RegulonDB RegulonDB 10.8: Operon Form
   

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




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


Transcription unit          
Name: mtr
Gene(s): mtr   Genome Browser M3D Gene expression COLOMBOS
Note(s): The expression of the mtr gene is activated by TyrR and repressed by TrpR, HU, and IHF. The negative effects of HU and IHF seem to be relieved by the positive effect of TyrR Yang J,1996
In the presence of tyrosine and ATP, the TyrR protein is bound to two tyrR boxes, a strong one and a weak one, located at -76.5 and -106.5 bp upstream of the mtrp promoter, respectively. At these positions, the mtr gene expression is fully activated by TyrR Sarsero JP,1991
In the presence of phenylalanine or in the absence of an effector, the TyrR protein bound to the strong TryR box partially activates the transcription. When the TrpR protein is absent, tryptophan can also activate the transcription of mtr Sarsero JP,1991
During the transcription activation of mtr, there may be an interaction between the TyrR protein and the α-CTD of the RNA polymerase. The residues leucine-262, arginine-265, and lysine-298 are mainly involved in this interaction. When TyrR is absent, the α-CTD seems to interact with the UP element centered at -41 from the transcriptional start site of the mtrp promoter to activate the transcription Yang J,1997
TrpR plus tryptophan can repress the expression of mtr; however, when the TrpR protein is absent, tryptophan can also activate the transcription Sarsero JP,1991
When tryptophan is present, the TrpR protein binds to two sites overlapping the mtrp2 promoter. Therefore, TrpR could block the binding of the RNA polymerase to the promoter. With high tryptophan levels, the repression is dominant over the activation; with low tryptophan levels, activation and repression can interact to regulate the mtr gene expression Sarsero JP,1991
Evidence: [BTEI] Boundaries of transcription experimentally identified
Reference(s): [1] Heatwole VM., et al., 1991
[2] Sarsero JP., et al., 1991
Promoter
Name: mtrp2
+1: 3305860
Sigma Factor: Sigma70 Sigmulon
Distance from start of the gene: 43
Sequence: tttttaccatcggggctttttttctgtcttttgtactcgtgtactggtacagtgcaatgcAtaacaacgcagtcgcactat
                     -35                        -10         +1                   
Evidence: [CV(RS-EPT-CBR)]
[CV(TIM)]
[HIPP]
[RS-EPT-CBR]
[TIM]
Reference(s): [1] Heatwole VM., et al., 1991
[3] Salgado H, et al., 2012
[2] Sarsero JP., et al., 1991
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
nd HU repressor mtrp2 nd nd nd nd nd [GEA] [7]
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence (Confirmed, Strong, Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
nd IHF repressor mtrp2 nd nd nd nd nd [GEA] [7]
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence (Confirmed, Strong, Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
proximal TrpR-tryptophan repressor mtrp2 3305863 3305880 -11.5 ttgtactcgtGTACTGGTACAGTGCAATgcataacaac nd [APIORCISFBSCS], [BPP], [CV(GEA)], [CV(GEA)], [GEA] [1], [2], [6]
proximal TrpR-tryptophan repressor mtrp2 3305871 3305888 -19.5 tctgtcttttGTACTCGTGTACTGGTACagtgcaatgc nd [APIORCISFBSCS], [BPP], [CV(GEA)], [CV(GEA)], [GEA] [1], [2], [6]
Type Transcription factor Function Promoter Binding Sites Growth Conditions Evidence (Confirmed, Strong, Weak) Reference(s)
LeftPos RightPos Central Rel-Pos Sequence
proximal TyrR-tyrosine activator mtrp2 3305928 3305945 -76.5 gaacacaatcTGTAAAATAATATATACAgccccgattt nd [APIORCISFBSCS], [BPP], [CV(GEA)], [CV(GEA)], [CV(GEA/SM)], [CV(SM)], [GEA], [SM] [1], [2], [4], [5]
remote TyrR-tyrosine activator mtrp2 3305958 3305975 -106.5 ggtggtgatgCGTAATCATCGCTGAACAgcgaacacaa nd [APIORCISFBSCS], [BPP], [CV(GEA)], [CV(GEA)], [CV(GEA/SM)], [CV(SM)], [GEA], [SM] [1], [4], [5]


