, BONNER DM. TRYPTOPHAN SYNTHETASE IN BACILLUS SUBTILIS: EFFECTS OF HIGH POTASSIUM ION CONCENTRATION ON A TWO COMPONENT ENZYME. ACTA ACUST UNITED AC 1996; 89:337-47. [PMID: 14203181 DOI: 10.1016/0926-6569(64)90223-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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NEWTON WA, SNELL EE. CATALYTIC PROPERTIES OF TRYPTOPHANASE, A MULTIFUNCTIONAL PYRIDOXAL PHOSPHATE ENZYME. Proc Natl Acad Sci U S A 1996; 51:382-9. [PMID: 14171448 PMCID: PMC300082 DOI: 10.1073/pnas.51.3.382] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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8
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Yee MC, Horn V, Yanofsky C. On the role of helix 0 of the tryptophan synthetase alpha chain of Escherichia coli. J Biol Chem 1996; 271:14754-63. [PMID: 8662916 DOI: 10.1074/jbc.271.25.14754] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The role of helix 0 of the alpha chain (TrpA) of the tryptophan synthetase alpha2beta2 multi-functional enzyme complex of Escherichia coli was examined by deleting amino-terminal residues 2-6, 2-11, or 2-19 of TrpA. Selected substitutions were also introduced at TrpA positions 2-6. The altered genes encoding these polypeptides were overexpressed from a foreign promoter on a multicopy plasmid and following insertion at their normal chromosomal location. Each deletion polypeptide was functional in vivo. However all appeared to be somewhat more labile and insoluble and less active enzymatically than wild type TrpA. The deletion polypeptides were overproduced and solubilized from cell debris by denaturation and refolding. Several were partially purified and assayed in various reactions in the presence of tryptophan synthetase beta2 (TrpB). The purified TrpADelta2-6 and TrpADelta2-11 deletion polypeptides had low activity in both the indole + serine --> tryptophan reaction and the indoleglycerol phosphate + serine --> tryptophan reaction. Poor activity in each reaction was partly due to reduced association of TrpA with TrpB. The addition of the TrpA ligands, alpha-glycerophosphate or indoleglycerol phosphate, during catalysis of the indole + serine --> tryptophan reaction increased association and activity. These findings suggest that removal of helix 0 of TrpA decreases TrpA-TrpB association as well as the activity of the TrpA active site. Alignment of the TrpA sequences from different species indicates that several lack part or all of helix 0. In some of these polypeptides, extra residues at the carboxyl end may substitute for helix 0.
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Affiliation(s)
- M C Yee
- Department of Biological Sciences, Stanford University, Stanford, California, 94305-5020, USA
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9
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10
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Woehl EU, Dunn MF. Monovalent metal ions play an essential role in catalysis and intersubunit communication in the tryptophan synthase bienzyme complex. Biochemistry 1995; 34:9466-76. [PMID: 7626617 DOI: 10.1021/bi00029a023] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This investigation shows that the alpha 2 beta 2 tryptophan synthase bienzyme complex from Salmonella typhimurium is subject to monovalent metal ion activation. The effects of the monovalent metal ions Na+ and K+ were investigated using rapid scanning stopped-flow (RSSF), single-wavelength stopped-flow (SWSF), and steady-state techniques. RSSF measurements of individual steps in the reaction of L-serine and indole to give L-trytophan (the beta-reaction) as well as the reaction of 3-indole-D-glycerol 3'-phosphate (IGP) with L-serine (the alpha beta-reaction) demonstrate that monovalent metal ions such as Na+ and K+ change the distribution of intermediates in both the transient and steady states. Therefore the metal ion effect alters relative ground-state energies and the relative positions of ground- and transition-state energies. The RSSF spectra and SWSF time courses show that the turnover of indole is significantly reduced in the absence of either Na+ or K+. The alpha-aminoacrylate Schiff base species, E(A-A), is in a less active state in the absence of monovalent metal ions. Na+ decreases the steady-state rate of IGP cleavage (the alpha-reaction) to about 30% of the value obtained in the absence of metal ions. Steady-state investigations show that in the absence of monovalent metal ions the alpha- and alpha beta-reactions have the same activity. Na+ binding gives a 30-fold stimulation of the alpha-reaction when the beta-site is in the E(A-A) form.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- E U Woehl
