BtGal43B

Ex-Gal0055

(EC. 3.2.1.145) exo-β-1,3-Galactosidase

CAZy Family: GH43

PROPERTIES

1. ELECTROPHORETIC PURITY

-Single band on SDS-gel electrophoresis (MW ~57 kDa)

Figure 1. Electrophoresis analysis of BtGal43B. M, molecular weight marker (PageRuler Prestained Protein Ladder, Thermo Scientific); lane 1, culture lysate of E. coli BL21-pET28a-BtGal43B before IPTG induction; lane 2, culture lysate of E. coli BL21-pET28a-BtGal43B after IPTG induction; lane 3, BtGal43B purified from Ni sepharose fastflow column.

2. SPECIFIC ACTIVITY

0.18 U/mg protein (on pNP-β-gal) at ph7.0 and 37°C.

One Unit of pNP-β-gal activity is defined as the amount of enzyme required to release one μmole of p-nitrophenyl per minute from pNP-β-gal (5 mM) in phosphate buffer (20 mM) pH 7.0.

3. RELATIVE RATES OF HYDROLYSIS OF SUBSTRATES

Table 1. Relative activity of BtGal43B on different substrates.

Figure 2 TLC of BtGal43A hydrolyzed lactose. The concentration of lactose was 2 mg/mL in all reactions. The reactions were incubated in 20 mM sodium phosphate buffer (pH 7.0) for 12 hours.

Figure 3. HPAEC analysis of the activity of BtGal43B. The AGPs were at 5 mg/ml for all reactions. Enzyme concentration was 1 µM. Reactions were incubated for 16 h in 20 mM sodium phosphate buffer pH 7.0 containing 150 mM NaCl buffer.

4. PHYSICOCHEMICAL PROPERTIES

pH Optima: suggested use 7.0

Temperature Optima: suggested use 37 °C

5. STORAGE CONDITIONS

The enzyme should be stored at -20 °C. For assay, this enzyme should be diluted in phosphate buffer (20 mM) pH 7.0. Swirl to mix the enzyme immediately prior to use.

6. REFERENCE

[1] Cartmell A, Muñoz-Muñoz J, Briggs JA, et al. A surface endogalactanase in Bacteroides thetaiotaomicron confers keystone status for arabinogalactan degradation. Nat Microbiol. 2018 Nov;3(11):1314-1326.