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Lynch R, Buckin V. Ultrasonic analysis of effects of varying temperature, pH, and proteolytic enzymes on hydrolysis of lactose by neutral lactase formulations in infant milk and in the infant digestive system. Food Res Int 2022; 157:111004. [DOI: 10.1016/j.foodres.2022.111004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 11/28/2022]
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Abstract
The aim of this review was to present various topics related to lactose intolerance with special attention given to the role of fermented foods and probiotics in alleviating gastrointestinal symptoms. Lactose intolerance is a common digestive problem in which the human body is unable to digest lactose, known as milk sugar. Lactose intolerance can either be hereditary or a consequence of intestinal diseases. Recent work has demonstrated that fermented dairy products and probiotics can modify the metabolic activities of colonic microbiota and may alleviate the symptoms of lactose intolerance. We suggest that, lactose free dairy products could be recommended as alternatives for the alleviation of lactose intolerance and for the promotion of human health and wellness.
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Li N, Liu Y, Wang C, Weng P, Wu Z, Zhu Y. Overexpression and characterization of a novel GH4 galactosidase with β-galactosidase activity from Bacillus velezensis SW5. J Dairy Sci 2021; 104:9465-9477. [PMID: 34127264 DOI: 10.3168/jds.2021-20258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 04/26/2021] [Indexed: 12/17/2022]
Abstract
A novel galactosidase gene (gal3149) was identified from Bacillus velezensis SW5 and heterologously expressed in Escherichia coli BL21 (DE3). The novel galactosidase, Gal3149, encoded by gal3149 in an open reading frame of 1,299 bp, was 433 amino acids in length. Protein sequence analysis showed that Gal3149 belonged to family 4 of glycoside hydrolases (GH4). Gal3149 displayed higher enzyme activity for the substrate 2-nitrophenyl-β-d-galactopyranoside (oNPG) than for 4-nitrophenyl-α-d-galactopyranoside (pNPαG). This is the first time that an enzyme belonging to GH4 has been shown to exhibit β-galactosidase activity. Gal3149 showed optimal activity at pH 8.0 and 50°C, and exhibited excellent thermal stability, with retention of 50% relative activity after incubation at a temperature range of 0 to 50°C for 48 h. Gal3149 activity was significantly improved by K+ and Na+, and was strongly or completely inhibited by Ag+, Zn2+, Tween-80, Cu2+, carboxymethyl cellulose, and oleic acid. The rate of hydrolyzed lactose in 1 mL of milk by 1 U of Gal3149 reached about 50% after incubation for 4 h. These properties lay a solid foundation for Gal3149 in application of the lactose-reduced dairy industry.
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Affiliation(s)
- Na Li
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, People's Republic of China
| | - Yang Liu
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, People's Republic of China; Institute of Quality Standards and Testing Technology for Agro-Products, Fujian Academy of Agricultural Sciences, Fuzhou 350003, People's Republic of China
| | - Changyu Wang
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, People's Republic of China
| | - Peifang Weng
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, People's Republic of China
| | - Zufang Wu
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, People's Republic of China.
| | - Yazhu Zhu
- Zhejiang International Maritime College, Zhoushan 316021, People's Republic of China
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Han YY, Yue HY, Zhang XY, Lyu YM, Liu L, Voglmeir J. Construction and Evaluation of Peptide-Linked Lactobacillus brevis β-Galactosidase Heterodimers. Protein Pept Lett 2021; 28:221-228. [PMID: 32798366 DOI: 10.2174/0929866527666200813201242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 06/27/2020] [Accepted: 07/06/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND β-galactosidases are enzymes that are utilized to hydrolyze lactose into galactose and glucose, and are is widely used in the food industry. OBJECTIVE We describe the recombinant expression of an unstudied, heterodimeric β-galactosidase originating from Lactobacillus brevis ATCC 367 in Escherichia coli. Furthermore, six different constructs, in which the two protein subunits were fused with different peptide linkers, were also investigated. METHODS The heterodimeric subunits of the β-galactosidase were cloned in expressed in various expression constructs, by using either two vectors for the independent expression of each subunit, or using a single Duet vector for the co-expression of the two subunits. RESULTS The co-expression in two independent expression vectors only resulted in low β-galactosidase activities, whereas the co-expression in a single Duet vector of the independent and fused subunits increased the β-galactosidase activity significantly. The recombinant β-galactosidase showed comparable hydrolyzing properties towards lactose, N-acetyllactosamine, and pNP-β-D-galactoside. CONCLUSION The usability of the recombinant L. brevis β-galactosidase was further demonstrated by the hydrolysis of human, bovine, and goat milk samples. The herein presented fused β-galactosidase constructs may be of interest for analytical research as well as in food- and biotechnological applications.
