Part:BBa_K1444017
Full length beta-galactosidase (LacZ)
Beta-galactosidase (EC 3.2.1.23), or LacZ, is a classic enzyme most commonly used in blue-white colony screening when used in specialized vectors. This part consists of the full length beta-galactosidase sequence which can be inserted downstream of a promoter to produce the tetrameric, 47.4kDa enzyme. This part was amplified from a well-used expression vector from a molecular biology lab, and cloned into the BioBrick vector pSB1C3.
Usage and Biology
Beta-galactosidase cleaves the beta-glycosidic bond of a galactose bound to an organic moiety; the physiological function is to break down beta-galactosides, such as lactose, into it's respective monnosaccharides. Beta-galactosidase can act as a reporter when provided substrates such as [http://en.wikipedia.org/wiki/X-gal X-gal]. The cleavage of X-gal releases galactose and the chromophoric, substituted indole moiety. The most common form of X-gal is 5-Bromo-3-indolyl β-D-galactopyranoside, which produces an intense blue pigment. Other versions of X-gal may be used to produce other color pigments.
Typically 40-60uL of a 20ug/mL X-gal solution, dissolved in dimethyl sulfoxide or dimethyl formamide, is spread on a plate and allowed to dry before plating the bacteria expressing beta-galactosidase. X-gal may also be added to liquid cultures or incorporated into solid agar media.
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25COMPATIBLE WITH RFC[25]
- 1000COMPATIBLE WITH RFC[1000]
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