- Department of Biochemistry, University of California at Riverside 92521-0129, USA
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11
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Peracchi A, Mozzarelli A, Rossi GL. Monovalent cations affect dynamic and functional properties of the tryptophan synthase alpha 2 beta 2 complex. Biochemistry 1995; 34:9459-65. [PMID: 7626616 DOI: 10.1021/bi00029a022] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Monovalent cations affect both conformational and catalytic properties of the tryptophan synthase alpha 2 beta 2 complex from Salmonella typhimurium. Their influence on the dynamic properties of the enzyme was probed by monitoring the phosphorescence decay of the unique Trp-177 beta, a residue located near the beta-active site, at the interface between alpha- and beta-subunits. In the presence of either Li+, Na+, Cs+, or NH4+, the phosphorescence decay is biphasic and the average lifetime increases indicating a decrease in the flexibility of the N-terminal domain of the beta-subunit. Since amplitudes but not lifetimes are affected, cations appear to shift the equilibrium between preexisting enzyme conformations. The effect on the reaction between indole and L-serine was studied by steady state kinetic methods at room temperature. We found that cations: (i) bind to the L-serine--enzyme derivatives with an apparent dissociation constant, measured as the concentration of cation corresponding to one-half of the maximal activity, that is in the millimolar range and decreases with ion size; (ii) increase kcat with the order of efficacy Cs+ > K+ > Li+ > Na+; (iii) decrease KM for indole, Na+ being the most effective and causing a 30-fold decrease; and (iv) cause an increase of the kcat/KM ratio by 20-40-fold. The influence on the equilibrium distribution between the external aldimine and the alpha-aminoacrylate, intermediates in the reaction of L-serine with the beta-subunits of the enzyme, was found to be cation-specific.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- A Peracchi
- Istituto di Scienze Biochimiche, Università di Parma, Italy
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12
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Ruvinov SB, Ahmed SA, McPhie P, Miles EW. Monovalent cations partially repair a conformational defect in a mutant tryptophan synthase alpha 2 beta 2 complex (beta-E109A). J Biol Chem 1995; 270:17333-8. [PMID: 7615535 DOI: 10.1074/jbc.270.29.17333] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We are using the tryptophan synthase alpha 2 beta 2 complex as a model system to investigate how ligands, protein-protein interaction, and mutations regulate enzyme activity, reaction specificity, and substrate specificity. The rate of conversion of L-serine and indole to L-tryptophan by the beta 2 subunit alone is quite low, but is activated by certain monovalent cations or by association with alpha subunit to form an alpha 2 beta 2 complex. Since monovalent cations and alpha subunit appear to stabilize an active conformation of the beta 2 subunit, we have investigated the effects of monovalent cations on the activities and spectroscopic properties of a mutant form of alpha 2 beta 2 complex having beta 2 subunit glutamic acid 109 replaced by alanine (E109A). The E109A alpha 2 beta 2 complex is inactive in reactions with L-serine but active in reactions with beta-chloro-L-alanine. Parallel experiments show effects of monovalent cations on the properties of wild type beta 2 subunit and alpha 2 beta 2 complex. We find that CsCl stimulates the activity of the E109A alpha 2 beta 2 complex and of wild type beta 2 subunit with L-serine and indole and alters the equilibrium distribution of L-serine reaction intermediates. The results indicate that CsCl partially repairs the deleterious effects of the E109A mutation on the activity of the alpha 2 beta 2 complex by stabilizing a conformation with catalytic properties more similar to those of the wild type alpha 2 beta 2 complex. This conclusion is consistent with observations that monovalent cations alter the catalytic and spectroscopic properties of several pyridoxal phosphate-dependent enzymes by stabilizing alternative conformations.