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Affiliation(s)
- Yuan-Yuan Han
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Hai-Yun Yue
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Xiao-Yang Zhang
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Yong-Mei Lyu
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Li Liu
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Josef Voglmeir
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
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Xu Y, Wu Q, Bai L, Mu G, Tuo Y, Jiang S, Zhu X, Qian F. Cloning, expression, and bioinformatics analysis and characterization of a β-galactosidase from Bacillus coagulans T242. J Dairy Sci 2021; 104:2735-2747. [PMID: 33455743 DOI: 10.3168/jds.2020-18942] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 10/13/2020] [Indexed: 12/13/2022]
Abstract
The activities of β-galactosidases from bacteria and molds are affected by temperature, pH, and other factors in the processing of dairy products, limiting their application, so it is necessary to find alternative lactases. In this study, the β-galactosidase gene from Bacillus coagulans T242 was cloned, co-expressed with a molecular chaperone in Escherichia coli BL21, and subjected to bioinformatic and kinetic analyses and lactase characterization. The results show that the enzyme is a novel thermostable neutral lactase with optimum hydrolytic activity at pH 6.8 and 50°C. The thermal stability and increased lactose hydrolysis activity of β-galactosidase in the presence of Ca2+ indicated its potential application in the dairy industry.
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Affiliation(s)
- Yunpeng Xu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China
| | - Qiong Wu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China
| | - Li Bai
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China
| | - Guangqing Mu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China
| | - Yanfeng Tuo
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China
| | - Shujuan Jiang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China
| | - Xuemei Zhu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China.
| | - Fang Qian
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China.
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Lynch R, Burke A, Byrne J, Buckin V. Osmolality and molar mass of oligosaccharides in breast milks and infant formula during hydrolysis of lactose. Application of high-resolution ultrasonic spectroscopy. Food Chem 2020; 322:126645. [DOI: 10.1016/j.foodchem.2020.126645] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 10/24/2022]
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Murphy J, Ryan MP, Walsh G. Purification and Characterization of a Novel β-Galactosidase From the Thermoacidophile Alicyclobacillus vulcanalis. Appl Biochem Biotechnol 2020; 191:1190-1206. [DOI: 10.1007/s12010-020-03233-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 01/08/2020] [Indexed: 10/25/2022]
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8
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Purification and characterization of a novel thermophilic β-galactosidase from Picrophilus torridus of potential industrial application. Extremophiles 2019; 23:783-792. [DOI: 10.1007/s00792-019-01133-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 09/13/2019] [Indexed: 12/17/2022]
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Dong L, Zhong Q. Dispersible Biopolymer Particles Loaded with Lactase as a Potential Delivery System To Control Lactose Hydrolysis in Milk. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:6559-6568. [PMID: 31099562 DOI: 10.1021/acs.jafc.9b01546] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
To deliver lactase in milk, dispersible capsules were fabricated by anti-solvent precipitation of zein to form a zein-lactase core and a shell of low-methoxyl sugar beet pectin cross-linked by Ca2+, involving electrostatic, hydrophobic, hydrogen-bonding, and Ca2+-bridging forces. At optimal conditions, an encapsulation efficiency of 93.0% and Z-average diameter of 652.7 nm were observed, and spherical particles smaller than 200 nm were observed in scanning electron microscopy. Contrasting with complete hydrolysis within 1 week by unencapsulated lactase, 50 units/mL encapsulated lactase resulted in 33.1 and 40.0% lactose hydrolysis in whole and skim milk, respectively, after 3 weeks of storage at 4 °C. In separate in vitro digestion assays, 50 units/mL encapsulated lactase resulted in 100% lactose hydrolysis in milk, contrasting with negligible activity by free lactase. These findings suggest the potential of the studied biopolymer particles to incorporate lactase in milk, prevent lactose hydrolysis during storage, and hydrolyze lactose in milk after ingestion.
