β-galactosidase is an enzyme which catalyses the hydrolysis of terminal non-reducing β-D-galactose residues in β-D-galactosides by cleaving a β-glycosidic bond. Assay of β-galactosidase activity can be used for the rapid detection of lactose-fermenting coliform bacteria, including E. coli. In molecular biology, measurement of the levels of active β-galactosidase may be used to monitor the success of gene transfer where the lacZ gene, the gene for β-galactosidase, is used as a reporter gene.
| Enzyme | Substrate | Product Code | MSDS |
| β-galactosidase | MNP-Gal | 1053 | MNP-Gal |
| VQM-Gal | 1054 | VQM-Gal | |
| VBzTM-Gal | 1056 | VBzTM-Gal | |
| VLE-Gal | 1071 | VLE-Gal | |
| VLPa-Gal | 1072 | VLPa-Gal | |
| VLPr-Gal | 1073 | VLPr-Gal | |
| VQE-Gal | 1074 | VQE-Gal |
Available in 1g, 0.5g, 0.1g quantities. Details of other quantities available on request.
References: Bainbridge et al (1991) Improved method for the detection of β-galactosidase activity in colonies of E. coli using a new chromogenic substrate. FEMS Micobiol Lett. 80, 319-324. Posci et al (1993) Comparison of several new galactosidase as substrates for various β-D-galactosidases. Biochim Biophys Acta, 1163, 54-60.
1053 MNP-Gal powder
This substrate is a pale yellow powder. Hydrolysis of this substrate by β-galactosidase releases a product that is red in colour at pH> 9.5 and can be measured at 505 nm. Extinction coefficient of the released product is 27,000 Lmol-1cm-1.
3-Methoxy-4-(2-nitrovinyl)-phenyl-β-D-galactopyranoside: C15H20NO9
Molecular weight: 357 gmol-1 CAS number: 70622-78-5
1054 VQM-Gal powder
This substrate is an orange yellow powder. Hydrolysis of this substrate by β-galactosidase releases a product that is red in colour at pH> 9.5 and can be measured at 515 nm. Extinction coefficient of the released product is 42,500 Lmol-1cm-1.
2-{2-[(4-(β-D-galactopyranosyloxy)-3-methoxyphenyl]-vinyl}-1-methylquinolinium iodide: C25H28NO7.I
Molecular weight: 581 gmol-1
1056 VBzTM-Gal powder
This substrate is an orange yellow powder. Hydrolysis of this substrate by β-galactosidase releases a product that is red in colour at pH> 9.5 and can be measured at 519 nm. Extinction coefficient of the released product is 55,000 Lmol-1cm-1.
2-{2-[4-(β-D-galactopyranosyloxy)-3-methoxyphenyl]-venyl}-3-methylbenzothiazolium iodide: C23H26NO7S.I
Molecular weight: 587 gmol-1
1071 VLE-Gal powder
This substrate is an orange yellow powder. Hydrolysis of this substrate by β-galactosidase releases a product that is violet in colour at pH> 9.5 and can be measured at 540 nm. Extinction coefficient of the released product is 33,800 Lmol-1cm-1.
(E)-1-ethyl-4-(3-methoxy-4-(3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yloxy)syryl)quinolinium: C26H30NO7
Molecular weight: 468 gmol-1
1072 VLPa-Gal powder
This substrate is an orange powder. Hydrolysis of this substrate by β-galactosidase releases a product that is magenta in colour at pH> 9.5 and can be measured at 525 nm. Extinction coefficient of the released product is 35,000 Lmol-1cm-1.
Ammonioum-4-{2-[(4-(β-D-galactopyranosyloxy)-3-methoxyphenyl]-vinyl}-1-(propan-3-yl-carboxylate)-quinolinium: C27H30NO9.Br
Molecular weight: 592 gmol-1
1073 VLPr-Gal powder
This substrate is an orange yellow powder. Hydrolysis of this substrate by β-galactosidase releases a product that is violet in colour at pH> 9.5 and can be measured at 555 nm. Extinction coefficient of the released product is 33,800 Lmol-1cm-1.
((E)-4-(3-methoxy-4-(3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yloxy)styryl)-1-propylquinolinium iodide: C27H32NO7.I
Molecular weight: 609 gmol-1
1074 VQE-Gal powder
This substrate is an orange powder. Hydrolysis of this substrate by β-galactosidase releases a product that is magenta in colour at pH> 9.5 and can be measured at 515 nm. Extinction coefficient of the released product is 48,000 Lmol-1cm-1.
1-ethyl-2-(3-methoxy-4-((4R,5R))-3,4,5-trihydroxy-6-(hydroxymethyl)tetrahrdo-2H-pyran-2-yloxy)styryl)quinolinium iodide: C26H30O7N.I
Molecular weight: 595 gmol-1