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Gennari A, Simon R, de Andrade BC, Kuhn D, Renard G, Chies JM, Volpato G, Volken de Souza CF. Recombinant Production in Escherichia coli of a β-galactosidase Fused to a Cellulose-binding Domain Using Low-cost Inducers in Fed-batch Cultivation. Process Biochem 2022. [DOI: 10.1016/j.procbio.2022.11.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Singh RV, Sambyal K. β-galactosidase as an industrial enzyme: production and potential. CHEMICAL PAPERS 2022. [DOI: 10.1007/s11696-022-02507-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Luan S, Duan X. A Novel Thermal-Activated β-Galactosidase from Bacillus aryabhattai GEL-09 for Lactose Hydrolysis in Milk. Foods 2022; 11:foods11030372. [PMID: 35159524 PMCID: PMC8834341 DOI: 10.3390/foods11030372] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/09/2022] [Accepted: 01/25/2022] [Indexed: 02/01/2023] Open
Abstract
β-Galactosidase has been greatly used in the dairy industry. This study investigated a novel thermostable β-galactosidase (lacZBa) from Bacillus aryabhattai GEL-09 and evaluated the hydrolytic performance of this enzyme. Firstly, the lacZBa-encoding gene was cloned and overexpressed in Escherichia coli BL21(DE3). Phylogenetic analyses revealed that lacZBa belonged to the glycoside hydrolase family 42. Using SDS-PAGE, we determined that the molecular weight of lacZBa was ~75 kDa. Purified lacZBa exhibited a maximum activity at 45 °C, pH 6.0, and could be activated following incubation at 45 °C for several minutes. The half-life of lacZBa at 45 °C and 50 °C was 264 h and 36 h, respectively. While Co2+, Mn2+, Zn2+, Fe2+, Mg2+, and Ca2+ enhanced enzymatic activity, Cu2+ and ethylenediaminetetraacetic acid inhibited enzymatic activity. Moreover, lacZBa could hydrolyze lactose and oNPG with Km values of 85.09 and 14.38 mM. Molecular docking results revealed that lacZBa efficiently recognized and catalyzed lactose. Additionally, the hydrolysis of lactose by lacZBa was studied in lactose solution and commercial milk. Lactose was completely hydrolyzed within 4 h with 8 U/mL of lacZBa at 45 °C. These results suggested that lacZBa identified in this study has potential applications in the dairy industry.
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Cui L, Qiu Y, Liang Y, Du C, Dong W, Cheng C, He B. Excretory expression of IsPETase in E. coli by an enhancer of signal peptides and enhanced PET hydrolysis. Int J Biol Macromol 2021; 188:568-575. [PMID: 34371048 DOI: 10.1016/j.ijbiomac.2021.08.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/10/2021] [Accepted: 08/03/2021] [Indexed: 10/20/2022]
Abstract
The PET hydrolase from Ideonella sakaiensis (IsPETase) is efficient for PET degradation, which provides a promising solution for environmental contamination by plastics. This study focuses on improving the excretion of IsPETase from E. coli by signal peptide (SP) engineering. A SP enhancer B1 (MERACVAV) was fused to the N-terminal of commonly-used SP (PelB, MalE, LamB, and OmpA) to mediate excretion of IsPETase. Strikingly, the modified SP B1OmpA, B1PelB, and B1MalE significantly increased the excretion of IsPETase, while IsPETase was basically expressed in periplasmic space without enhancer B1. The excretion efficiency of IsPETase mediated by B1PelB was improved by 62 folds compared to that of PelB. The hydrolysis of PET by crude IsPETase in culture solution was also enhanced. Furthermore, the amount of released MHET/TPA from PET by IsPETase was increased by 2.7 folds with pre-incubation of hydrophobin HFBII. Taken together, this work may provide a feasible strategy for the excretion and application of the IsPETase.