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Affiliation(s)
- Lianger Dong
- Department of Food Science , University of Tennessee , 2510 River Drive , Knoxville , Tennessee 37996 , United States
| | - Qixin Zhong
- Department of Food Science , University of Tennessee , 2510 River Drive , Knoxville , Tennessee 37996 , United States
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Altas MC, Kudryashov E, Buckin V. Ultrasonic Monitoring of Enzyme Catalysis; Enzyme Activity in Formulations for Lactose-Intolerant Infants. Anal Chem 2016; 88:4714-23. [PMID: 27018312 DOI: 10.1021/acs.analchem.5b04673] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The paper introduces ultrasonic technology for real-time, nondestructive, precision monitoring of enzyme-catalyzed reactions in solutions and in complex opaque media. The capabilities of the technology are examined in a comprehensive analysis of the effects of a variety of diverse factors on the performance of enzyme β-galactosidase in formulations for reduction of levels of lactose in infant milks. These formulations are added to infant's milk bottles prior to feeding to overcome the frequently observed intolerance to lactose (a milk sugar), a serious issue in healthy development of infants. The results highlight important impediments in the development of these formulations and also illustrate the capability of the described ultrasonic tools in the assessment of the performance of enzymes in complex reaction media and in various environmental conditions.
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Affiliation(s)
- Margarida C Altas
- School of Chemistry and Chemical Biology, University College Dublin , Belfield, Dublin 4, Ireland
| | - Evgeny Kudryashov
- School of Chemistry and Chemical Biology, University College Dublin , Belfield, Dublin 4, Ireland
| | - Vitaly Buckin
- School of Chemistry and Chemical Biology, University College Dublin , Belfield, Dublin 4, Ireland
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A thermo-halo-tolerant and proteinase-resistant endoxylanase from Bacillus sp. HJ14. Folia Microbiol (Praha) 2014; 59:423-31. [DOI: 10.1007/s12223-014-0316-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 03/27/2014] [Indexed: 12/13/2022]
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12
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Vincent V, Aghajari N, Pollet N, Boisson A, Boudebbouze S, Haser R, Maguin E, Rhimi M. The acid tolerant and cold-active β-galactosidase from Lactococcus lactis strain is an attractive biocatalyst for lactose hydrolysis. Antonie van Leeuwenhoek 2012. [PMID: 23180374 DOI: 10.1007/s10482-012-9852-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The gene encoding the β-galactosidase from the dairy Lactococcus lactis IL1403 strain was cloned, sequenced and overexpressed in Escherichia coli. The purified enzyme has a tetrameric arrangement composed of four identical 120 kDa subunits. Biochemical characterization showed that it is optimally active within a wide range of temperatures from 15 to 55 °C and of pH from 6.0 to 7.5. For its maximal activity this enzyme requires only 0.8 mM Fe(2+) and 1.6 mM Mg(2+). Purified protein displayed a high catalytic efficiency of 102 s(-1) mM(-1) for lactose. The enzyme stability was increased by immobilization mainly at low pH (from 4.0 to 5.5) and high temperatures (55 and 60 °C). The bioconversion of lactose using the L. lactis β-galactosidase allows the production of lactose with a high bioconversion rate (98 %) within a wide range of pH and temperature.
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Affiliation(s)
- Violette Vincent
- Laboratory for Biocrystallography and Structural Biology of Therapeutic Targets, Bases Moléculaires des Systèmes Infectieux-UMR 5086, CNRS/Université de Lyon 1, Institut de Biologie et Chimie des Protéines-FR3302, 7 Passage du Vercors, 69367, Lyon Cedex 07, France
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Yuan P, Meng K, Wang Y, Luo H, Shi P, Huang H, Bai Y, Yang P, Yao B. A protease-resistant exo-polygalacturonase from Klebsiella sp. Y1 with good activity and stability over a wide pH range in the digestive tract. BIORESOURCE TECHNOLOGY 2012; 123:171-176. [PMID: 22940315 DOI: 10.1016/j.biortech.2012.07.037] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 06/02/2012] [Accepted: 07/13/2012] [Indexed: 06/01/2023]
Abstract
Polygalacturonases are important feed and food additives. In the present study an exo-polygalacturonase gene (pgu B) was cloned from Klebsiella sp. Y1 CGMCC 4433 and expressed in Escherichia coli BL21 (DE3). pgu B encodes a 658-amino acid polypeptide belonging to Glycoside Hydrolase Family 28. The optimal pH and temperature of exo-PGU B activity were 6.0 and 40-50°C, respectively. The enzyme exhibited >35% of maximum activity within the pH range of 2.0-12.0. Exo-PGU B or an exo-PGU B/ endo-polygalacturonase mixture reduced the viscosity of polygalacturonic acid (1.0%, w/v) by 15.6 and 39.4%, respectively. Under simulated alimentary tract conditions, exo-PGU B was very stable (>25% activity from pH 1.5 to 6.8) and active, releasing 53.7 and 109.6μg of galacturonic acid from 400 to 800μg of polygalacturonic acid, respectively. These properties make exo-PGU B a potentially valuable additive for applications in feed and food.
