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Escherichia coli K-12 substr. MG1655 Enzyme: chorismate mutase / prephenate dehydrogenase



Gene: tyrA Accession Numbers: EG11039 (EcoCyc), b2600, ECK2597

Synonyms: T-protein, chorismate mutase-prephenate dehydrogenase, chorismate mutase-prephenate:NAD+ oxidoreductase(decarboxylating)

Regulation Summary Diagram: ?

Subunit composition of chorismate mutase / prephenate dehydrogenase = [TyrA]2

Summary:
Bifunctional chorismate mutase / prephenate dehydrogenase (TyrA) carries out the shared first step in the parallel biosynthetic pathways for the aromatic amino acids tyrosine and phenylalanine, as well as the second step in tyrosine biosynthesis.

TyrA catalyzes both the conversion of chorismate into prephenate and the subsequent NAD+-dependent oxidative decarboxylation of prephenate [Pittard66, Sampathkumar82, Koch71, Koch71a].

The two catalytic activities of TyrA occur in separate portions of the protein, and are partially separable via mutation. Specifically, the chorismate mutase activity requires the amino-terminal portion of the protein, and the prephenate dehydrogenase activity is in the carboxy-terminal portion of the protein. Each isolated activity is markedly diminished when compared with its normal levels in whole TyrA [Chen03]. The dehydrogenase activity can also be deactivated via point mutations that disrupt NAD+ binding. These mutations do not, in turn, disable chorismate mutase function [Rood82, Maruya87]. A single sulfhydryl group within the protein is critical for both activities, despite their apparent localizations in different portions of the protein [Hudson84].

TyrA can occur as both a dimer and a tetramer. It is typically detected as an active dimer, and even the isolated amino- and carboy-terminal portions described above can dimerize independent of their missing halves [Rood82, Hudson84, Chen03]. A mol of dimerized TyrA can bind roughly one mol of NAD+, one mol of tyrosine, or one mol of prephenate. In the simultaneous presence of NAD+ and tyrosine, TyrA forms a tetramer rather than a dimer [Hudson83]. In addition to the 88 kD value, molecular weights of 78.8 kD for the dimer and 136 kD for the tetrameric form have been reported [Hudson83].

TyrA and engineered derivatives of TyrA have been used in metabolic engineering studies for the overproduction of L-tyrosine in Escherichia coli K-12. L-tyrosine is used in nutritional, pharmaceutical and industrial applications [Olson07, Patnaik08, LutkeEversloh07].

Gene Citations: [Garner85]

Locations: cytosol

Map Position: [2,736,970 <- 2,738,091] (58.99 centisomes)
Length: 1122 bp / 373 aa

Molecular Weight of Polypeptide: 42.042 kD (from nucleotide sequence)

Molecular Weight of Multimer: 88.0 kD (experimental) [Sampathkumar82]

pI: 5.3 [Sampathkumar82]

Unification Links: ASAP:ABE-0008547 , CGSC:58 , DIP:DIP-11059N , EchoBASE:EB1032 , EcoGene:EG11039 , EcoliWiki:b2600 , Mint:MINT-1255670 , ModBase:P07023 , OU-Microarray:b2600 , PortEco:tyrA , PR:PRO_000024150 , Pride:P07023 , Protein Model Portal:P07023 , RefSeq:NP_417091 , RegulonDB:EG11039 , SMR:P07023 , String:511145.b2600 , UniProt:P07023

Relationship Links: InterPro:IN-FAMILY:IPR002701 , InterPro:IN-FAMILY:IPR003099 , InterPro:IN-FAMILY:IPR008244 , InterPro:IN-FAMILY:IPR008927 , InterPro:IN-FAMILY:IPR011277 , InterPro:IN-FAMILY:IPR016040 , InterPro:IN-FAMILY:IPR020822 , Pfam:IN-FAMILY:PF01817 , Pfam:IN-FAMILY:PF02153 , Prosite:IN-FAMILY:PS51168 , Prosite:IN-FAMILY:PS51176 , Smart:IN-FAMILY:SM00830

In Paralogous Gene Group: 438 (2 members)

Gene-Reaction Schematic: ?

Genetic Regulation Schematic: ?