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Affiliation(s)
- S B Ruvinov
- Laboratory of Biochemical Pharmacology, NIDDK, National Institutes of Health, Bethesda, Maryland 20892-0830, USA
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13
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Linkens H, Bartholmes P, Kaufmann M. The role of the hinge region of the beta 2-subunit in beta-replacement specificity of tryptophan synthase from Escherichia coli. Analysis of proteolytically modified beta species cleaved by endoproteinase Glu-C. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)36951-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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14
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Zhao G, Somerville R. A single amino acid switch within the “hinge” region of the tryptophan synthase beta subunit of Escherichia coli that leads to diminished association with alpha subunit and arrested conversion of ESII to product. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)82421-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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15
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Linkens HJ, Djavadi-Ohaniance L, Goldberg ME. Nicking of the tryptophan synthase beta 2-subunit at Glu-296 prevents the conformational change undergone on binding the alpha-subunit. FEBS Lett 1993; 320:224-8. [PMID: 8462690 DOI: 10.1016/0014-5793(93)80591-h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Using a monoclonal antibody as conformational probe it has been shown that the weakly active nicked-beta 2 dimer of tryptophan synthase generated by proteolytic cleavage at Glu-296, does not undergo on association with alpha subunit a conformational change known to occur in intact beta 2 subunit. This alpha induced conformational change is also prevented in intact beta 2 by the coenzyme pyridoxal-5'-phosphate when the substrate L-serine is absent.
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Affiliation(s)
- H J Linkens
- Unité de Biochimie Cellulaire, Institut Pasteur, Paris, France
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16
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Threonine 183 and adjacent flexible loop residues in the tryptophan synthase alpha subunit have critical roles in modulating the enzymatic activities of the beta subunit in the alpha 2 beta 2 complex. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)42548-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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17
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Zhao GP, Somerville RL. Genetic and biochemical characterization of the trpB8 mutation of Escherichia coli tryptophan synthase. An amino acid switch at the sharp turn of the trypsin-sensitive "hinge" region diminishes substrate binding and alters solubility. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)48527-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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18
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Eisenstein E. Cloning, expression, purification, and characterization of biosynthetic threonine deaminase from Escherichia coli. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(19)67668-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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19
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Djavadi-Ohaniance L, Friguet B, Goldberg ME. Conformational effects of ligand binding on the beta 2 subunit of Escherichia coli tryptophan synthase analyzed with monoclonal antibodies. Biochemistry 1986; 25:2502-8. [PMID: 3521735 DOI: 10.1021/bi00357a033] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Five monoclonal antibodies recognizing five different epitopes of the native beta 2 subunit of Escherichia coli tryptophan synthase (EC 4.1.2.20) were used to analyze the conformational changes occurring upon ligand binding or chemical modifications of the enzyme. For this purpose, the affinities of each antibody for the different forms of the enzyme were determined by using an enzyme-linked immunosorbent assay which allows measurement of the dissociation constant of antigen-antibody equilibrium in solution. The fixation of the coenzyme pyridoxal 5'-phosphate and the substrate L-serine modifies the affinity constants of most of the antibodies for the enzyme, thus showing the existence of extended conformational rearrangements of the protein. The association of the alpha subunit with the beta 2 subunit, which brings about an increase of the tryptophan synthase activity and abolishes the serine deaminase activity of beta 2, is accompanied by an important conformational change of the N-terminal domain of beta 2 (F1) since none of the anti-F1 monoclonal antibodies can bind to alpha 2 beta 2. Similarly, chemical modifications of beta 2 which are known to produce significant effects on the enzymatic activities of beta 2 result in changes of the affinities of the monoclonal antibodies which can be interpreted as the acquisition of different conformational states of the enzyme.
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20
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Srivastava DK, Bernhard SA. Enzyme-enzyme interactions and the regulation of metabolic reaction pathways. CURRENT TOPICS IN CELLULAR REGULATION 1986; 28:1-68. [PMID: 3539532 DOI: 10.1016/b978-0-12-152828-7.50003-2] [Citation(s) in RCA: 134] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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21
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Djavadi-Ohaniance L, Friguet B, Goldberg ME. Structural and functional influence of enzyme-antibody interactions: effects of eight different monoclonal antibodies on the enzymatic activity of Escherichia coli tryptophan synthase. Biochemistry 1984; 23:97-104. [PMID: 6419774 DOI: 10.1021/bi00296a016] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Twelve monoclonal antibodies directed against the beta 2 subunit of Escherichia coli tryptophan synthase (EC 4.2.1.20) were produced from hybridoma clones. These monoclonal antibodies are found to recognize at least eight different epitopes on beta 2, and eight classes of monoclonal antibodies are thus defined. The effects of these monoclonal antibodies on the enzymatic activities of beta 2 are studied. The monoclonal antibodies from three classes rapidly inhibit the serine deaminase activity catalyzed by the beta 2 subunit alone; two of them lead to an inhibition plateau under stoichiometric conditions, and their inhibitory effects are cumulative. With the antibodies from two of these three classes, the tryptophan synthase activity of the alpha 2 beta 2 complex is recovered, through a competition between the alpha subunit and the monoclonal antibody. On the contrary, the antibody from the third class is inhibitory even in the presence of an excess of alpha subunit. The antibodies from the five other classes, though binding easily to the coated antigen in the enzyme-linked immunosorbent assay, react only very slowly with beta 2 in solution and, only after a long time of incubation, inhibit the enzymatic activity at different levels.
