Escherichia coli K-12 substr. MG1655 Enzyme: glutamate-pyruvate aminotransferase

Gene: alaC Accession Numbers: G7242 (EcoCyc), b2379, ECK2375

Synonyms: yfdZ

Regulation Summary Diagram: ?

Regulation summary diagram for alaC

Subunit composition of glutamate-pyruvate aminotransferase = [AlaC]2
         glutamate-pyruvate aminotransferase = AlaC

AlaC is one of three major alanine-synthesizing transaminases. AlaA and AlaC together account for 90% of glutamic-pyruvic transaminase (GPT) activity in the cell [Kim10].

A homology model of the enzyme based on the crystal structure of AlaA has been generated [PenaSoler14].

An alaC deletion strain has no growth defect, but an alaA avtA alaC triple mutant has a slow growth phenotype in liquid medium. The defect can be rescued by addition of alanine [Kim10, Yoneyama11]. Fitness and competitive growth experiments were performed under different growth conditions. Particularly under oxygen-limiting conditions, the doubling time of the ΔalaC strain in minimal media is increased compared to growth in rich media; unlike for the alaA and avtA mutants, addition of L-alanine returns the doubling time to that observed in DMEM medium. Under competitive growth conditions, the ΔalaC mutation confers a disadvantage compared to wild type even in rich media [PenaSoler14].

Expression of alaC is activated by the transcriptional regulator SgrR. AlaC may thus play a role in glucose-phosphate stress [Vanderpool07]. However, an alaC deletion mutant does not show altered sensitivity to α-methylglucoside, which induces sugar-phosphate stress [Kim10].

Locations: cytosol

Map Position: [2,495,079 <- 2,496,317] (53.78 centisomes, 194°)
Length: 1239 bp / 412 aa

Molecular Weight of Polypeptide: 46.216 kD (from nucleotide sequence)

Molecular Weight of Multimer: 87.0 kD (experimental) [Kim10]

Unification Links: ASAP:ABE-0007850 , DIP:DIP-12010N , EchoBASE:EB3950 , EcoGene:EG14198 , EcoliWiki:b2379 , ModBase:P77434 , OU-Microarray:b2379 , PortEco:yfdZ , Pride:P77434 , Protein Model Portal:P77434 , RefSeq:NP_416880 , RegulonDB:G7242 , SMR:P77434 , String:511145.b2379 , UniProt:P77434

Relationship Links: InterPro:IN-FAMILY:IPR004839 , InterPro:IN-FAMILY:IPR015421 , InterPro:IN-FAMILY:IPR015422 , InterPro:IN-FAMILY:IPR015424 , Pfam:IN-FAMILY:PF00155 , Prosite:IN-FAMILY:PS00105

In Paralogous Gene Group: 163 (5 members)

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

Genetic Regulation Schematic: ?

Genetic regulation schematic for alaC

GO Terms:

Biological Process: GO:0006523 - alanine biosynthetic process Inferred from experiment [Kim10]
GO:0019272 - L-alanine biosynthetic process from pyruvate Inferred from experiment [Yoneyama11, Kim10]
GO:0030632 - D-alanine biosynthetic process Inferred from experiment [Yoneyama11]
GO:0009058 - biosynthetic process Inferred by computational analysis [GOA01a]
Molecular Function: GO:0004021 - L-alanine:2-oxoglutarate aminotransferase activity Inferred from experiment Inferred by computational analysis [GOA01, Kim10]
GO:0008483 - transaminase activity Inferred from experiment Inferred by computational analysis [UniProtGOA11a, Kim10]
GO:0042803 - protein homodimerization activity Inferred from experiment [Kim10]
GO:0003824 - catalytic activity Inferred by computational analysis [GOA01a]
GO:0016740 - transferase activity Inferred by computational analysis [UniProtGOA11a]
GO:0030170 - pyridoxal phosphate binding Inferred by computational analysis [GOA01a]
Cellular Component: GO:0005737 - cytoplasm Inferred by computational analysis [UniProtGOA11, UniProtGOA11a]
GO:0005829 - cytosol Inferred by computational analysis [DiazMejia09]

MultiFun Terms: metabolism biosynthesis of building blocks amino acids alanine

Essentiality data for alaC 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]

Created 31-Aug-2010 by Keseler I , SRI International
Last-Curated ? 15-Jul-2014 by Keseler I , SRI International

Enzymatic reaction of: glutamate-pyruvate aminotransferase

EC Number:

2-oxoglutarate + L-alanine <=> L-glutamate + pyruvate

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

This reaction is reversible.

In Pathways: superpathway of L-alanine biosynthesis , L-alanine biosynthesis II

Kinetic Parameters:

Km (μM)

Sequence Features

Protein sequence of glutamate-pyruvate aminotransferase with features indicated

Feature Class Location Citations Comment
N6-pyridoxal-phosphate-Lys-Modification 244
UniProt: N6-(pyridoxal phosphate)lysine; Non-Experimental Qualifier: by similarity.

Gene Local Context (not to scale): ?

Gene local context diagram

Transcription Unit:

Transcription-unit diagram


Markus Krummenacker on Tue Oct 14, 1997:
Gene object created from Blattner lab Genbank (v. M52) entry.


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

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."

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

Kim10: Kim SH, Schneider BL, Reitzer L (2010). "Genetics and regulation of the major enzymes of alanine synthesis in Escherichia coli." J Bacteriol 192(20);5304-11. PMID: 20729367

PenaSoler14: Pena-Soler E, Fernandez FJ, Lopez-Estepa M, Garces F, Richardson AJ, Quintana JF, Rudd KE, Coll M, Vega MC (2014). "Structural Analysis and Mutant Growth Properties Reveal Distinctive Enzymatic and Cellular Roles for the Three Major L-Alanine Transaminases of Escherichia coli." PLoS One 9(7);e102139. PMID: 25014014

UniProt11a: UniProt Consortium (2011). "UniProt version 2011-11 released on 2011-11-22 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."

Vanderpool07: Vanderpool CK, Gottesman S (2007). "The novel transcription factor SgrR coordinates the response to glucose-phosphate stress." J Bacteriol 189(6);2238-48. PMID: 17209026

Yoneyama11: Yoneyama H, Hori H, Lim SJ, Murata T, Ando T, Isogai E, Katsumata R (2011). "Isolation of a Mutant Auxotrophic for L-Alanine and Identification of Three Major Aminotransferases That Synthesize L-Alanine in Escherichia coli." Biosci Biotechnol Biochem 75(5);930-8. PMID: 21597182

Other References Related to Gene Regulation

Huerta03: Huerta AM, Collado-Vides J (2003). "Sigma70 promoters in Escherichia coli: specific transcription in dense regions of overlapping promoter-like signals." J Mol Biol 333(2);261-78. PMID: 14529615

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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 19.0 on Fri Oct 9, 2015, biocyc13.