RegulonDB RegulonDB 10.6.3: Operon Form
   

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




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


Transcription unit          
Name: lacZYA
Synonym(s): OP00045, lacAYZ
Gene(s): lacA, lacY, lacZ   Genome Browser M3D Gene expression COLOMBOS
Note(s): The lac operon is controlled by four promoters, P1, which is the principal promoter, P2, and P3 and P4, the weaker promoters |CITS:[1649816][1650341]|. Transcription of this operon is both negatively and positively regulated. Negative regulation occurs when the lac repressor (LacI) binds to the operator, preventing transcription by RNA polymerase |CITS:[6259624][2166165]|. Positive regulation is mediated by the cAMP receptor protein, CRP (also referred to as the catabolite activator protein, CAP) |CITS:[1649816][1650341][15385551]|.
In the presence of glucose, lac operon expression is not needed and a control mechanism known as catabolite repression occurs. This refers to the ability of glucose to inhibit expression of the operon. As cellular cAMP levels drop in response to glucose uptake, CRP is not activated and operon expression is inhibited. Under this mechanism, lac genes are only expressed if lactose is present and glucose is absent.
In the absence of glucose, the levels of cAMP increase and this metabolite binds to CRP. CRP becomes active and it binds to DNA near the lac promoter, facilitating transcription |CITS:[6259624][2166165]|. Synthesis of the lac operon proteins is induced when E. coli is grown on lactose in the absence of glucose. CRP is the principal activator of the lac operon. It stimulates transcription of p2, increasing the affinity for the RNA polymerase |CITS:[2166165][1650341]|. The p2 is a class II promoter, and CRP activates transcription of class II CRP-dependent promoters by overlapping the -35 box of the core promoter; the central position of the binding site is located near -41.5 |CITS:[17073754][8735277][8604346]|. In the same way, CRP completely overlaps p1 and p3, avoiding RNA polymerase binding and preventing transcription of these promoters |CITS:[2166165][1650341]|.
On the other hand, in the absence of allolactose, the LacI repressor represses the lac operon |CITS:[2166165][15950160]|. In this repression system, LacI binds to two operators centered at positions 10 bp (O1) and -82 bp (O3), and formation of the repressor loop is critical |CITS:[8984648][ 8984647][14725772][2166165]|. Expression of p1 is also stimulated when LacI binds to O1 |CITS:[2166165]|.
Induction occurs when the physiological inducer, allolactose, binds to the lac repressor, preventing it from binding to the operator |CITS:[2166165][15950160]|. Nonphysiological analogs, such as thiogalactosides, can function as inducers too. Activation of the lac operon can also be partially increased by CRP when it overlaps the O1 site, acting as an antirepressor |CITS:[3315229][2166165]|.
In single-cell experiments, total induction of the lac operon produces a constant distribution in the production of mRNA molecules in all growth phases, except in the exponential phase, where two mRNA populations are present |CITS:[25626902]|.
Considering the activation site of the lac operon like the upstream activation region of the promoter sequence (URS) and the operator region like downstream derepression region of the promoter sequence (DRS), the independent URS activation produces a small number of mRNA molecules compared to DRS activation. This behavior corresponds to early stages of cell growth and later stages, respectively. However, it is probable that in the exponential phase URS and DRS work coordinately in the transcription of the lac operon |CITS:[ 25626902]|.
A mutation in the HU protein that generates positive superhelicity causes repression of the lac operon |CITS:[ 21896677]|.
Evidence: [BTEI] Boundaries of transcription experimentally identified
[LTED] Length of transcript experimentally determined
[LTED] Length of transcript experimentally determined
Reference(s): [1] McCormick JR., et al., 1991
[2] Murakawa GJ., et al., 1991
Promoter
Name: lacZp1
+1: 366343
Sigma Factor: Sigma70 Sigmulon
Distance from start of the gene: 38
Sequence: gctcactcattaggcaccccaggctttacactttatgcttccggctcgtatgttgtgtggAattgtgagcggataacaatt
                         -10                     -35        +1                   
Note(s): lac operon expression was studied during diauxic shift; although it was supposed to be under σS control (as σS is the main sigma factor for cell adaptation during this change), no σS site has been found in this promoter, nor is there a reported correlation of lac expression with σS WT or deleted Fischer D, Teich A, Neubauer P, Hengge-Aronis R,1998
Insulation of the lac promoter was tested by Sasson et al. in 2012 Sasson V, Shachrai I, Bren A, Dekel E, Alon U,2012 In that study, activators showed better insulation at high expression levels and repressors showed better insulation at low expression levels, following Savageau's rule, in which Escherichia coli genes that are needed often in the natural environment tend to be regulated by activators and those genes that are rarely needed are regulated by repressors Savageau MA,1974. Sasson V, Shachrai I, Bren A, Dekel E, Alon U,2012