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22
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Nihira T, Toraya T, Fukui S. Modification of tryptophanase with tetranitromethane. EUROPEAN JOURNAL OF BIOCHEMISTRY 1981; 119:273-7. [PMID: 7030734 DOI: 10.1111/j.1432-1033.1981.tb05604.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Modification of apotryptophanase with tetranitromethane [C(NO2)4] resulted in a loss of enzymatic activity, whereas holotryptophanase was highly resistant against C(NO2)4-inactivation. The essential importance of the active-site-bound pyridoxal 5'-phosphate (pyridoxal-P) for the protection was confirmed by the agreement of K 1/2 (protection) (1.2 microM) for pyridoxal-P with Km (1.5 microM) in enzyme catalysis. Amino acid analyses and inactivation stoichiometry showed that modification of 1--2 tyrosyl residues per monomer caused complete inactivation. The appearance of 430-nm species upon incubation of C(NO2)4-inactivated apoenzyme with pyridoxal-P indicated that the C(NO2)4-inactivated apoenzyme could still bind the coenzyme, although an affinity of the enzyme for pyridoxal-P (Kd = 51 microM) was much lower than that of the native enzyme (Kd = 0.7 microM). A close relationship was observed between the cofactor activity of monovalent cations and their effectiveness in the protection by pyridoxal-P: in the presence of active monovalent cations (K+, NH+4 and Rb+) pyridoxal-P could provide the protection but not in the presence of inactive cations (Li+, Na+ and Cs+) as well as in the absence of inorganic monovalent cations. From the experimental results obtained it was suggested strongly that tryptophanase has essential tyrosyl residues near the active site. The tyrosyl residues were prevented from the attack of C(NO2)4 by the active-site-bound pyridoxal-P only in the catalytically active holoenzyme.
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23
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Chaffotte AF, Zakin MM, Goldberg ME. Immunochemical studies on the evolution of tryptophanase and the two subunits of tryptophan synthetase of Escherichia coli K 12. Biochem Biophys Res Commun 1980; 92:381-8. [PMID: 6986866 DOI: 10.1016/0006-291x(80)90344-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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24
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Conformational and ligand binding properties of the isolated domains from the beta 2 subunit of Escherichia coli tryptophan synthetase investigated by the reactivity of their cysteines. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(18)36011-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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25
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Miles E, Higgins W. An active alpha'2beta2 derivative of tryptophean synthase formed by limited proteolysis. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)34609-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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26
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Veränderungen von Tryptophan-Synthase-, Indol-3-essigsäure-Oxidase- und Peroxidase-Aktivität im Verlauf der Entwicklung von Marchantia polymorpha L. ACTA ACUST UNITED AC 1978. [DOI: 10.1016/s0044-328x(78)80101-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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27
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Tryptophan synthase of Escherichia coli. Removal of pyridoxal 5'-phosphate and separation of the alpha and beta2 subunits. J Biol Chem 1977. [DOI: 10.1016/s0021-9258(17)39889-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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28
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Hodo HG, Murphy J, Hardman JK, Myers R. Substrate interactions with the alpha-subunit of the Escherichia coli tryptophan synthase. A kinetic study of the wild-type alpha-subunit. Arch Biochem Biophys 1977; 181:419-27. [PMID: 332076 DOI: 10.1016/0003-9861(77)90247-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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29
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TORAYA T, NIHIRA T, FUKUI S. Essential Role of Monovalent Cations in the Firm Binding of Pyridoxal 5'-Phosphate to Tryptophanase and beta-Tyrosinase. ACTA ACUST UNITED AC 1976. [DOI: 10.1111/j.1432-1033.1976.tb10925.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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30
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Berger FG, Herrmann KM. Tryptophan synthetase alpha(5.7-S): novel molecular species formed within Escherichia coli. J Bacteriol 1975; 124:800-9. [PMID: 1102532 PMCID: PMC235970 DOI: 10.1128/jb.124.2.800-809.1975] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
