Difference between revisions of "Part:BBa K4167660"
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<partinfo>BBa_K4167660 SequenceAndFeatures</partinfo>
 
<partinfo>BBa_K4167660 SequenceAndFeatures</partinfo>
 
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β-galactosidase is encoded by LacZ gene. It is widely found in animals, plants, microorganisms and cultured cells. It can catalyze the hydrolysis of β-galactoside bonds in β-galactoside compounds and release free galactose. It can also cleave lactose to glucose and galactose.  
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BBa_K4167660 is a β-galactosidase protein generator with strong RBS, driven by Plac promoter. This promoter is mainly composed of Lac operon containing LacO site. LacI repressor, encoded by LacI gene, can bind with LacO site to inhibit the binding of RNA pol to the promoter, so the genes downstream expression is blocked. Serving as inducer, IPTG can bind with LacI inhibitor, making it detached from LacO site, which enables the transcription of downstream genes. So, the expression of β-galactosidase is regulated by IPTG induction. With the different concentration of IPTG, it can express β-galactosidase at different level.
 
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β-galactosidase is often used as a reporter protein/enzyme for colorimetric assays. For example, β-galactosidase can cleave X-gal to yield galactose and 5-bromo-4-chloro-3-hydroxyindole. The latter is then oxidized to 5-bromo-4-chloro Indigo, a blue color product which is easily measured.
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β-galactosidase can decompose p-Nitrophenyl-β-D-Galactopyranoside to produce p-Nitrophenol. The product has a characteristic absorption peak at 400 nm. The activity of β-galactosidase can be characterized by the change of absorbance value, which is used to determine the activity of β-galactosidase.
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In addition, β-galactosidase can decompose p-Nitrophenyl-β-D-Galactopyranoside to produce p-Nitrophenol. The product has a characteristic absorption peak at 400 nm. The activity of β-galactosidase can be characterized by the change of absorbance value, which is used to determine the activity of β-galactosidase.
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[[File:K4167660-fig.1.jpg|center]]
 
[[File:K4167660-fig.1.jpg|center]]

Revision as of 20:08, 13 October 2022


LacZ generator driven by Plac

This is a β-galactosidase protein generator with strong RBS, driven by Plac promoter. IPTG can bind to the operator site of the promoter to induce β-galactosidase expression. With the different concentration of IPTG, it can express β-galactosidase at different level. With the detection of p-Nitrophenol, the activity of β-galactosidase can be measured.

Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]


BBa_K4167660 is a β-galactosidase protein generator with strong RBS, driven by Plac promoter. This promoter is mainly composed of Lac operon containing LacO site. LacI repressor, encoded by LacI gene, can bind with LacO site to inhibit the binding of RNA pol to the promoter, so the genes downstream expression is blocked. Serving as inducer, IPTG can bind with LacI inhibitor, making it detached from LacO site, which enables the transcription of downstream genes. So, the expression of β-galactosidase is regulated by IPTG induction. With the different concentration of IPTG, it can express β-galactosidase at different level.
β-galactosidase can decompose p-Nitrophenyl-β-D-Galactopyranoside to produce p-Nitrophenol. The product has a characteristic absorption peak at 400 nm. The activity of β-galactosidase can be characterized by the change of absorbance value, which is used to determine the activity of β-galactosidase.

K4167660-fig.1.jpg