title: Characterization of a salt-tolerant aminopeptidase from marine Bacillus licheniformis SWJS33 that improves hydrolysis and debittering efficiency for soy protein isolate.
abstract: An aminopeptidase was isolated from the marine Bacillus licheniformis SWJS33 (BLAP) and purified. According to the tandem mass spectrometry, the enzyme displayed 11% amino acid identity with the aminopeptidase from Bacillus (gi|496687392). BLAP exhibited maximum activity at 60°C and pH 8.0-8.5 and had a molecular mass of 100kDa. The presence of NaCl enabled 50% improvement of enzyme activity with 10-15% NaCl being the best. The observed inactivation by EDTA and bestatin and activation by Co(2+) and Ag(+) indicated that the obtained enzyme was a metalloaminopeptidase. Such an aminopeptidase could further improve the hydrolysis degree of soy protein isolate hydrolysates catalyzed by papain, Alcalase 2.4L or Flavourzyme 500MG from 8.5%, 9.5% or 14.4-18.8%, 18.7% or 20.1%, respectively, while decreasing the bitter intensity score of the SPI hydrolysates catalyzed by Alcalase 2.4L from 3.6 to 0.4.
authors: School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510640, China.
authors: Fenfen
authors: F
authors: Lei
authors: School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510640, China.
authors: Qiangzhong
authors: Q
authors: Zhao
authors: School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510640, China; School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors: Dongxiao
authors: D
authors: Sun-Waterhouse
authors: School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 510640, China. Electronic address: femmzhao@scut.edu.cn.
authors: Mouming
authors: M
authors: Zhao
mesh_terms: D000626:Aminopeptidases / Q000302:isolation & purification* / Q000378:metabolism; D000069976:Bacillus licheniformis / Q000378:metabolism*; D004492:Edetic Acid / Q000494:pharmacology; D010450:Endopeptidases / Q000378:metabolism; D006868:Hydrolysis / Q000187:drug effects; D007930:Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D010206:Papain / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology; D030262:Soybean Proteins / Q000378:metabolism*; D013381:Subtilisins / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D030262:Soybean Proteins; D012965:Sodium Chloride; D004492:Edetic Acid; D010450:Endopeptidases; C412470:flavourzyme; D000626:Aminopeptidases; D013381:Subtilisins; D010206:Papain; D007930:Leucine; C012211:ubenimex
keywords: Aminopeptidase; Debittering; Enzyme characteristics; Protein hydrolysis; Salt-tolerant