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Affiliation(s)
- Peng Yuan
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
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14
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Oliveira de Medeiros F, Veiga Burkert CA, Juliano Kalil S. Purification of β-Galactosidase by Ion Exchange Chromatography: Elution Optimization Using an Experimental Design. Chem Eng Technol 2012. [DOI: 10.1002/ceat.201100571] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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15
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Stabilization of a supplemental digestive enzyme by post-translational engineering using chemically-activated polyethylene glycol. Biotechnol Lett 2010; 33:617-21. [DOI: 10.1007/s10529-010-0474-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Accepted: 11/04/2010] [Indexed: 10/18/2022]
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16
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Juajun O, Nguyen TH, Maischberger T, Iqbal S, Haltrich D, Yamabhai M. Cloning, purification, and characterization of β-galactosidase from Bacillus licheniformis DSM 13. Appl Microbiol Biotechnol 2010; 89:645-54. [PMID: 20852995 DOI: 10.1007/s00253-010-2862-2] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2010] [Revised: 08/21/2010] [Accepted: 08/23/2010] [Indexed: 12/24/2022]
Abstract
The gene encoding homodimeric β-galactosidase (lacA) from Bacillus licheniformis DSM 13 was cloned and overexpressed in Escherichia coli, and the resulting recombinant enzyme was characterized in detail. The optimum temperature and pH of the enzyme, for both o-nitrophenyl-β-D: -galactoside (oNPG) and lactose hydrolysis, were 50°C and 6.5, respectively. The recombinant enzyme is stable in the range of pH 5 to 9 at 37°C and over a wide range of temperatures (4-42°C) at pH 6.5 for up to 1 month. The K(m) values of LacA for lactose and oNPG are 169 and 13.7 mM, respectively, and it is strongly inhibited by the hydrolysis products, i.e., glucose and galactose. The monovalent ions Na(+) and K(+) in the concentration range of 1-100 mM as well as the divalent metal cations Mg²(+), Mn²(+), and Ca²(+) at a concentration of 1 mM slightly activate enzyme activity. This enzyme can be beneficial for application in lactose hydrolysis especially at elevated temperatures due to its pronounced temperature stability; however, the transgalactosylation potential of this enzyme for the production of galacto-oligosaccharides (GOS) from lactose was low, with only 12% GOS (w/w) of total sugars obtained when the initial lactose concentration was 200 g/L.
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Affiliation(s)
- Onladda Juajun
- Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
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Engineering of a fungal β-galactosidase to remove product inhibition by galactose. Appl Microbiol Biotechnol 2010; 87:1773-82. [DOI: 10.1007/s00253-010-2662-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Revised: 04/27/2010] [Accepted: 04/29/2010] [Indexed: 10/19/2022]
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18
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A novel acid-stable, acid-active β-galactosidase potentially suited to the alleviation of lactose intolerance. Appl Microbiol Biotechnol 2009; 86:517-24. [DOI: 10.1007/s00253-009-2270-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Revised: 09/18/2009] [Accepted: 09/20/2009] [Indexed: 10/20/2022]
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19
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Wang H, Luo H, Bai Y, Wang Y, Yang P, Shi P, Zhang W, Fan Y, Yao B. An acidophilic beta-galactosidase from Bispora sp. MEY-1 with high lactose hydrolytic activity under simulated gastric conditions. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:5535-5541. [PMID: 19453169 DOI: 10.1021/jf900369e] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
BgalA, a full-length gene (3,009 bp) that encodes a beta-galactosidase, was cloned from the meso-acidophilic fungus Bispora sp. MEY-1 and expressed in Pichia pastoris. The deduced amino acid sequence of BgalA shares highest identity (55.5%) with the beta-galactosidase from Aspergillus phoenicis, which belongs to the glycoside hydrolyase family 35. Purified recombinant BgalA is acidophilic, exhibiting maximum activity at pH 1.5, which is lower than that reported for other beta-galactosidases. The enzyme has high pH and thermal stability and is resistant to proteases and cations found in milk. The K(m) and V(max) of BgalA for 2-nitrophenyl-beta-D-galactopyranoside and lactose are 5.22 mM and 120.8 micromol/(min x mg), and 0.31 mM and 137.3 micromol/(min x mg), respectively. Under simulated gastric conditions, BgalA has greater stability ( approximately 100%) and hydrolysis ratio (>80%) toward milk lactose than the commercially available beta-galactosidase from Aspergillus oryzae (ATCC 20423). Thus, BgalA may be a better digestive supplement for alleviating symptoms associated with lactase deficiency.
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Affiliation(s)
- Hui Wang
- Key Laboratory of Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People's Republic of China
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