SaAra27A

Ex-Ara0141

(EC.3.2.1)exo-β-Arabinopyranoside

CAZy Family: GH27

PROPERTIES

1.ELECTROPHORETIC PURITY

-Single band on SDS-gel electrophoresis (MW ~64 kDa)

Figure 1. Electrophoresis analysis ofSaAra27A. M, molecular weight marker (PageRuler Prestained Protein Ladder, Thermo Scientific); lane 1, culture lysate before IPTG induction; lane 2, culture lysate after IPTG induction; lane 3, SaAra27A purified from Ni sepharose fastflow column.

2.SPECIFIC ACTIVITY

21.0 U/mg protein (on pNP-β-Arap) at pH4.0 and 40^oC.

One Unit of pNP-β-Arapactivity is defined as the amount of enzyme required to release 1 μmol of p-nitrophenyl per minute from pNP-β-Arap (2mM) in 0.1 M Na₂HPO₄and 0.05 M citric acid, pH 4.0.

3.RELATIVE RATES OF HYDROLYSIS OF SUBSTRATES

Table 1. Relative activity of SaAra27A on different substrates^a.

^aReactions were performed with 2 mM substrate, pH 4.0, at 40°C for 10 min.

^bAbsorption caused by released p-nitrophenol was measured at 405 nm. The relative activity on pNPβArap was taken as 100%.

^cThe data are reported as means±standard errors from the mean for three independent experiments.

Table 2.Substrate specificity ofSaAra27Atoward polysaccharides.

4.PHYSICOCHEMICAL PROPERTIES

pH Optima: 4.0

Temperature Optima: 40°C

5.STORAGE CONDITIONS

The enzyme should be stored at -20°C. For assay, this enzyme should be diluted in sodiumacetate(20 mM) pH4.0. Swirl to mix the enzyme immediately prior to use.

6. REFERENCES

[1] Ichinose H, Fujimoto Z, Honda M, et al. A β-l-arabinopyranosidase from Streptomyces avermitilis is a novel member of glycoside hydrolase family 27[J]. Journal of Biological Chemistry, 2009, 284(37): 25097-25106