title: Cloning and Characterization of Cold-Adapted α-Amylase from Antarctic Arthrobacter agilis.
abstract: In this study, the gene encoding an α-amylase from a psychrophilic Arthrobacter agilis PAMC 27388 strain was cloned into a pET-28a(+) vector and heterologously expressed in Escherichia coli BL21(DE3). The recombinant α-amylase with a molecular mass of about 80 kDa was purified by using Ni2+-NTA affinity chromatography. This recombinant α-amylase exhibited optimal activity at pH 3.0 and 30 °C and was highly stable at varying temperatures (30-60 °C) and within the pH range of 4.0-8.0. Furthermore, α-amylase activity was enhanced in the presence of FeCl3(1 mM) and β-mercaptoethanol (5 mM), while CoCl2(1 mM), ammonium persulfate (5 mM), SDS (10 %), Triton X-100 (10 %), and urea (1 %) inhibited the enzymatic activity. Importantly, the presence of Ca2+ions and phenylmethylsulfonyl fluoride (PMSF) did not affect enzymatic activity. Thin layer chromatography (TLC) analysis showed that recombinant A. agilis α-amylase hydrolyzed starch, maltotetraose, and maltotriose, producing maltose as the major end product. These results make recombinant A. agilis α-amylase an attractive potential candidate for industrial applications in the textile, paper, detergent, and pharmaceutical industries.
authors.affiliation: Department of Biotechnology and Bioengineering, Interdisciplinary Program for Bioenergy and Biomaterials, Chonnam National University, Gwangju, 61186, South Korea.
authors.forename: Su-Mi
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Korea Polar Research Institute, Incheon, 21990, South Korea.
authors.forename: Hyun
authors.initials: H
authors.lastname: Park
authors.affiliation: Department of Biotechnology and Bioengineering, Interdisciplinary Program for Bioenergy and Biomaterials, Chonnam National University, Gwangju, 61186, South Korea. choiji01@jnu.ac.kr.
authors.forename: Jong-Il
authors.initials: JI
authors.lastname: Choi
mesh_terms: D001173:Arthrobacter / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D003080:Cold Temperature; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D013213:Starch / Q000737:chemistry*; D000516:alpha-Amylases / Q000737:chemistry* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins; D013213:Starch; D000516:alpha-Amylases
keywords: Arthrobacter agilis; Cloning; Cold-adapted α-amylase; Expression