GO Terms:

Biological Process: GO:0006571 - tyrosine biosynthetic process Inferred from experiment Inferred by computational analysis [UniProtGOA12, UniProtGOA11a, GOA01a, Sampathkumar82]
GO:0009094 - L-phenylalanine biosynthetic process Inferred from experiment [Sampathkumar82]
GO:0008152 - metabolic process Inferred by computational analysis [UniProtGOA11a]
GO:0008652 - cellular amino acid biosynthetic process Inferred by computational analysis [UniProtGOA11a]
GO:0009073 - aromatic amino acid family biosynthetic process Inferred by computational analysis [UniProtGOA11a]
GO:0046417 - chorismate metabolic process Inferred by computational analysis [GOA01a]
GO:0055114 - oxidation-reduction process Inferred by computational analysis [UniProtGOA11a, GOA01a]
Molecular Function: GO:0004106 - chorismate mutase activity Inferred from experiment Inferred by computational analysis [GOA01, GOA01a, Sampathkumar82]
GO:0008977 - prephenate dehydrogenase activity Inferred from experiment Inferred by computational analysis [GOA01, GOA01a, Sampathkumar82]
GO:0042803 - protein homodimerization activity Inferred from experiment [Hudson84]
GO:0003824 - catalytic activity Inferred by computational analysis [UniProtGOA11a]
GO:0004665 - prephenate dehydrogenase (NADP+) activity Inferred by computational analysis [GOA01a]
GO:0016491 - oxidoreductase activity Inferred by computational analysis [UniProtGOA11a]
GO:0016853 - isomerase activity Inferred by computational analysis [UniProtGOA11a]
Cellular Component: GO:0005737 - cytoplasm Inferred by computational analysis [UniProtGOA11, UniProtGOA11a, GOA01a]
GO:0005829 - cytosol Inferred by computational analysis [DiazMejia09]

MultiFun Terms: metabolism biosynthesis of building blocks amino acids phenylalanine
metabolism biosynthesis of building blocks amino acids tyrosine

Essentiality data for tyrA knockouts: ?

Growth Medium Growth? T (°C) O2 pH Osm/L Growth Observations
LB enriched Yes 37 Aerobic 6.95   Yes [Gerdes03, Comment 1]
LB Lennox Yes 37 Aerobic 7   Yes [Baba06, Comment 2]
M9 medium with 0.4% glucose No 37 Aerobic 7.2 0.27 No [Patrick07, Comment 3]
M9 medium with 1% glycerol No 37 Aerobic 7.2 0.35 No [Joyce06]
MOPS medium with 0.4% glucose Indeterminate 37 Aerobic 7.2 0.22 Yes [Baba06, Comment 2]
No [Feist07, Comment 4]

Credits:
Curated 08-Apr-2008 by Shearer A , SRI International
Last-Curated ? 15-Jan-2010 by Fulcher C , SRI International


Enzymatic reaction of: chorismate mutase

EC Number: 5.4.99.5

chorismate <=> prephenate

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.

The reaction is favored in the direction shown.

In Pathways: superpathway of chorismate metabolism , superpathway of phenylalanine, tyrosine, and tryptophan biosynthesis , phenylalanine biosynthesis I , tyrosine biosynthesis I

Summary:
An alternate Km value of 140 µM has been reported for chorismate [Rood82].

The Km for chorismate has been reported to shift to 40 µM in the presence of NAD+ [Hudson83].

Tyrosine cooperatively inhibits chorismate mutase activity in the presence of NAD+, although it never surpasses 50% inhibition of the reaction. NAD+ and tyrosine both dramatically increase the affinity of the enzyme for each other [Hudson83]. Contrasting research has shown that tyrosine is only a marginal inhibitor of chorismate mutase activity [LutkeEversloh05].

Inhibitors (Unknown Mechanism): prephenate [Koch72] , L-tyrosine [Hudson83]

Primary Physiological Regulators of Enzyme Activity: L-tyrosine

Kinetic Parameters:

Substrate
Km (μM)
Citations
chorismate
92.0
[Hudson83]


Enzymatic reaction of: prephenate dehydrogenase

EC Number: 1.3.1.12

prephenate + NAD+ <=> 4-hydroxyphenylpyruvate + CO2 + NADH

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.

The reaction is favored in the direction shown.

In Pathways: superpathway of chorismate metabolism , superpathway of phenylalanine, tyrosine, and tryptophan biosynthesis , tyrosine biosynthesis I

Summary:
Tyrosine inhibits competitively with respect to prephenate, with a kI of 100 µM [Koch71, LutkeEversloh05, Hudson83].

Inhibitors (Competitive): L-tyrosine [Hudson83]

Primary Physiological Regulators of Enzyme Activity: L-tyrosine

Kinetic Parameters:

Substrate
Km (μM)
Citations
prephenate
130.0
[Rood82]


Sequence Features

Feature Class Location Citations Comment
Conserved-Region 1 -> 90
[UniProt09]
UniProt: Chorismate mutase;
Conserved-Region 99 -> 361
[UniProt09]
UniProt: Prephenate/arogenate dehydrogenase;


Gene Local Context (not to scale): ?