Evidence: [TIM]
Reference(s): [3] Belliveau NM., et al., 2018
[4] Cannistraro VJ., et al., 1985
[5] Czarniecki D., et al., 1997
[6] Xiong XF., et al., 1991
Terminator(s)
Type: rho-independent
Sequence: gaacttgtagGCCTGATAAGCGCAGCGTATCAGGCaatttttata
Reference(s): [7] Sung YC., et al., 1988
Type: rho-independent
Sequence: gggtcaaagaGGCATGATGCGACGCTTGTTCCTGCGCTTTGTTCATGCCGgatgcggcta
Reference(s): [8] Hediger MA., et al., 1985
TF binding sites (TFBSs)
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence (Confirmed, Strong, Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
proximal CRP-cAMP1 activator lacZp1 366322 366343 11.5 tgttgtgtggAATTGTGAGCGGATAACAATTTcacacaggaa nd [BPP], [HIBSCS] [24], [25], [26]
proximal CRP-cAMP2 activator lacZp1 366394 366415 -61.5 gcaacgcaatTAATGTGAGTTAGCTCACTCATtaggcacccc nd [BPP], [GEA], [HIBSCS], [SM] [3], [5], [6], [15], [16], [17], [18], [19], [20]
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence (Confirmed, Strong, Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
proximal H-NS repressor lacZp1 366313 366327 24.0 gagcggataaCAATTTCACACAGGAaacagctatg nd [BPP] [13], [14]
proximal H-NS repressor lacZp1 366331 366345 6.0 tatgttgtgtGGAATTGTGAGCGGAtaacaatttc nd [BPP] [13], [14]
proximal H-NS repressor lacZp1 366341 366355 -5.0 ttccggctcgTATGTTGTGTGGAATtgtgagcgga nd [BPP] [13], [14]
proximal H-NS repressor lacZp1 366367 366381 -31.0 ggcaccccagGCTTTACACTTTATGcttccggctc nd [BPP] [13], [14]
proximal H-NS repressor lacZp1 366390 366404 -54.0 aatgtgagttAGCTCACTCATTAGGcaccccaggc nd [BPP] [13], [14]
proximal H-NS repressor lacZp1 366403 366417 -67.0 gcgcaacgcaATTAATGTGAGTTAGctcactcatt nd [BPP] [13], [14]
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence (Confirmed, Strong, Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
remote LacI repressor lacZp1 365922 365942 412.0 gaatccgacgGGTTGTTACTCGCTCACATTTaatgttgatg nd , [HIBSCS], [SM] [9], [11], [12], [22]
proximal LacI repressor lacZp1 366323 366343 11.0 tgttgtgtggAATTGTGAGCGGATAACAATTtcacacagga nd [BPP], [GEA], , [HIBSCS], [SM] [3], [9], [11], [12], [21], [22], [23]
proximal LacI repressor lacZp1 366415 366435 -82.0 ctggaaagcgGGCAGTGAGCGCAACGCAATTaatgtgagtt nd , [HIBSCS], [SM] [9], [10], [11], [12]
Note(s): 1The CRP-binding site controlling the lacZp1 promoter was enhanced up to 14-fold or abolished by varying the N6 spacer sequence, which is part of the consensus sequence of the dimer that recognizes a 20-bp region through direct amino acid nucleotide interactions in the major groove of the two operator half-sites Lindemose S, Nielsen PE, Valentin-Hansen P, Møllegaard NE,2014
Crystal structure analyses revealed that the interaction results in two strong kinks at the TG/CA steps closest to the 6-bp spacer (N6), and the authors proposed that the underlying mechanism relies on N6 deformability Lindemose S, Nielsen PE, Valentin-Hansen P, Møllegaard NE,2014
2The CRP-binding site controlling the lacZp1 promoter was enhanced up to 14-fold or abolished by varying the N6 spacer sequence, which is part of the consensus sequence of the dimer that recognizes a 20-bp region through direct amino acid nucleotide interactions in the major groove of the two operator half-sites Lindemose S, Nielsen PE, Valentin-Hansen P, Møllegaard NE,2014
Crystal structure analyses revealed that the interaction results in two strong kinks at the TG/CA steps closest to the 6-bp spacer (N6), and the authors proposed that the underlying mechanism relies on N6 deformability Lindemose S, Nielsen PE, Valentin-Hansen P, Møllegaard NE,20143The CRP-binding site controlling the lacZp1 promoter was enhanced up to 14-fold or abolished by varying the N6 spacer sequence, which is part of the consensus sequence of the dimer that recognizes a 20-bp region through direct amino acid nucleotide interactions in the major groove of the two operator half-sites Lindemose S, Nielsen PE, Valentin-Hansen P, Møllegaard NE,2014
Crystal structure analyses revealed that the interaction results in two strong kinks at the TG/CA steps closest to the 6-bp spacer (N6), and the authors proposed that the underlying mechanism relies on N6 deformability Lindemose S, Nielsen PE, Valentin-Hansen P, Møllegaard NE,2014
9The CRP-binding site controlling the lacZp1 promoter was enhanced up to 14-fold or abolished by varying the N6 spacer sequence, which is part of the consensus sequence of the dimer that recognizes a 20-bp region through direct amino acid nucleotide interactions in the major groove of the two operator half-sites Lindemose S, Nielsen PE, Valentin-Hansen P, Møllegaard NE,2014
Crystal structure analyses revealed that the interaction results in two strong kinks at the TG/CA steps closest to the 6-bp spacer (N6), and the authors proposed that the underlying mechanism relies on N6 deformability Lindemose S, Nielsen PE, Valentin-Hansen P, Møllegaard NE,2014


