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LacI Genetic Sensory Response Unit in Escherichia coli K-12 genome


Gensor Unit Map          
lacZYA_mRNA lacZYA melibiose_Ext coenzyme A arabinosylgalactose LacY beta-D-galactoside glucopyranose melibiose beta-D-galactose LacA lactose acetyl-CoA lactulose_Ext arabinosylgalactose_Ext melibionate_Ext 6-acetyl-beta-D-galactoside LacZ melibionate allolactose lactose_Ext LacI lactulose allolactose arabinose fructofuranose LacI


Gensor Unit       
Name: LacI
Description: Molecular biology level
Detailed: In the absence of lactose LacI negatively regulates the expression of the genes required for transport and catabolism of D-lactose. Under these conditions, LacI binds its targed sites preventing the expression of its regulated genes. In the presence of D-lactose, it is converted to allolactose, LacI is modified to LacI-allolactose, unbinds its target sites, enabling the expression of its regulated genes.
Less detailed: In the absence of lactose LacI negatively regulates the expression of the genes needed for transport and catabolismof D-lactose.

Physiology level
Detailed: The presence of D-lactose induces the expression of genes involved with transport and catabolism of D-lactose. Under these conditions, the genes necessary for transformation of D-lactose to allolactose and D-galactoside to 6-acetyl-b-D-galactoside are expressed.
Less detailed: The presence of D-lactose induces the expression of genes needful for transport and catabolism of D-lactose.
Classification:
Groups: General function prediction only
Inorganic ion transport and metabolism
Carbohydrate transport and metabolism
Gene Ontology Terms (GO): biological_process GO:0005975 - carbohydrate metabolic process
GO:0008643 - carbohydrate transport
GO:0005989 - lactose biosynthetic process
GO:0005990 - lactose catabolic process
GO:0015767 - lactose transport
GO:0008152 - metabolic process
Read more >
cellular_component GO:0009341 - beta-galactosidase complex
GO:0005737 - cytoplasm
GO:0005829 - cytosol
GO:0016021 - integral component of membrane
GO:0005887 - integral component of plasma membrane
GO:0016020 - membrane
GO:0005886 - plasma membrane
Read more >
molecular_function GO:0016407 - acetyltransferase activity
GO:0031420 - alkali metal ion binding
GO:0004565 - beta-galactosidase activity
GO:0030246 - carbohydrate binding
GO:0005351 - carbohydrate:proton symporter activity
GO:0003824 - catalytic activity
GO:0008870 - galactoside O-acetyltransferase activity
Read more >
Components:
  Function Name Type
  simple_molecule 6-acetyl-beta-D-galactoside simple_molecule
  protein LacA protein
  protein LacI protein
  complex LacI-allolactose complex
  protein LacY protein
  protein LacZ protein
  simple_molecule acetyl-CoA simple_molecule
  simple_molecule allolactose simple_molecule
  simple_molecule arabinose simple_molecule
  simple_molecule arabinosylgalactose simple_molecule
  simple_molecule arabinosylgalactose_Ext simple_molecule
  simple_molecule beta-D-galactose simple_molecule
  simple_molecule beta-D-galactoside simple_molecule
  simple_molecule coenzyme A simple_molecule
  simple_molecule fructofuranose simple_molecule
  simple_molecule glucopyranose simple_molecule
  gene lacZYA gene
  RNA lacZYA_mRNA RNA
  simple_molecule lactose simple_molecule
  simple_molecule lactose_Ext simple_molecule
  simple_molecule lactulose simple_molecule
  simple_molecule lactulose_Ext simple_molecule
  simple_molecule melibionate simple_molecule
  simple_molecule melibionate_Ext simple_molecule
  simple_molecule melibiose simple_molecule
  simple_molecule melibiose_Ext simple_molecule


