RegulonDB RegulonDB 11.1: Operon Form
   

accBC operon and associated TUs in Escherichia coli K-12 genome




Operon      
Name: accBC
This page displays every known transcription unit of this operon and their known regulation.


Transcription unit          
Name: accBC
Gene(s): accB, accC   Genome Browser M3D Gene expression COLOMBOS
Note(s): The accBC operon codes for two of the four proteins that conform acetyl-CoA carboxylase (ACC), the biotin carboxyl carrier protein (accB), and the biotin carboxylase (accC). The operon is located at min 72, separate from the other two protein-coding genes, accA (min 4.5) and accD (min 52.4) James ES,2004 The ACC product participates in the biosynthesis pathway of fatty acids. Since some of the acids are membrane lipids, the accBC operon expression is correlated with cell growth. Some peculiarities have been observed at the accBD upstream region: a long nontranslated leader region of 319 bp, a 98-bp sequence of bent DNA within this leader region, an unknown ORF of 188 bp, and a series of inverted repeats; but the only regulatory element that has been identified is AccB, which represses its own operon transcription James ES,2004
A potential RNA G-quadruplex structure, formed by guanine-rich sequences located in the coding sequence region of the gene, was identified for accC . This structure could regulate the expression of the gene, as observed for hemL gene expression Shao X, Zhang W, Umar MI, Wong HY, Seng Z, Xie Y, Zhang Y, Yang L, Kwok CK, Deng X,2020.
Evidence: [EXP-IDA-BOUNDARIES-DEFINED] Boundaries of transcription experimentally identified
Reference(s): [1] Karow M., et al., 1992
[2] Li SJ., et al., 1993
Promoter
Name: accBp1
+1: 3405140
Sigma Factor: Sigma70 Sigmulon
Distance from start of the gene: 296
Sequence: tgaaggttatttacatgttagctgttgattatcttccctgataagaccagtatttagctgCcaattgctacgaaatcgtta
                         -35                    -10         +1                   
Note(s): A bent DNA sequence of 98 bp within a nontranslated leader region and a 188-bp ORF are part of the accBD upstream region James ES,2004
Evidence: [COMP-AINF]
[COMP-HINF-POSITIONAL-IDENTIFICATION]
[EXP-IDA-TRANSCRIPTION-INIT-MAPPING]
Reference(s): [3] Huerta AM., et al., 2003
[4] Li SJ., et al., 1992
Terminator(s)
Type: rho-independent
Sequence: agcgtcaaaaGGCCGGATTTTCCGGCCttttttatta
Reference(s): [5] Vanet A., et al., 1993
TF binding sites (TFBSs)
[AccB,-] Phrase
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence Confidence level (C: Confirmed, S: Strong, W: Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
nd AccB repressor accBp1 nd nd nd nd nd [EXP-IEP-GENE-EXPRESSION-ANALYSIS], [EXP-IMP] W [6]


Transcription unit          
Name: accBC
Gene(s): accB, accC   Genome Browser M3D Gene expression COLOMBOS
Note(s): A potential RNA G-quadruplex structure, formed by guanine-rich sequences located in the coding sequence region of the gene, was identified for accC . This structure could regulate the expression of the gene, as observed for hemL gene expression Shao X, Zhang W, Umar MI, Wong HY, Seng Z, Xie Y, Zhang Y, Yang L, Kwok CK, Deng X,2020.
Evidence: [EXP-IDA-BOUNDARIES-DEFINED] Boundaries of transcription experimentally identified
Reference(s): [7] My L., et al., 2015
[5] Vanet A., et al., 1993
Promoter
Name: accBp2
+1: 3405172
Distance from start of the gene: 264
Sequence: cttccctgataagaccagtatttagctgccaattgctacgaaatcgttataatgtgcgacCtcgtcctccctgacgcagtt
Evidence: [EXP-IDA-TRANSCRIPTION-INIT-MAPPING]
Reference(s): [7] My L., et al., 2015
Terminator(s)
Type: rho-independent
Sequence: agcgtcaaaaGGCCGGATTTTCCGGCCttttttatta
Reference(s): [5] Vanet A., et al., 1993
TF binding sites (TFBSs)
[FadR,+] Phrase
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence Confidence level (C: Confirmed, S: Strong, W: Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
proximal FadR activator accBp2 3405115 3405131 -49.0 tgattatcttCCCTGATAAGACCAGTAtttagctgcc nd [EXP-IEP-GENE-EXPRESSION-ANALYSIS], [COMP-AINF-SIMILAR-TO-CONSENSUS], [EXP-IDA-BINDING-OF-PURIFIED-PROTEINS] W [7]


Evidence    

 [COMP-AINF] Inferred computationally without human oversight

 [COMP-HINF-POSITIONAL-IDENTIFICATION] Human inference of promoter position

 [EXP-IDA-TRANSCRIPTION-INIT-MAPPING] Transcription initiation mapping

 [EXP-IEP-GENE-EXPRESSION-ANALYSIS] Gene expression analysis

 [EXP-IMP] Inferred from mutant phenotype

 [COMP-AINF-SIMILAR-TO-CONSENSUS] Automated inference based on similarity to consensus sequences

 [EXP-IDA-BINDING-OF-PURIFIED-PROTEINS] Binding of purified proteins


Reference(s)    

 [1] Karow M., Fayet O., Georgopoulos C., 1992, The lethal phenotype caused by null mutations in the Escherichia coli htrB gene is suppressed by mutations in the accBC operon, encoding two subunits of acetyl coenzyme A carboxylase., J Bacteriol 174(22):7407-18

 [2] Li SJ., Cronan JE., 1993, Growth rate regulation of Escherichia coli acetyl coenzyme A carboxylase, which catalyzes the first committed step of lipid biosynthesis., J Bacteriol 175(2):332-40

 [3] 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

 [4] Li SJ., Cronan JE., 1992, The gene encoding the biotin carboxylase subunit of Escherichia coli acetyl-CoA carboxylase., J Biol Chem 267(2):855-63

 [5] Vanet A., Plumbridge JA., Alix JH., 1993, Cotranscription of two genes necessary for ribosomal protein L11 methylation (prmA) and pantothenate transport (panF) in Escherichia coli K-12., J Bacteriol 175(22):7178-88

 [6] James ES., Cronan JE., 2004, Expression of two Escherichia coli acetyl-CoA carboxylase subunits is autoregulated., J Biol Chem 279(4):2520-7

 [7] My L., Ghandour Achkar N., Viala JP., Bouveret E., 2015, Reassessment of the Genetic Regulation of Fatty Acid Synthesis in Escherichia coli: Global Positive Control by the Dual Functional Regulator FadR., J Bacteriol 197(11):1862-72

RegulonDB