Transcription Unit:

Notes:

History:
10/20/97 Gene b2600 from Blattner lab Genbank (v. M52) entry merged into EcoCyc gene EG11039; confirmed by SwissProt match.


References

Baba06: Baba T, Ara T, Hasegawa M, Takai Y, Okumura Y, Baba M, Datsenko KA, Tomita M, Wanner BL, Mori H (2006). "Construction of Escherichia coli K-12 in-frame, single-gene knockout mutants: the Keio collection." Mol Syst Biol 2;2006.0008. PMID: 16738554

Chen03: Chen S, Vincent S, Wilson DB, Ganem B (2003). "Mapping of chorismate mutase and prephenate dehydrogenase domains in the Escherichia coli T-protein." Eur J Biochem 270(4);757-63. PMID: 12581215

DiazMejia09: Diaz-Mejia JJ, Babu M, Emili A (2009). "Computational and experimental approaches to chart the Escherichia coli cell-envelope-associated proteome and interactome." FEMS Microbiol Rev 33(1);66-97. PMID: 19054114

Feist07: Feist AM, Henry CS, Reed JL, Krummenacker M, Joyce AR, Karp PD, Broadbelt LJ, Hatzimanikatis V, Palsson BO (2007). "A genome-scale metabolic reconstruction for Escherichia coli K-12 MG1655 that accounts for 1260 ORFs and thermodynamic information." Mol Syst Biol 3;121. PMID: 17593909

Garner85: Garner CC, Herrmann KM (1985). "Operator mutations of the Escherichia coli aroF gene." J Biol Chem 260(6);3820-5. PMID: 2857723

Gerdes03: Gerdes SY, Scholle MD, Campbell JW, Balazsi G, Ravasz E, Daugherty MD, Somera AL, Kyrpides NC, Anderson I, Gelfand MS, Bhattacharya A, Kapatral V, D'Souza M, Baev MV, Grechkin Y, Mseeh F, Fonstein MY, Overbeek R, Barabasi AL, Oltvai ZN, Osterman AL (2003). "Experimental determination and system level analysis of essential genes in Escherichia coli MG1655." J Bacteriol 185(19);5673-84. PMID: 13129938

GOA01: GOA, MGI (2001). "Gene Ontology annotation based on Enzyme Commission mapping." Genomics 74;121-128.

GOA01a: GOA, DDB, FB, MGI, ZFIN (2001). "Gene Ontology annotation through association of InterPro records with GO terms."

Hudson83: Hudson GS, Howlett GJ, Davidson BE (1983). "The binding of tyrosine and NAD+ to chorismate mutase/prephenate dehydrogenase from Escherichia coli K12 and the effects of these ligands on the activity and self-association of the enzyme. Analysis in terms of a model." J Biol Chem 1983;258(5);3114-20. PMID: 6338013

Hudson84: Hudson GS, Wong V, Davidson BE (1984). "Chorismate mutase/prephenate dehydrogenase from Escherichia coli K12: purification, characterization, and identification of a reactive cysteine." Biochemistry 1984;23(25);6240-9. PMID: 6395895

Hudson84a: Hudson GS, Davidson BE (1984). "Nucleotide sequence and transcription of the phenylalanine and tyrosine operons of Escherichia coli K12." J Mol Biol 1984;180(4);1023-51. PMID: 6396419

Joyce06: Joyce AR, Reed JL, White A, Edwards R, Osterman A, Baba T, Mori H, Lesely SA, Palsson BO, Agarwalla S (2006). "Experimental and computational assessment of conditionally essential genes in Escherichia coli." J Bacteriol 188(23);8259-71. PMID: 17012394

Koch71: Koch GL, Shaw DC, Gibson F (1971). "The purification and characterisation of chorismate mutase-prephenate dehydrogenase from Escherichia coli K12." Biochim Biophys Acta 229(3);795-804. PMID: 4929151

Koch71a: Koch GL, Shaw DC, Gibson F (1971). "Characterisation of the subunits of chorismate mutase-prephenate dehydrogenase from Escherichia coli K12." Biochim Biophys Acta 229(3);805-12. PMID: 4929152

Koch72: Koch GL, Shaw DC, Gibson F (1972). "Studies on the relationship between the active sites of chorismate mutase-prephenate dehydrogenase from Escherichia coli or Aerobacter aerogenes." Biochim Biophys Acta 1972;258(3);719-30. PMID: 4552899

