Search results
Results from the WOW.Com Content Network
The lactose operon (lac operon) is an operon required for the transport and metabolism of lactose in E. coli and many other enteric bacteria.Although glucose is the preferred carbon source for most enteric bacteria, the lac operon allows for the effective digestion of lactose when glucose is not available through the activity of β-galactosidase. [1]
Beta-galactoside permease. Galactoside permease is a protein coded by the lacY gene of the lac operon, and is found bound to the membrane of a cell for the purpose of binding galactoside molecules that have been solubilized. The protein is part of a system whose main function is to catalyze the accumulation and transport of lactose and other ...
Galactoside acetyltransferase (also known as Galactoside O-acetyltransferase, thiogalactoside transacetylase, β-galactoside transacetylase and GAT) is an enzyme that transfers an acetyl group from acetyl-CoA to β-galactosides, glucosides and lactosides. It is coded for by the lacA gene of the lac operon in E. coli. [1]
The SOS response is a global response to DNA damage in which the cell cycle is arrested and DNA repair and mutagenesis are induced. The system involves the RecA protein (Rad51 in eukaryotes). The RecA protein, stimulated by single-stranded DNA, is involved in the inactivation of the repressor (LexA) of SOS response genes thereby inducing the ...
Lactose permease is a membrane protein which is a member of the major facilitator superfamily. Lactose permease can be classified as a symporter, which uses the proton gradient towards the cell to transport β-galactosides such as lactose in the same direction into the cell. The protein has twelve transmembrane alpha-helices and its molecular ...
Infobox references. Isopropyl β-d-1-thiogalactopyranoside (IPTG) is a molecular biology reagent. This compound is a molecular mimic of allolactose, a lactose metabolite that triggers transcription of the lac operon, and it is therefore used to induce protein expression where the gene is under the control of the lac operator.
Catabolite Activator Protein (blue) bound to a piece of DNA (red). Catabolite activator protein (CAP; also known as cAMP receptor protein, CRP) is a trans-acting transcriptional activator that exists as a homodimer in solution. Each subunit of CAP is composed of a ligand -binding domain at the N-terminus (CAP N, residues 1–138) and a DNA ...
When referring to a promoter some authors actually mean promoter + operator; i.e., the lac promoter is IPTG inducible, meaning that besides the lac promoter, the lac operon is also present. If the lac operator were not present the IPTG would not have an inducible effect. [citation needed] Another example is the Tac-Promoter system (Ptac ...