title: Characterization of a Novel Maltose-Forming α-Amylase from Lactobacillus plantarum subsp. plantarum ST-III.
abstract: A novel maltose (G2)-forming α-amylase from Lactobacillus plantarum subsp. plantarum ST-III was expressed in Escherichia coli and characterized. Analysis of conserved amino acid sequence alignments showed that L. plantarum maltose-producing α-amylase (LpMA) belongs to glycoside hydrolase family 13. The recombinant enzyme (LpMA) was a novel G2-producing α-amylase. The properties of purified LpMA were investigated following enzyme purification. LpMA exhibited optimal activity at 30 °C and pH 3.0. It produced only G2 from the hydrolysis of various substrates, including maltotriose (G3), maltopentaose (G5), maltosyl β-cyclodextrin (G2-β-CD), amylose, amylopectin, and starch. However, LpMA was unable to hydrolyze cyclodextrins. Reaction pattern analysis using 4-nitrophenyl-α-d-maltopentaoside (pNPG5) demonstrated that LpMA hydrolyzed pNPG5 from the nonreducing end, indicating that LpMA is an exotype α-amylase. Kinetic analysis revealed that LpMA had the highest catalytic efficiency (kcat/Km ratio) toward G2-β-CD. Compared with β-amylase, a well-known G2-producing enzyme, LpMA produced G2 more efficiently from liquefied corn starch due to its ability to hydrolyze G3.
authors.affiliation: Department of Food Science and Nutrition, and Center for Aging and Health Care, Hallym University , Hallymdaehak-gil 1, Chuncheon, Gwangwon-do 200-702, Korea.
authors.forename: Hye-Yeon
authors.initials: HY
authors.lastname: Jeon
authors.affiliation: Department of Food Science and Nutrition, and Center for Aging and Health Care, Hallym University , Hallymdaehak-gil 1, Chuncheon, Gwangwon-do 200-702, Korea.
authors.forename: Na-Ri
authors.initials: NR
authors.lastname: Kim
authors.affiliation: Department of Food Science and Nutrition, and Center for Aging and Health Care, Hallym University , Hallymdaehak-gil 1, Chuncheon, Gwangwon-do 200-702, Korea.
authors.forename: Hye-Won
authors.initials: HW
authors.lastname: Lee
authors.affiliation: Department of Food Science and Nutrition, and Center for Aging and Health Care, Hallym University , Hallymdaehak-gil 1, Chuncheon, Gwangwon-do 200-702, Korea.
authors.forename: Hye-Jeong
authors.initials: HJ
authors.lastname: Choi
authors.affiliation: Department of Food Science and Nutrition, and Center for Aging and Health Care, Hallym University , Hallymdaehak-gil 1, Chuncheon, Gwangwon-do 200-702, Korea.
authors.forename: Woo-Jae
authors.initials: WJ
authors.lastname: Choung
authors.affiliation: Department of Food Science and Nutrition, and Center for Aging and Health Care, Hallym University , Hallymdaehak-gil 1, Chuncheon, Gwangwon-do 200-702, Korea.
authors.forename: Ye-Seul
authors.initials: YS
authors.lastname: Koo
authors.affiliation: Department of Food Science and Nutrition, and Center for Aging and Health Care, Hallym University , Hallymdaehak-gil 1, Chuncheon, Gwangwon-do 200-702, Korea.
authors.forename: Dam-Seul
authors.initials: DS
authors.lastname: Ko
authors.affiliation: Department of Food Science and Nutrition, and Center for Aging and Health Care, Hallym University , Hallymdaehak-gil 1, Chuncheon, Gwangwon-do 200-702, Korea.
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Shim
mesh_terms: D003505:Cyclodextrins / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D006868:Hydrolysis; D007700:Kinetics; D048191:Lactiplantibacillus plantarum / Q000201:enzymology*; D008320:Maltose / Q000031:analogs & derivatives / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D013379:Substrate Specificity; D014312:Trisaccharides / Q000378:metabolism; D000516:alpha-Amylases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D003505:Cyclodextrins; D011994:Recombinant Proteins; D014312:Trisaccharides; C433303:maltosyl-cyclodextrin; C008317:maltotriose; D008320:Maltose; D000516:alpha-Amylases
keywords: Lactobacillus plantarum; glycoside hydrolase (GH) 13; maltose; α-amylase