A novel molecular species contributes about 5% of the total tryptophan synthetase of Escherichia coli derepressed for the trp operon enzymes. The new species is identified under conditions in which the dissociation of the two nonidentical subunits of the tryptophan synthetase complex is favored. The new species sediments at 5.7S, catalyzes the conversion of indole-3-glycerol phosphate to indole, and has been designated alpha(5.7-S). Although alpha(5.7-S) is not observed in extracts of trpA or trpB mutant strains deficient in the ability to form tryptophan synthetase alpha or beta2 subunits, respectively, a mixture of the two extracts allows the formation of alpha(5.7-S). Similar results are obtained when a homogeneous alpha protein is mixed with an extract of a trpA mutant strain, suggesting that the interaction of alpha and beta2 proteins is obligatory for alpha(5.7-S) formation. One can obtain a beta2 protein preparation that when mixed with a pure alpha protein gives no alpha(5.7-S). Therefore, the interaction of alpha and beta2 proteins alone is not sufficient for the formation of alpha(5.7-S). When a mixture of alpha and beta2 proteins devoid of alpha(5.7-S) is added to extracts of trp deletion mutants, the novel species can be reconstituted in vitro only when deletions are used that carry at least the operator-proximal part of the trpB gene. Therefore, it is concluded that the alpha(5.7-S) species of tryptophan synthetase results from the interaction of the alpha protein, the beta2 protein, and a third component, beta', specified by the deoxyribonucleic acid defined by the end points of two trp deletion mutants.
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Adachi O, Kohn LD, Miles EW. Crystalline α2β2 Complexes of Tryptophan Synthetase of Escherichia coli. J Biol Chem 1974. [DOI: 10.1016/s0021-9258(19)42032-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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A Rapid Method for Preparing Crystalline b2 Subunit of Tryptophan Synthetase of Escherichia coli in High Yield. J Biol Chem 1974. [DOI: 10.1016/s0021-9258(20)79746-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Kida S, Crawford IP. Complementation in vitro between mutationally altered beta2 subunits of Escherichia coli tryptophan synthetase. J Bacteriol 1974; 118:551-9. [PMID: 4597448 PMCID: PMC246788 DOI: 10.1128/jb.118.2.551-559.1974] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Cross-reacting beta(2) subunits (CRMs) were purified from eight trpB missense mutants to test for complementation in vitro after urea dissociation and reaggregation. One CRM (B290, demonstrating "repairability," i.e., the appearance of enzymatic activity on combination with alpha subunits) was clearly positive with four others, all "non-repairable" CRMs resulting from mutations at three different but neighboring sites. One complementing pair, B290-B248, was studied in more detail and found, upon mixing purified proteins, to give complementation in the absence of denaturants. Complementation activity was low in each case. To study the mechanism of the modest increases in activity, we used a reduced beta(2) subunit as an artificial CRM to form hybrids where both the amount of activity due to complementation and the amount of hybrid could be measured. (In a reduced beta(2) subunit, the two pyridoxal phosphate cofactors have been chemically reduced by sodium borohydride and are covalently attached to lysine residues. This abolishes activity in the tryptophan synthetic reaction and causes the protein to migrate much faster than normal in acrylamide gel electrophoresis.) Reduced beta(2) subunit formed hybrid dimers with the non-repairable CRMs B244 and B248 at pH 6.0, but no enzymatic activity appeared. On the other hand, when reduced beta(2) subunit was mixed with B290 CRM at pH 6.0 to 6.6, an activity increase was seen that was proportional to the amount of hybrid. We conclude that hybrid formation is essential for complementation and that the mechanism of complementation in this system is the correction of a repairable active site on the B290 beta chain by a conformational change occuring when hybrid dimer is formed. This type of complementation must be restricted to a small class of CRMs having a conformationally deformed active site. From the amount of hybrid present and the increase in activity, a specific activity of 50 U/mg was calculated for the hybrid containing reduced and B290 beta chains. This value is slightly less than but close to the activity of the hybrid formed between reduced and normal beta chains, shown earlier to have half the specific activity of the normal dimer.