Transcription unit          
Name: lacZYA
Synonym(s): lacZ
Gene(s): lacA, lacY, lacZ   Genome Browser M3D Gene expression COLOMBOS
Note(s): The lac operon is controlled by four promoters, P1, which is the principal promoter, P2, and P3 and P4, the weaker promoters |CITS:[1649816][1650341]|. Transcription of this operon is both negatively and positively regulated. Negative regulation occurs when the lac repressor (LacI) binds to the operator, preventing transcription by RNA polymerase |CITS:[6259624][2166165]|. Positive regulation is mediated by the cAMP receptor protein, CRP (also referred to as the catabolite activator protein, CAP) |CITS:[1649816][1650341][15385551]|.
In the presence of glucose, lac operon expression is not needed and a control mechanism known as catabolite repression occurs. This refers to the ability of glucose to inhibit expression of the operon. As cellular cAMP levels drop in response to glucose uptake, CRP is not activated and operon expression is inhibited. Under this mechanism, lac genes are only expressed if lactose is present and glucose is absent.
In the absence of glucose, the levels of cAMP increase and this metabolite binds to CRP. CRP becomes active and it binds to DNA near the lac promoter, facilitating transcription |CITS:[6259624][2166165]|. Synthesis of the lac operon proteins is induced when E. coli is grown on lactose in the absence of glucose. CRP is the principal activator of the lac operon. It stimulates transcription of p2, increasing the affinity for the RNA polymerase |CITS:[2166165][1650341]|. The p2 is a class II promoter, and CRP activates transcription of class II CRP-dependent promoters by overlapping the -35 box of the core promoter; the central position of the binding site is located near -41.5 |CITS:[17073754][8735277][8604346]|. In the same way, CRP completely overlaps p1 and p3, avoiding RNA polymerase binding and preventing transcription of these promoters |CITS:[2166165][1650341]|.
On the other hand, in the absence of allolactose, the LacI repressor represses the lac operon |CITS:[2166165][15950160]|. In this repression system, LacI binds to two operators centered at positions 10 bp (O1) and -82 bp (O3), and formation of the repressor loop is critical |CITS:[8984648][ 8984647][14725772][2166165]|. Expression of p1 is also stimulated when LacI binds to O1 |CITS:[2166165]|.
Induction occurs when the physiological inducer, allolactose, binds to the lac repressor, preventing it from binding to the operator |CITS:[2166165][15950160]|. Nonphysiological analogs, such as thiogalactosides, can function as inducers too. Activation of the lac operon can also be partly increased by CRP when it overlaps the O1 site, acting as an antirepressor |CITS:[3315229][2166165]|.
Evidence: [ITCR] Inferred through co-regulation
[LTED] Length of transcript experimentally determined
[LTED] Length of transcript experimentally determined
Reference(s): [1] McCormick JR., et al., 1991
[2] Murakawa GJ., et al., 1991
Promoter
Name: lacZp3
+1: 366358
Distance from start of the gene: 53
Sequence: aattaatgtgagttagctcactcattaggcaccccaggctttacactttatgcttccggcTcgtatgttgtgtggaattgt
Evidence: [TIM]
Reference(s): [5] Czarniecki D., et al., 1997
[6] Xiong XF., et al., 1991
Terminator(s)
Type: rho-independent
Sequence: gaacttgtagGCCTGATAAGCGCAGCGTATCAGGCaatttttata
Reference(s): [7] Sung YC., et al., 1988
Type: rho-independent
Sequence: gggtcaaagaGGCATGATGCGACGCTTGTTCCTGCGCTTTGTTCATGCCGgatgcggcta
Reference(s): [8] Hediger MA., et al., 1985
TF binding sites (TFBSs)
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence (Confirmed, Strong, Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
proximal CRP-cAMP repressor lacZp3 366322 366343 26.5 tgttgtgtggAATTGTGAGCGGATAACAATTTcacacaggaa nd [BPP], [HIBSCS] [24], [25], [26]
proximal CRP-cAMP repressor lacZp3 366394 366415 -46.5 gcaacgcaatTAATGTGAGTTAGCTCACTCATtaggcacccc nd [BPP], [GEA], [HIBSCS], [SM] [3], [5], [6], [15], [16], [17], [18], [19], [20]


