The lactose (lac) operon is a prototypical gene regulatory system. This thesis describes a three-dimensional, agent-based, visual computer model of the lac operon. The reader is provided with relevant background knowledge from the fields of molecular biology, agent-based systems, and computer ...
Mutations that define the Lac-Operon model: Jacob and Monod found mutants that did not show the normal regulation, that is, synthesis of Z, Y, and A proteins only when lactose was present. Two kinds of mutants gave constitutive (continuous) synthesis of β-galactosidase, permease and ...
Draw diagrams of the lac operon (乳糖操纵子)that illustrate (图解)(1) negative control(负调控)(2) positive control(正调控)(1 )负调控是指调节基因产物repressor的调控,repressor有活性时阻遏了 lac Z Y A的⏺表达。当环境中无乳糖时:I基因产生的蛋白质即阻遏物同操纵基因0结合,阻止了RNA多聚酶的向...
This paper presents an activity that engages students in model-based reasoning, requiring them to predict the behavior of thetrpandlacoperons under different environmental conditions. Students are presented six scenarios for thetrpoperon and five for thelacoperon. In most of the scenarios, specific ...
The lactose operon (lacTEGF) from Lactobacillus casei strain BL23 has been previously studied. The lacT gene codes for a transcriptional antiterminator, lacE and lacF for the lactose-specific phosphoenolpyruvate: phosphotransferase system (PTSLac) EIICB
Another factor that may cause deviations from a linear trend is an increased gene-expression heterogeneity between cells in the absence of IPTG, a well-known property of the lac operon whose constituent parts we have used in our genetic constructs [47], which might confer heterogeneous growth ...
Apparent directed mutability, its recombination requirement, and its apparent independence of cell growth are all accounted for by the model. Evidence is provided for the required residual function and gene amplification. 展开 关键词: Gene Amplification Lac Operon Mutagenesis Salmonella typhimurium beta-...
Genetically structured models forlac promoter–operator function in the Escherichia coli chromosome and in multicopy plasmids: Lac operator function A mathematical model based on known molecular interactions has been formulated to describe quantitatively regulation of expression of the lactose (lac) ope......
The metabolic circuit was assembled on plasmid pUC18 with Ldh* and Mae* coexpression controlled under the lac operon, and transformed into BW25113 (△ldhA, dld::cat) and XYC5016, namely BW25113 (ΔldhA, Δdld, arsB::Para-FtNadE-c-his-NcdS-2-CtCTPS*), to give strain XYD046 and ...
tuberculosis ICL gene was used due to the availability of the lac operon for inducible expression of the ICL protein. Site directed mutagenesis of the ICL was done to introduce point mutations at Asp108Ala and Cys191Ser. A total of 6 colonies from both mutated ICL plates were randomly picked...