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Judy Ventura/Sandbox1
From Proteopedia
A CBI Molecule being studied in the University of Massachusetts Amherst Chemistry-Biology Interface Program at UMass Amherst and on display at the Molecular Playground.
β-Galactosidase is a hydrolase enzyme that catalyzes the hydrolysis of beta- galactosidase into monosaccharides (carbon/energy source). Is encoded by the lacZ gene of the lac operon in E.coli. It is a large 120 kDa, >1000 amino acids) protein that forms a tetramer.
It is commonly used as a reporter molecule in genetics and molecular biology. Usually, experiments are designed so that the β-Galactosidase concentration in the cell is a readout for some aspect of a system being studied. When the β-Galactosidase cleaves the substrate o-nitrophenyl-b-D-galactopyraniside (ONPG), o-nitrophenol is released. This compound has a yellow color, and absorbs 420 nm light. To measure β-Galactosidase activity the accumulation of yellow color (increase 420 nm absorbance)/minute is monitored.
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| 3iap, resolution 2.00Å () | |||||||||
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| Ligands: | , , , | ||||||||
| Gene: | lacZ (Escherichia coli K-12) | ||||||||
| Activity: | Beta-galactosidase, with EC number 3.2.1.23 | ||||||||
| Related: | 1dp0, 3dym, 3iaq | ||||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