Transcription unit          
Name: lacZYA
Gene(s): lacA, lacY, lacZ   Genome Browser M3D Gene expression COLOMBOS
Note(s): The lac operon is controlled by four promoters, P1, which is the principal promoter, P2, and P3 and P4, the weaker promoters |CITS:[1649816][1650341]|. Transcription of this operon is both negatively and positively regulated. Negative regulation occurs when the lac repressor (LacI) binds to the operator, preventing transcription by RNA polymerase |CITS:[6259624][2166165]|. Positive regulation is mediated by the cAMP receptor protein, CRP (also referred to as the catabolite activator protein, CAP) |CITS:[1649816][1650341][15385551]|.
In the presence of glucose, lac operon expression is not needed and a control mechanism known as catabolite repression occurs. This refers to the ability of glucose to inhibit expression of the operon. As cellular cAMP levels drop in response to glucose uptake, CRP is not activated and operon expression is inhibited. Under this mechanism, lac genes are only expressed if lactose is present and glucose is absent.
In the absence of glucose, the levels of cAMP increase and this metabolite binds to CRP. CRP becomes active and it binds to DNA near the lac promoter, facilitating transcription |CITS:[6259624][2166165]|. Synthesis of the lac operon proteins is induced when E. coli is grown on lactose in the absence of glucose. CRP is the principal activator of the lac operon. It stimulates transcription of p2, increasing the affinity for the RNA polymerase |CITS:[2166165][1650341]|. The p2 is a class II promoter, and CRP activates transcription of class II CRP-dependent promoters by overlapping the -35 box of the core promoter; the central position of the binding site is located near -41.5 |CITS:[17073754][8735277][8604346]|. In the same way, CRP completely overlaps p1 and p3, avoiding RNA polymerase binding and preventing transcription of these promoters |CITS:[2166165][1650341]|.
On the other hand, in the absence of allolactose, the LacI repressor represses the lac operon |CITS:[2166165][15950160]|. In this repression system, LacI binds to two operators centered at positions 10 bp (O1) and -82 bp (O3), and formation of the repressor loop is critical |CITS:[8984648][ 8984647][14725772][2166165]|. Expression of p1 is also stimulated when LacI binds to O1 |CITS:[2166165]|.
Induction occurs when the physiological inducer, allolactose, binds to the lac repressor, preventing it from binding to the operator |CITS:[2166165][15950160]|. Nonphysiological analogs, such as thiogalactosides, can function as inducers too. Activation of the lac operon can also be partly increased by CRP when it overlaps the O1 site, acting as an antirepressor |CITS:[3315229][2166165]|.
Evidence: [ITCR] Inferred through co-regulation
[LTED] Length of transcript experimentally determined
[LTED] Length of transcript experimentally determined
Reference(s): [1] McCormick JR., et al., 1991
[2] Murakawa GJ., et al., 1991
Promoter
Name: lacZp2
+1: 366365
Distance from start of the gene: 60
Sequence: gcaacgcaattaatgtgagttagctcactcattaggcaccccaggctttacactttatgcTtccggctcgtatgttgtgtg
Evidence: [TIM]
Reference(s): [5] Czarniecki D., et al., 1997
[6] Xiong XF., et al., 1991
Terminator(s)
Type: rho-independent
Sequence: gaacttgtagGCCTGATAAGCGCAGCGTATCAGGCaatttttata
Reference(s): [7] Sung YC., et al., 1988
Type: rho-independent
Sequence: gggtcaaagaGGCATGATGCGACGCTTGTTCCTGCGCTTTGTTCATGCCGgatgcggcta
Reference(s): [8] Hediger MA., et al., 1985
TF binding sites (TFBSs)
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence (Confirmed, Strong, Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
remote CRP-cAMP repressor lacZp2 366322 366343 33.5 tgttgtgtggAATTGTGAGCGGATAACAATTTcacacaggaa nd [BPP], [HIBSCS] [24], [25], [26]
proximal CRP-cAMP repressor lacZp2 366394 366415 -39.5 gcaacgcaatTAATGTGAGTTAGCTCACTCATtaggcacccc nd [BPP], [GEA], [HIBSCS], [SM] [3], [5], [6], [15], [16], [17], [18], [19], [20]


