2.According to the response of operon to some small molecules with regulatory role Gene regulation include: ■Inducible regulation(可诱导调节)：under some specific metabolites or compound, some genes are turned on,namely that these genes are induced by these substances. For example:lac operon of E.coli. The products of the structural genes of these operon are generally involving in catabolism 20zof carbohydrate 3
2025/5/15 21 ◼ Inducible regulation(可诱导调节): under some specific metabolites or compound, some genes are turned on, namely that these genes are induced by these substances. For example: lac operon of E. coli. The products of the structural genes of these operon are generally involving in catabolism of carbohydrate . 2、According to the response of operon to some small molecules with regulatory role Gene regulation include:
The model of inducible operon Structural gene Regulator gene Operator gene repressor Inducer(诱导 物)： Structural gene be able to induce the bacterium to Regulator gene Operator gene produce the enzymes to catabolize it,the repressor mRNA substance is named as inducer. inducer 0Q00 9Q2八 enzyme 2025/5/15 22
2025/5/15 22 Regulator gene Operator gene Structural gene repressor Regulator gene Operator gene Structural gene repressor inducer mRNA enzyme The model of inducible operon Inducer（诱导 物）： be able to induce the bacterium to produce the enzymes to catabolize it, the substance is named as inducer
Repressible regulation(可阻遏调节)：The genes are generally turned on.Only when some specific metabolites or compound are accumulated,the genes are turned off,namely that these genes are repressed by these substances. For example:trp operon of E.coli. The products of the structural genes of these operon are generally involving in Synthesis of some substances. 2025/5/15 23
2025/5/15 23 ◼ Repressible regulation (可阻遏调节)： The genes are generally turned on. Only when some specific metabolites or compound are accumulated, the genes are turned off, namely that these genes are repressed by these substances. For example: trp operon of E. coli. The products of the structural genes of these operon are generally involving in Synthesis of some substances
The model of repressible operon Structural gene Operator gene Structural gene Regulator gene Regulator gene Operator gene mRMA人个 enzyme Reao eQQe corepressor corepressor(辅阻遏物)： be able to repress the bacterium to produce the enzymes to synthesize it,the substance is named as corepressor
2025/5/15 24 The model of repressible operon Regulator gene Operator gene Structural gene mRNA enzyme Regulator gene Operator gene Structural gene corepressor corepressor （辅阻遏物）： be able to repress the bacterium to produce the enzymes to synthesize it, the substance is named as corepressor
3.Negative transcription regulation include: ： 根据其作用特征又分为负控诱导和负控阻遏 2025/5/15 25
2025/5/15 25 3. Negative transcription regulation include: 根据其作用特征又分为负控诱导和负控阻遏：