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Miles EW, McPhie P. Evidence for a Rate-determining Proton Abstraction in the Serine Deaminase Reaction of the β2 Subunit of Tryptophan Synthetase. J Biol Chem 1974. [DOI: 10.1016/s0021-9258(19)42708-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Miles EW, Kumagai H. Modification of Essential Histidyl Residues of the β2 Subunit of Tryptophan Synthetase by Photo-oxidation in the Presence of Pyridoxal 5′-Phosphate and l-Serine and by Diethylpyrocarbonate. J Biol Chem 1974. [DOI: 10.1016/s0021-9258(19)42707-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Schmauder H, Seidler M, Gröger D. Zur Kenntnis der Tryptophan-Synthase bei Claviceps, Stamm SD 58. ACTA ACUST UNITED AC 1974. [DOI: 10.1016/s0015-3796(17)30045-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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39
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Dicamelli RF, Balbinder E, Lebowitz J. Pressure effects on the association of the and 2 subunits of tryptophan synthetase from Escherichia coli and Salmonella typhimurium. Arch Biochem Biophys 1973; 155:315-24. [PMID: 4574541 DOI: 10.1016/0003-9861(73)90120-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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40
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Kredich NM, Keenan BS, Foote LJ. The Purification and Subunit Structure of Cysteine Desulfhydrase from Salmonella typhimurium. J Biol Chem 1972. [DOI: 10.1016/s0021-9258(19)44608-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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41
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Abstract
The five enzyme activities in the synthesis of l-tryptophan have been obtained in extracts of Euglena gracilis. One of these, tryptophan synthetase, has been studied in detail. The general catalytic properties of tryptophan synthetase, including the range of reactions catalyzed and its substrate and cofactor affinities, are similar to those reported for other organisms. The Euglena enzyme has two properties never previously observed for tryptophan synthetase. First, the rate of catalysis of the conversion of indole-glycerol phosphate to l-tryptophan remained at its maximal value and was unaffected by the ionic environment up to 0.3 m KCl. In contrast, the conversion of indole to tryptophan showed a sharp maximum at 0.08 m KCl. Second, the enzyme is a component of a complex that includes every enzyme in the pathway committed to tryptophan biosynthesis with the exception of anthranilate synthetase, the regulatory enzyme.
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Nagao RT, Moore TC. Partial purification and properties of tryptophan synthase of pea plants. Arch Biochem Biophys 1972; 149:402-13. [PMID: 4666111 DOI: 10.1016/0003-9861(72)90338-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Abstract
The two protein components of Pseudomonas putida tryptophan synthetase have been purified to homogeneity. Although there is general similarity between the Pseudomonas enzyme and that of the enteric bacteria, many differences were found. Components from Escherichia coli and P. putida do not stimulate each other enzymatically, and the enzymes differ in their response to monovalent cations. Serine deamination occurs best with the intact enzyme of P. putida, not with the beta(2) subunit alone as in E. coli. The amino acid compositions of the alpha subunits differ appreciably. These findings extend earlier studies showing differences between enteric organisms and pseudomonads in the regulation and genetic organization of the enzymes of the tryptophan pathway.
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The B protein of Escherichia coli tryptophan synthetase. II. New -elimination and -replacement reactions. Biochem Biophys Res Commun 1971; 44:1271-8. [PMID: 4946189 DOI: 10.1016/s0006-291x(71)80223-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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46
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Maurer R, Crawford IP. Properties and subunit structure of the B component of Pseudomonas putida tryptophan synthetase. Arch Biochem Biophys 1971; 144:193-203. [PMID: 5000700 DOI: 10.1016/0003-9861(71)90468-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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47
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Faeder EJ, Hammes GG. Kinetic studies of tryptophan synthetase. Interaction of L-serine, indole, and tryptophan with the native enzyme. Biochemistry 1971; 10:1041-5. [PMID: 4927802 DOI: 10.1021/bi00782a016] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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48
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Freedberg WB, Hardman JK. Structural and Functional Roles of the Cysteine Residues in the α Subunit of the Escherichia coli Tryptophan Synthetase. J Biol Chem 1971. [DOI: 10.1016/s0021-9258(19)76992-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Sakaguchi K. The similarity of tryptophan synthetases of Anabaena variabilis and Chlorella ellipsoidea with that of bacteria. BIOCHIMICA ET BIOPHYSICA ACTA 1970; 220:580-93. [PMID: 4993405 DOI: 10.1016/0005-2744(70)90288-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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