Heterologous expression and biochemical characterization of a novel cold-active α-amylase from the Antarctic bacteria Pseudoalteromonas sp. 2-3

Molting Alters the Microbiome, Immune Response, and Digestive Enzyme Activity in Mud Crab ( Scylla paramamosain )

“…The bacterial genera Bacteroides , Clostridium , and Pseudoalteromonas are significantly correlated with amylase activity in the midgut of mud crabs during molting ( Fig. 7C ), which is consistent with the results of previous studies that many members of these genera can produce amylase ( 65 – 67 ). Collectively, the results of this study suggest that digestive enzymes could regulate the microbiota in the hepatopancreas and midgut of mud crab during molting, which provides a suitable condition for the restoration and reconstruction of host-microbiome homeostasis in crab molting.…”

Revisiting the scope and applications of food enzymes from extremophiles

“…Recently, a cold‐active α‐amylase was expressed from Pseudoalteromona sp., a bacterium isolated from the Chilean Antarctic seawater. The pH optimum of this enzyme was 8.0, while the optima temperature was 20°C (Sanchez, Ravanal, Andrews, & Asenjo, 2019). The low optimum temperature reported for this enzyme makes it an excellent alternative in the food industry where low‐temperature processes are required, thus, minimizing cost.…”

Recapitulation of stability diversity of microbial α-amylases

“…The heterologous expression of α-amylase from Antarctic bacterium Pseudoalteromonas sp. 2-3 in E. coli BL21 (DE3) showed the optimum temperature at 20 °C with activation by Ca 2+ , the enzyme being active on potato starch giving a K m of 6.94 mg/mL and V max of 0.27 mg/mL.min [84]. Kim et al [85] in 2017 boosted the stability of psychrophilic α-amylase by cloning the gene encoding an α-amylase from a psychrophilic Arthrobacter agilis PAMC 27388 strain into a pET-28a (+) vector and this was heterologously expressed in E. coli BL21 (DE3).…”

“…A classic example for this is represented by the cold adapted α-amylase, Amy13c6 from a metagenomic library of the cold and alkaline environment of Greenland. This enzyme had an optimal pH of 8.0-9.0, so that it can be used in laundry applications at very low temperatures [84]. The α-amylase gene (amyM) derived using the pUC19 vector from soil metagenomic library when overexpressed and purified was stable at pH 9.0 [54].…”