|Gene:||pabC||Accession Numbers: EG11493 (EcoCyc), b1096, ECK1082|
Component of: para-aminobenzoate synthase multi-enzyme complex (summary available)
Subunit composition of aminodeoxychorismate lyase = [PabC]2
PabC is an aminodeoxychorismate lyase that catalyzes the conversion of 4-amino-4-deoxychorismate to produce 4-aminobenzoate (p-aminobenzoate), and pyruvate in pathway 4-aminobenzoate biosynthesis [Green91a, Green92].
The reaction involves the elimination of pyruvate from 4-amino-4-deoxychorismate with concomitant aromatization of the cyclohexadiene ring. Aminodeoxychorismate lyase is classified as an α,β-lyase of the fold-type IV family. Its reaction mechanism with the pyridoxal 5'-phosphate cofactor has been studied [Jhee00a].
The crystal structure has been determined at 2.2 Å resolution [Nakai00].
The holoenzyme was shown to contain 1.26 mol of pyridoxal phosphate per subunit [Green92].
A pabC mutant was constructed and shown to require 4-aminobenzoate for growth [Green92].
|Map Position: [1,152,523 -> 1,153,332] (24.84 centisomes, 89°)||Length: 810 bp / 269 aa|
Molecular Weight of Polypeptide: 29.715 kD (from nucleotide sequence)
Unification Links: ASAP:ABE-0003709 , CGSC:31889 , DIP:DIP-10435N , EchoBASE:EB1456 , EcoGene:EG11493 , EcoliWiki:b1096 , ModBase:P28305 , OU-Microarray:b1096 , PortEco:pabC , PR:PRO_000023486 , Pride:P28305 , Protein Model Portal:P28305 , RefSeq:NP_415614 , RegulonDB:EG11493 , SMR:P28305 , String:511145.b1096 , UniProt:P28305
Relationship Links: InterPro:IN-FAMILY:IPR001544 , InterPro:IN-FAMILY:IPR017824 , InterPro:IN-FAMILY:IPR018300 , Panther:IN-FAMILY:PTHR11825 , PDB:Structure:1ET0 , PDB:Structure:1I2K , PDB:Structure:1I2L , Pfam:IN-FAMILY:PF01063 , Prosite:IN-FAMILY:PS00770
In Paralogous Gene Group: 254 (2 members)
|Biological Process:||GO:0008152 - metabolic process
GO:0046654 - tetrahydrofolate biosynthetic process [UniProtGOA12]
GO:0046656 - folic acid biosynthetic process [UniProtGOA11a, GOA01a]
|Molecular Function:||GO:0008696 - 4-amino-4-deoxychorismate lyase activity
[GOA01, GOA01a, Ye90, Green91a]
GO:0030170 - pyridoxal phosphate binding [GOA01a, Green92]
GO:0042803 - protein homodimerization activity [Green92]
GO:0003824 - catalytic activity [GOA01a]
GO:0016829 - lyase activity [UniProtGOA11a]
|Cellular Component:||GO:0005829 - cytosol [DiazMejia09]|
|MultiFun Terms:||metabolism → biosynthesis of building blocks → cofactors, small molecule carriers → folic acid|
|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 1% glycerol||Yes||37||Aerobic||7.2||0.35||Yes [Joyce06, Comment 3]|
|MOPS medium with 0.4% glucose||Yes||37||Aerobic||7.2||0.22||Yes [Baba06, Comment 2] |
Yes [Feist07, Comment 4]
Enzymatic reaction of: aminodeoxychorismate lyase
Synonyms: ADC lyase, 4-amino-4-deoxychorismate lyase
EC Number: 18.104.22.168
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction of enzyme catalysis.
This reaction is reversible.
Subunit of: para-aminobenzoate synthase multi-enzyme complex
Subunit composition of
para-aminobenzoate synthase multi-enzyme complex = [(PabB)(PabA)][(PabC)2]
4-amino-4-deoxychorismate synthase = (PabB)(PabA) (extended summary available)
aminodeoxychorismate lyase = (PabC)2 (summary available)
The three proteins PabA, PabB and PabC have been functionally described as three subunits of a 4-aminobenzoate (p-aminobenzoate) synthase multienzyme complex [Roux92]. Although no such complex has been isolated, the possibility of a ternary complex in vivo remains [Green92]. Together these proteins catalyze the conversion of glutamine and chorismate to 4-aminobenzoate, glutamate and pyruvate (see pathway 4-aminobenzoate biosynthesis).
10/20/97 Gene b1096 from Blattner lab Genbank (v. M52) entry merged into EcoCyc gene EG11493; confirmed by SwissProt match.
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
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
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
Green91a: Green JM, Nichols BP (1991). "p-Aminobenzoate biosynthesis in Escherichia coli. Purification of aminodeoxychorismate lyase and cloning of pabC." J Biol Chem 1991;266(20);12971-5. PMID: 2071583
Green92: Green JM, Merkel WK, Nichols BP (1992). "Characterization and sequence of Escherichia coli pabC, the gene encoding aminodeoxychorismate lyase, a pyridoxal phosphate-containing enzyme." J Bacteriol 1992;174(16);5317-23. PMID: 1644759
Jhee00a: Jhee KH, Yoshimura T, Miles EW, Takeda S, Miyahara I, Hirotsu K, Soda K, Kawata Y, Esaki N (2000). "Stereochemistry of the transamination reaction catalyzed by aminodeoxychorismate lyase from Escherichia coli: close relationship between fold type and stereochemistry." J Biochem 128(4);679-86. PMID: 11011151
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
Nakai00: Nakai T, Mizutani H, Miyahara I, Hirotsu K, Takeda S, Jhee KH, Yoshimura T, Esaki N (2000). "Three-dimensional structure of 4-amino-4-deoxychorismate lyase from Escherichia coli." J Biochem 128(1);29-38. PMID: 10876155
Roux92: Roux B, Walsh CT (1992). "p-aminobenzoate synthesis in Escherichia coli: kinetic and mechanistic characterization of the amidotransferase PabA." Biochemistry 1992;31(30);6904-10. PMID: 1637823
Ye90: Ye QZ, Liu J, Walsh CT (1990). "p-Aminobenzoate synthesis in Escherichia coli: purification and characterization of PabB as aminodeoxychorismate synthase and enzyme X as aminodeoxychorismate lyase." Proc Natl Acad Sci U S A 1990;87(23);9391-5. PMID: 2251281
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