Transcription unit       
Name: lacZYA
Gene(s): lacA, lacY, lacZ   Genome Browser M3D Gene expression COLOMBOS
Note(s): The lac operon is controlled by four promoters, P1, which is the principal promoter, P2, and P3 and P4, the weaker promoters |CITS:[1649816][1650341]|. Transcription of this operon is both negatively and positively regulated. Negative regulation occurs when the lac repressor (LacI) binds to the operator, preventing transcription by RNA polymerase |CITS:[6259624][2166165]|. Positive regulation is mediated by the cAMP receptor protein, CRP (also referred to as the catabolite activator protein, CAP) |CITS:[1649816][1650341][15385551]|.
In the presence of glucose, lac operon expression is not needed and a control mechanism known as catabolite repression occurs. This refers to the ability of glucose to inhibit expression of the operon. As cellular cAMP levels drop in response to glucose uptake, CRP is not activated and operon expression is inhibited. Under this mechanism, lac genes are only expressed if lactose is present and glucose is absent.
In the absence of glucose, the levels of cAMP increase and this metabolite binds to CRP. CRP becomes active and it binds to DNA near the lac promoter, facilitating transcription |CITS:[6259624][2166165]|. Synthesis of the lac operon proteins is induced when E. coli is grown on lactose in the absence of glucose. CRP is the principal activator of the lac operon. It stimulates transcription of p2, increasing the affinity for the RNA polymerase |CITS:[2166165][1650341]|. The p2 is a class II promoter, and CRP activates transcription of class II CRP-dependent promoters by overlapping the -35 box of the core promoter; the central position of the binding site is located near -41.5 |CITS:[17073754][8735277][8604346]|. In the same way, CRP completely overlaps p1 and p3, avoiding RNA polymerase binding and preventing transcription of these promoters |CITS:[2166165][1650341]|.
On the other hand, in the absence of allolactose, the LacI repressor represses the lac operon |CITS:[2166165][15950160]|. In this repression system, LacI binds to two operators centered at positions 10 bp (O1) and -82 bp (O3), and formation of the repressor loop is critical |CITS:[8984648][ 8984647][14725772][2166165]|. Expression of p1 is also stimulated when LacI binds to O1 |CITS:[2166165]|.
Induction occurs when the physiological inducer, allolactose, binds to the lac repressor, preventing it from binding to the operator |CITS:[2166165][15950160]|. Nonphysiological analogs, such as thiogalactosides, can function as inducers too. Activation of the lac operon can also be partly increased by CRP when it overlaps the O1 site, acting as an antirepressor |CITS:[3315229][2166165]|.
Evidence: [ITCR] Inferred through co-regulation
[LTED] Length of transcript experimentally determined
[LTED] Length of transcript experimentally determined
Reference(s): [1] McCormick JR., et al., 1991
[2] Murakawa GJ., et al., 1991
Promoter
Name: lacZp4
+1: 366377
Distance from start of the gene: 72
Sequence: cgggcagtgagcgcaacgcaattaatgtgagttagctcactcattaggcaccccaggcttTacactttatgcttccggctc
Evidence: [TIM]
Reference(s): [5] Czarniecki D., et al., 1997
[6] Xiong XF., et al., 1991
Terminator(s)
Type: rho-independent
Sequence: gaacttgtagGCCTGATAAGCGCAGCGTATCAGGCaatttttata
Reference(s): [7] Sung YC., et al., 1988
Type: rho-independent
Sequence: gggtcaaagaGGCATGATGCGACGCTTGTTCCTGCGCTTTGTTCATGCCGgatgcggcta
Reference(s): [8] Hediger MA., et al., 1985


