Based on the above considerations

Based on the above considerations, the β-galactosidase gene from Exiguobacterium acetylicum MF03 (not previously reported) was cloned, expressed and purified with the aim of assessing the potential of this novel enzyme for catalyzing reactions of synthesis and hydrolysis of glycosides. Because of E. acetylicum MF03 was isolated from the Maule lagoon, Chile (Figueroa et al., 2018), a lake-filled volcanic caldera in central Chile near the border to Argentina, it was expected this β-galactosidase from E. acetylicum MF03 having unique features with respect to the already described β-galactosidases.
Materials and methods
Results and discussion
Conclusions β-galEa was successfully sequenced, cloned, heterologously expressed, purified and kinetically characterized. Like other β-galactosidases from the GH-42 family, β-galEa was unable to catalyze the hydrolysis or transgalactosylation of lactose. However, it was able to catalyze both reactions from lactulose. Hence, β-galEa has an exquisite substrate specificity, which may be used for technological purposes, for example, in the fabrication of an enzymatic kit for the quantification of lactulose in thermally treated milk. Furthermore, this enzyme has other technologically attractive features: no metal cofactors are required, specific activity is high, optimum pH is slightly acidic, thermal stability is good and inhibition by galactose is moderate.
Acknowledgement
The organic matter and nitrogen availability in soil are crucial for maintaining soil quality and agricultural productivity. Substantial research is being conducted to identify the link between soil organic matter and soil structural stability for improving soil strength and reducing soil erosion . Additionally, soil microbes are known to play crucial roles in the functioning of ecosystems by cycling nutrients, degrading organic matter and pollutants, and improving soil fertility and crop health . Numerous studies have been performed to determine how soil microbial Temozolomide can be affected and changed with soil management , , . Therefore, considerable research is directed toward the soil microbial community and diversity assessment using culture-independent approaches. Nevertheless, few studies have been devoted to exploring the genetic diversity and gene function of the soil ecosystem through metagenomic analysis. Recently, forest soil–derived lignocellulolytic microbial consortia revealed that an overrepresentation of predicted carbohydrate transporters (ATP-binding cassette, TonB-dependent transporter, and phosphotransferases), two-component sensing systems, and β-glucosidases/galactosidases can be observed in soil in which wheat straw was cultivated . Moreover, in soil with crop succession or rotation, hydrolases including lipases, laccases, cellulases, proteases, amylases, and pectinases were abundantly identified . In the Carbohydrate-Active Enzyme Database (CAZy), the GH family is involved in the hydrolysis of various carbohydrates . Several natural forms of biomass, including cellulose, hemicellulose, starch, and other polysaccharides, can be catalyzed with glycoside hydrolases (GHs), such as cellulase, amylase, and galactosidase . Among these, α-galactosidases (α--galactoside galactohydrolases; EC 3.2.1.22), or melibiases, are involved in the hydrolysis of α-1,6-linked galactoside moieties from different oligosaccharides such as raffinose, stachyose, and melibiose as well as the guar gum and locust bean gum of polysaccharides . They widely exist in prokaryotes, eukaryotes, and archaea and have potential applications in the medical, food, and environmental fields for treating Fabry disease, improving the nutritive value of animal feeds, and enhancing pulp bleaching, respectively . In the CAZy database, α-galactosidases are present in GH 4, 27, 36, 57, 97, and 110 families as distinguished by conserved amino acid sequences . Prokaryotic α-galactosidases are extensively found in all these farmilies, whereas eukaryotic α-galactosidases are found in GH 27 and 36 families. In addition, several 3D structures of α-galactosidases from humans, rice, yeasts, filamentous fungi, and bacteria were examined based on the Protein Data Bank database.