Escherichia coli K-12 substr. MG1655 Enzyme: aminodeoxychorismate lyase

Gene: pabC Accession Numbers: EG11493 (EcoCyc), b1096, ECK1082

Regulation Summary Diagram: ?

Regulation summary diagram for pabC

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 [Green91, 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 [Jhee00].

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].

Locations: cytosol

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)

pI: 6.47

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)

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

GO Terms:

Biological Process: GO:0008152 - metabolic process Inferred by computational analysis [GOA01a]
GO:0046654 - tetrahydrofolate biosynthetic process Inferred by computational analysis [UniProtGOA12]
GO:0046656 - folic acid biosynthetic process Inferred by computational analysis [UniProtGOA11a, GOA01a]
Molecular Function: GO:0008696 - 4-amino-4-deoxychorismate lyase activity Inferred from experiment Inferred by computational analysis [GOA01, GOA01a, Ye90, Green91]
GO:0030170 - pyridoxal phosphate binding Inferred from experiment Inferred by computational analysis [GOA01a, Green92]
GO:0042803 - protein homodimerization activity Inferred from experiment [Green92]
GO:0003824 - catalytic activity Inferred by computational analysis [GOA01a]
GO:0016829 - lyase activity Inferred by computational analysis [UniProtGOA11a]
Cellular Component: GO:0005829 - cytosol Inferred by computational analysis [DiazMejia09]

MultiFun Terms: metabolism biosynthesis of building blocks cofactors, small molecule carriers folic acid

Essentiality data for pabC 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 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]

Last-Curated ? 07-May-2012 by Fulcher C , SRI International

Enzymatic reaction of: aminodeoxychorismate lyase

Synonyms: ADC lyase, 4-amino-4-deoxychorismate lyase

EC Number:

4-amino-4-deoxychorismate <=> 4-aminobenzoate + pyruvate + H+

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.

In Pathways: superpathway of chorismate metabolism , superpathway of tetrahydrofolate biosynthesis , 4-aminobenzoate biosynthesis

Cofactors or Prosthetic Groups: pyridoxal 5'-phosphate [Green92]

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).

Last-Curated ? 07-May-2012 by Fulcher C , SRI International

Sequence Features

Protein sequence of pabC with features indicated

Feature Class Location Citations Comment
N6-pyridoxal-phosphate-Lys-Modification 140
UniProt: N6-(pyridoxal phosphate)lysine.

Gene Local Context (not to scale): ?

Gene local context diagram

Transcription Unit:

Transcription-unit diagram


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

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."

Green91: 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

Jhee00: 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

UniProt15: UniProt Consortium (2015). "UniProt version 2015-01 released on 2015-01-16 00:00:00." Database.

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."

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

Report Errors or Provide Feedback
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 19.0 on Fri Oct 9, 2015, BIOCYC14B.