Transcription unit       
Name: mtr
Gene(s): mtr   Genome Browser M3D Gene expression COLOMBOS
Evidence: [BTEI] Boundaries of transcription experimentally identified
Reference(s): [1] Heatwole VM., et al., 1991
Promoter
Name: mtrp1
+1: 3305932
Distance from start of the gene: 115
Sequence: tcgtttcggtggtgatgcgtaatcatcgctgaacagcgaacacaatctgtaaaataatatAtacagccccgatttttacca
Note(s): It is not known under what conditions the mtrp1 promoter is active Heatwole VM,1991
Evidence: [TIM]
Reference(s): [1] Heatwole VM., et al., 1991


RNA cis-regulatory element    
Regulation, transcriptional elongation  
Attenuator type: Transcriptional
Strand: reverse
  Structure type Energy LeftPos RightPos Sequence (RNA-strand)
  terminator -8.8 3305835 3305870 gtactggtacAGTGCAATGCATAACAACGCAGTCGCACTATTTTTcactggagag
  anti-terminator -8.72 3305861 3305906 taccatcgggGCTTTTTTTCTGTCTTTTGTACTCGTGTACTGGTACAGTGCAATGcataacaacg
  anti-anti-terminator -15.0 3305904 3305928 taatatatacAGCCCCGATTTTTACCATCGGGGCtttttttctg
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] Heatwole VM., Somerville RL., 1991, The tryptophan-specific permease gene, mtr, is differentially regulated by the tryptophan and tyrosine repressors in Escherichia coli K-12., J Bacteriol 173(11):3601-4

 [2] Sarsero JP., Wookey PJ., Pittard AJ., 1991, Regulation of expression of the Escherichia coli K-12 mtr gene by TyrR protein and Trp repressor., J Bacteriol 173(13):4133-43

 [3] Salgado H, Peralta-Gil M, Gama-Castro S, Santos-Zavaleta A, Muñiz-Rascado L, García-Sotelo JS, Weiss V, Solano-Lira H, Martínez-Flores I, Medina-Rivera A, Salgado-Osorio G, Alquicira-Hernández S, Alquicira-Hernández K, López-Fuentes A, Porrón-Sotelo L, Huerta AM, Bonavides-Martínez C, Balderas-Martínez YI, Pannier L, Olvera M, Labastida A, Jiménez-Jacinto V, Vega-Alvarado L, Del Moral-Chávez V, Hernández-Alvarez A, Morett E, Collado-Vides J., 2012, RegulonDB v8.0: omics data sets, evolutionary conservation, regulatory phrases, cross-validated gold standards and more., Nucleic Acids Res.

 [4] Sarsero JP., Pittard AJ., 1991, Molecular analysis of the TyrR protein-mediated activation of mtr gene expression in Escherichia coli K-12., J Bacteriol 173(23):7701-4

 [5] Yang J., Murakami K., Camakaris H., Fujita N., Ishihama A., Pittard AJ., 1997, Amino acid residues in the alpha-subunit C-terminal domain of Escherichia coli RNA polymerase involved in activation of transcription from the mtr promoter., J Bacteriol 179(19):6187-91

 [6] Jeeves M., Evans PD., Parslow RA., Jaseja M., Hyde EI., 1999, Studies of the Escherichia coli Trp repressor binding to its five operators and to variant operator sequences., Eur J Biochem 265(3):919-28

 [7] Yang J., Camakaris H., Pittard AJ., 1996, In vitro transcriptional analysis of TyrR-mediated activation of the mtr and tyrP+3 promoters of Escherichia coli., J Bacteriol 178(21):6389-93


RegulonDB