Reactions       
Showing 15 reactions
LacI lacZYA lacZYA_mRNA
Name: lacZYA -> lacZYA_mRNA
Description: Transcription of transcription unit lacZYA. Reaction inhibition by LacI.
Type: transcription
Pathway Components: lacZYA - LacI -> lacZYA_mRNA
Components:
Function Name Type
inhibitor LacI protein
reactant lacZYA gene
product lacZYA_mRNA RNA
allolactose + LacI LacI-allolactose
Name: allolactose + LacI -> LacI-allolactose
Description: Reaction transforming allolactose, LacI into LacI-allolactose
Type: state transition
Pathway Components: allolactose + LacI -> LacI-allolactose
Components:
Function Name Type
reactant LacI protein
product LacI-allolactose complex
reactant allolactose simple_molecule
lacZYA_mRNA LacZ
Name: lacZYA_mRNA -> LacZ
Description: Translation of LacZ
Type: translation
Pathway Components: lacZYA_mRNA -> LacZ
Components:
Function Name Type
product LacZ protein
reactant lacZYA_mRNA RNA
LacZ beta-D-galactose lactose beta-D-galactose + glucopyranose
Name: lactose -> beta-D-galactose + glucopyranose
Description: Reaction transforming lactose into beta-D-galactose, glucopyranose
Type: state transition
Pathway Components: lactose - LacZ - beta-D-galactose -> beta-D-galactose + glucopyranose
Components:
Function Name Type
catalyzer LacZ protein
inhibitor beta-D-galactose simple_molecule
product beta-D-galactose simple_molecule
product glucopyranose simple_molecule
reactant lactose simple_molecule
LacZ lactose allolactose
Name: lactose -> allolactose
Description: Reaction transforming lactose into allolactose
Type: state transition
Pathway Components: lactose - LacZ -> allolactose
Components:
Function Name Type
catalyzer LacZ protein
product allolactose simple_molecule
reactant lactose simple_molecule
LacZ lactulose beta-D-galactose + fructofuranose
Name: lactulose -> beta-D-galactose + fructofuranose
Description: Reaction transforming lactulose into beta-D-galactose, fructofuranose
Type: state transition
Pathway Components: lactulose - LacZ -> beta-D-galactose + fructofuranose
Components:
Function Name Type
catalyzer LacZ protein
product beta-D-galactose simple_molecule
product fructofuranose simple_molecule
reactant lactulose simple_molecule
LacZ arabinosylgalactose beta-D-galactose + arabinose
Name: arabinosylgalactose -> beta-D-galactose + arabinose
Description: Reaction transforming arabinosylgalactose into beta-D-galactose, arabinose
Type: state transition
Pathway Components: arabinosylgalactose - LacZ -> beta-D-galactose + arabinose
Components:
Function Name Type
catalyzer LacZ protein
product arabinose simple_molecule
reactant arabinosylgalactose simple_molecule
product beta-D-galactose simple_molecule
lacZYA_mRNA LacY
Name: lacZYA_mRNA -> LacY
Description: Translation of LacY
Type: translation
Pathway Components: lacZYA_mRNA -> LacY
Components:
Function Name Type
product LacY protein
reactant lacZYA_mRNA RNA
LacY lactose_Ext lactose
Name: lactose_Ext -> lactose
Description: Transport of lactose_Ext through a bacterial membrane, leading to the presence of lactose inside the cell.
Type: transport
Pathway Components: lactose_Ext - LacY -> lactose
Components:
Function Name Type
catalyzer LacY protein
product lactose simple_molecule
reactant lactose_Ext simple_molecule
LacY melibiose_Ext melibiose
Name: melibiose_Ext -> melibiose
Description: Transport of melibiose_Ext through a bacterial membrane, leading to the presence of melibiose inside the cell.
Type: transport
Pathway Components: melibiose_Ext - LacY -> melibiose
Components:
Function Name Type
catalyzer LacY protein
product melibiose simple_molecule
reactant melibiose_Ext simple_molecule
LacY lactulose_Ext lactulose
Name: lactulose_Ext -> lactulose
Description: Transport of lactulose_Ext through a bacterial membrane, leading to the presence of lactulose inside the cell.
Type: transport
Pathway Components: lactulose_Ext - LacY -> lactulose
Components:
Function Name Type
catalyzer LacY protein
product lactulose simple_molecule
reactant lactulose_Ext simple_molecule
LacY arabinosylgalactose_Ext arabinosylgalactose
Name: arabinosylgalactose_Ext -> arabinosylgalactose
Description: Transport of arabinosylgalactose_Ext through a bacterial membrane, leading to the presence of arabinosylgalactose inside the cell.
Type: transport
Pathway Components: arabinosylgalactose_Ext - LacY -> arabinosylgalactose
Components:
Function Name Type
catalyzer LacY protein
product arabinosylgalactose simple_molecule
reactant arabinosylgalactose_Ext simple_molecule
LacY melibionate_Ext melibionate
Name: melibionate_Ext -> melibionate
Description: Transport of melibionate_Ext through a bacterial membrane, leading to the presence of melibionate inside the cell.
Type: transport
Pathway Components: melibionate_Ext - LacY -> melibionate
Components:
Function Name Type
catalyzer LacY protein
product melibionate simple_molecule
reactant melibionate_Ext simple_molecule
lacZYA_mRNA LacA
Name: lacZYA_mRNA -> LacA
Description: Translation of LacA
Type: translation
Pathway Components: lacZYA_mRNA -> LacA
Components:
Function Name Type
product LacA protein
reactant lacZYA_mRNA RNA
LacA coenzyme A beta-D-galactoside + acetyl-CoA 6-acetyl-beta-D-galactoside + coenzyme A
Name: beta-D-galactoside + acetyl-CoA -> 6-acetyl-beta-D-galactoside + coenzyme A
Description: Reaction transforming beta-D-galactoside, acetyl-CoA into 6-acetyl-beta-D-galactoside, coenzyme A
Type: state transition
Pathway Components: beta-D-galactoside + acetyl-CoA - LacA - coenzyme A -> 6-acetyl-beta-D-galactoside + coenzyme A
Components:
Function Name Type
product 6-acetyl-beta-D-galactoside simple_molecule
catalyzer LacA protein
reactant acetyl-CoA simple_molecule
reactant beta-D-galactoside simple_molecule
inhibitor coenzyme A simple_molecule
product coenzyme A simple_molecule



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