Hydrolyzes o-nitrophenyl-beta-D-galactopyranoside (ONPG), p-nitrophenyl-beta-D-galactopyranoside (PNPG), 5-bromo-4-chloro-3-indoyl-beta-D-galactosde (X-gal), o-nitrophenyl-beta-D-fucopyranoside (ONPF) and p-nitrophenyl-beta-D-fucopyranoside (PNPF) with greatest activity towards ONPG and PNPG and low levels of activity with ONPF and PNPF. Detectable, but very low levels of activity towards p-nitrophenyl-beta-lactose (PNPL), p-nitrophenyl-beta-cellobiose (PNPC), p-nitrophenyl-alpha-galactopyranoside (PNP-alpha-G), and p-nitrophenyl-beta-xylopyranoside (PNPX). Hydrolysis of terminal non-reducing beta-D-galactose residues in beta-D-galactosides. No activity is lost during treatment with 20 or 100 mM EDTA in Z buffer for 3 hours at 0 degrees Celsius, nor is activity greatly stimulated by the addition of cations. Inhibited by 1 mM zinc and 1 mM copper, the levels of activity decrease to 10% of the untreated control. Nickel, cobalt and manganese at concentrations of 10 mM decrease enzyme activity to either 40% (for nickel and cobalt) or 60% (for manganese) of the activity in untreated controls. No change in enzyme activity in the presence of calcium and magnesium at concentrations up to 50 mM. EDTA-treated enzyme exhibits a slight increase in relative specific activity when it is assayed in the presence of 50 mM NaCl or 50 mM KCl, it does not exhibit enhanced activity at concentrations greater than 250 mM. Maintains between 20 and 40% of activity in the presence of 4 M NaCl or 4 M KCl, and it is more active in the presence of KCl than in the presence of NaCl. Retains 50% of activity in the presence of 3 M KCl or 2.5 M NaCl. Optimum pH is 6.5. Optimum temperature is 42 degrees Celsius. Thermostable at temperatures at or below the optimal temperature for activity, but it is rapidly denatured at temperatures above 42 degrees Celsius. Irreversibly inactivated within 10 minutes at 55 degrees Celsius. Stable during storage at 5 degrees Celsius and loses no activity during storage for 4 months. Retains 10% of activity at 0 degrees Celsius. Dimer. Possible reporter enzyme for halotolerant and halophilic organisms. May also be used in the food industry to digest plant polysaccharides in high-salt processes. Belongs to the glycosyl hydrolase 42 family.