LutkeEversloh05: Lutke-Eversloh T, Stephanopoulos G (2005). "Feedback inhibition of chorismate mutase/prephenate dehydrogenase (TyrA) of Escherichia coli: generation and characterization of tyrosine-insensitive mutants." Appl Environ Microbiol 71(11);7224-8. PMID: 16269762

LutkeEversloh07: Lutke-Eversloh T, Stephanopoulos G (2007). "L-tyrosine production by deregulated strains of Escherichia coli." Appl Microbiol Biotechnol 75(1);103-10. PMID: 17221195

Maruya87: Maruya A, O'Connor MJ, Backman K (1987). "Genetic separability of the chorismate mutase and prephenate dehydrogenase components of the Escherichia coli tyrA gene product." J Bacteriol 169(10);4852-3. PMID: 3308859

Olson07: Olson MM, Templeton LJ, Suh W, Youderian P, Sariaslani FS, Gatenby AA, Van Dyk TK (2007). "Production of tyrosine from sucrose or glucose achieved by rapid genetic changes to phenylalanine-producing Escherichia coli strains." Appl Microbiol Biotechnol 74(5);1031-40. PMID: 17216463

Patnaik08: Patnaik R, Zolandz RR, Green DA, Kraynie DF (2008). "L-tyrosine production by recombinant Escherichia coli: fermentation optimization and recovery." Biotechnol Bioeng 99(4);741-52. PMID: 18069696

Patrick07: Patrick WM, Quandt EM, Swartzlander DB, Matsumura I (2007). "Multicopy suppression underpins metabolic evolvability." Mol Biol Evol 24(12);2716-22. PMID: 17884825

Pittard66: Pittard J, Wallace BJ (1966). "Distribution and function of genes concerned with aromatic biosynthesis in Escherichia coli." J Bacteriol 91(4);1494-508. PMID: 5326114

Rood82: Rood JI, Perrot B, Heyde E, Morrison JF (1982). "Characterization of monofunctional chorismate mutase/prephenate dehydrogenase enzymes obtained via mutagenesis of recombinant plasmids in vitro." Eur J Biochem 1982;124(3);513-9. PMID: 6809460

Sampathkumar82: Sampathkumar P, Morrison JF (1982). "Chorismate mutase-prephenate dehydrogenase from Escherichia coli. Purification and properties of the bifunctional enzyme." Biochim Biophys Acta 1982;702(2);204-11. PMID: 7044424

UniProt09: UniProt Consortium (2009). "UniProt version 15.8 released on 2009-10-01 00:00:00." Database.

UniProtGOA11: UniProt-GOA (2011). "Gene Ontology annotation based on the manual assignment of UniProtKB Subcellular Location terms in UniProtKB/Swiss-Prot entries."

UniProtGOA11a: UniProt-GOA (2011). "Gene Ontology annotation based on manual assignment of UniProtKB keywords in UniProtKB/Swiss-Prot entries."

UniProtGOA12: UniProt-GOA (2012). "Gene Ontology annotation based on UniPathway vocabulary mapping."

Other References Related to Gene Regulation

ClarkeCrutchfie87: Clarke-Crutchfield R (1987). "Education for motherhood at the turn of the century." Health Visit 60(5);151-3. PMID: 3294749

Cobbett87: Cobbett CS, Delbridge ML (1987). "Regulatory mutants of the aroF-tyrA operon of Escherichia coli K-12." J Bacteriol 1987;169(6);2500-6. PMID: 3294794

Cobbett88: Cobbett CS (1988). "Repression of the aroF promoter by the TyrR repressor in Escherichia coli K-12: role of the 'upstream' operator site." Mol Microbiol 1988;2(3);377-83. PMID: 3041242

DeFeyter86a: DeFeyter RC, Davidson BE, Pittard J (1986). "Nucleotide sequence of the transcription unit containing the aroL and aroM genes from Escherichia coli K-12." J Bacteriol 1986;165(1);233-9. PMID: 3001025

Mitchell03: Mitchell JE, Zheng D, Busby SJ, Minchin SD (2003). "Identification and analysis of 'extended -10' promoters in Escherichia coli." Nucleic Acids Res 31(16);4689-95. PMID: 12907708


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Please cite the following article in publications resulting from the use of EcoCyc: Nucleic Acids Research 41:D605-12 2013
Page generated by SRI International Pathway Tools version 18.5 on Sat Dec 27, 2014, biocyc11.