Transcription unit       
Name: lacYA
Gene(s): lacA, lacY   Genome Browser M3D Gene expression COLOMBOS
Evidence: [BTEI] Boundaries of transcription experimentally identified
[PAGTSBP] Products of adjacent genes in the same biological process
Reference(s): [27] Zaslaver A., et al., 2006
Promoter
Name: lacYp
+1: Unknown
Note(s): Zaslaver et al. demonstrated in 2006, by means of a library of fluorescent transcription fusions, that this promoter can be transcribed in vitro Zaslaver A,2006. Based on this, a putative promoter was suggested, but the +1 site of the transcription initiation has not been determined, although there exists promoter activity.
Evidence: [IEP]
Reference(s): [27] Zaslaver A., et al., 2006
Terminator(s)
Type: rho-independent
Sequence: gaacttgtagGCCTGATAAGCGCAGCGTATCAGGCaatttttata
Reference(s): [7] Sung YC., et al., 1988
Type: rho-independent
Sequence: gggtcaaagaGGCATGATGCGACGCTTGTTCCTGCGCTTTGTTCATGCCGgatgcggcta
Reference(s): [8] Hediger MA., et al., 1985


RNA cis-regulatory element    
Regulation, transcriptional elongation  
Attenuator type: Translational
Strand: reverse
Evidence: [ICA] Inferred by computational analysis
Reference(s): [28] null null
  Structure type Energy LeftPos RightPos Sequence (RNA-strand)
  terminator -15.8 366315 366351 ggctcgtatgTTGTGTGGAATTGTGAGCGGATAACAATTTCACACAggaaacagct
Notes: "The provided "Sequence" is that of the RNA strand, i.e. U's are shown instead of T's and regulators on the reverse strand will appear as the reverse complement of the sequence delimited by LeftPos-RigtPos"




Reference(s)    

 [1] McCormick JR., Zengel JM., Lindahl L., 1991, Intermediates in the degradation of mRNA from the lactose operon of Escherichia coli., Nucleic Acids Res 19(10):2767-76

 [2] Murakawa GJ., Kwan C., Yamashita J., Nierlich DP., 1991, Transcription and decay of the lac messenger: role of an intergenic terminator., J Bacteriol 173(1):28-36

 [3] Belliveau NM., Barnes SL., Ireland WT., Jones DL., Sweredoski MJ., Moradian A., Hess S., Kinney JB., Phillips R., 2018, Systematic approach for dissecting the molecular mechanisms of transcriptional regulation in bacteria., Proc Natl Acad Sci U S A 115(21):E4796-E4805

 [4] Cannistraro VJ., Kennell D., 1985, The 5' ends of Escherichia coli lac mRNA., J Mol Biol 182(2):241-8

 [5] Czarniecki D., Noel RJ., Reznikoff WS., 1997, The -45 region of the Escherichia coli lac promoter: CAP-dependent and CAP-independent transcription., J Bacteriol 179(2):423-9

 [6] Xiong XF., de la Cruz N., Reznikoff WS., 1991, Downstream deletion analysis of the lac promoter., J Bacteriol 173(15):4570-7

 [7] Sung YC., Fuchs JA., 1988, Characterization of the cyn operon in Escherichia coli K12., J Biol Chem 263(29):14769-75

 [8] Hediger MA., Johnson DF., Nierlich DP., Zabin I., 1985, DNA sequence of the lactose operon: the lacA gene and the transcriptional termination region., Proc Natl Acad Sci U S A 82(19):6414-8

 [9] Flashner Y., Gralla JD., 1988, Dual mechanism of repression at a distance in the lac operon., Proc Natl Acad Sci U S A 85(23):8968-72

 [10] Jimenez CR., Li KW., Smit AB., Janse C., 2005, Auto-inhibitory control of peptidergic molluscan neurons and reproductive senescence., Neurobiol Aging NIL

 [11] Oehler S., Eismann ER., Kramer H., Muller-Hill B., 1990, The three operators of the lac operon cooperate in repression., EMBO J 9(4):973-9

 [12] Shimada T., Ogasawara H., Ishihama A., 2018, Single-target regulators form a minor group of transcription factors in Escherichia coli K-12., Nucleic Acids Res 46(8):3921-3936

 [13] Rimsky S., Spassky A., 1990, Sequence determinants for H1 binding on Escherichia coli lac and gal promoters., Biochemistry 29(15):3765-71

 [14] Spassky A., Rimsky S., Garreau H., Buc H., 1984, H1a, an E. coli DNA-binding protein which accumulates in stationary phase, strongly compacts DNA in vitro., Nucleic Acids Res 12(13):5321-40

 [15] Liu M., Garges S., Adhya S., 2004, lacP1 promoter with an extended -10 motif. Pleiotropic effects of cyclic AMP protein at different steps of transcription initiation., J Biol Chem 279(52):54552-7

 [16] Liu M., Gupte G., Roy S., Bandwar RP., Patel SS., Garges S., 2003, Kinetics of transcription initiation at lacP1. Multiple roles of cyclic AMP receptor protein., J Biol Chem 278(41):39755-61

 [17] Meiklejohn AL., Gralla JD., 1985, Entry of RNA polymerase at the lac promoter., Cell 43(3 Pt 2):769-76

 [18] Merkel TJ., Nelson DM., Brauer CL., Kadner RJ., 1992, Promoter elements required for positive control of transcription of the Escherichia coli uhpT gene., J Bacteriol 174(9):2763-70

 [19] Noel RJ., Reznikoff WS., 1998, CAP, the -45 region, and RNA polymerase: three partners in transcription initiation at lacP1 in Escherichia coli., J Mol Biol 282(3):495-504

 [20] Tutar Y., Harman JG., 2006, Effect of salt bridge on transcription activation of CRP-dependent lactose operon in Escherichia coli., Arch Biochem Biophys 453(2):217-23

 [21] Hoare AM., McLeish A., Thompson H., Alexander-Williams J., 1978, Selection of patients for bile diversion surgery: use of bile acid measurement in fasting gastric aspirates., Gut 19(3):163-5

 [22] Lewis M., 2005, The lac repressor., C R Biol 328(6):521-48

 [23] Rastinejad F., Artz P., Lu P., 1993, Origin of the asymmetrical contact between lac repressor and lac operator DNA., J Mol Biol 233(3):389-99

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 [28] null, null, null, null


RegulonDB