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Affiliation(s)
- Lupeng Cui
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing 211816, China
| | - Yumeng Qiu
- School of Pharmaceutical Sciences, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing 211816, China
| | - Yu Liang
- 2011 College, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing 211816, China
| | - Chunjie Du
- 2011 College, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing 211816, China
| | - Weiliang Dong
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing 211816, China
| | - Cheng Cheng
- School of Pharmaceutical Sciences, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing 211816, China.
| | - Bingfang He
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing 211816, China; School of Pharmaceutical Sciences, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing 211816, China.
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Gennari A, Simon R, de Andrade BC, Saraiva Macedo Timmers LF, Milani Martins VL, Renard G, Chies JM, Volpato G, Volken de Souza CF. Production of beta-galactosidase fused to a cellulose-binding domain for application in sustainable industrial processes. BIORESOURCE TECHNOLOGY 2021; 326:124747. [PMID: 33517047 DOI: 10.1016/j.biortech.2021.124747] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/14/2021] [Accepted: 01/15/2021] [Indexed: 06/12/2023]
Abstract
This study aimed to produce and characterize a recombinant Kluyveromyces sp. β-galactosidase fused to a cellulose-binding domain (CBD) for industrial application. In expression assays, the highest enzymatic activities occurred after 48 h induction on Escherichia coli C41(DE3) strain at 20 °C in Terrific Broth (TB) culture medium, using isopropyl β-d-1-thiogalactopyranoside (IPTG) 0.5 mM (108.77 U/mL) or lactose 5 g/L (93.10 U/mL) as inducers. Cultures at bioreactor scale indicated that higher product yield values in relation to biomass (2000 U/g) and productivity (0.72 U/mL.h) were obtained in culture media containing higher protein concentration. The recombinant enzyme showed high binding affinity to nanocellulose, reaching both immobilization yield and efficiency values of approximately 70% at pH 7.0 after 10 min reaction. The results of the present study pointed out a strategy for recombinant β-galactosidase-CBD production and immobilization, aiming toward the application in sustainable industrial processes using low-cost inputs.
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Affiliation(s)
- Adriano Gennari
- Laboratório de Biotecnologia de Alimentos, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil; Programa de Pós-Graduação em Biotecnologia, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil
| | - Renate Simon
- Laboratório de Biotecnologia de Alimentos, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil
| | - Bruna Coelho de Andrade
- Laboratório de Biotecnologia de Alimentos, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil; Programa de Pós-Graduação em Biotecnologia, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil
| | | | - Vera Lúcia Milani Martins
- Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul - IFRS, Campus Porto Alegre, Porto Alegre, RS, Brazil
| | - Gaby Renard
- Centro de Pesquisa em Biologia Molecular e Funcional, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | | | - Giandra Volpato
- Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul - IFRS, Campus Porto Alegre, Porto Alegre, RS, Brazil
| | - Claucia Fernanda Volken de Souza
- Laboratório de Biotecnologia de Alimentos, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil; Programa de Pós-Graduação em Biotecnologia, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil.
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Shahzadi I, Al-Ghamdi MA, Nadeem MS, Sajjad M, Ali A, Khan JA, Kazmi I. Scale-up fermentation of Escherichia coli for the production of recombinant endoglucanase from Clostridium thermocellum. Sci Rep 2021; 11:7145. [PMID: 33785771 PMCID: PMC8009960 DOI: 10.1038/s41598-021-86000-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 03/01/2021] [Indexed: 02/01/2023] Open
Abstract
Endoglucanase (EC 3.2.1.4) catalysing the hydrolysis of β-1.4-glycosidic linkage of cellulose molecules is an enzyme of tremendous industrial importance. The present study describes a response surface methodology based predicted model to deduce a set of fermentation conditions for optimum growth and activity of recombinant endoglucanase in E. coli BL21 (DE3). Numerous significant parameters including fermentation media composition, temperature (Celsius), pH and agitation rate (rpm) were analysed systemically by employing central composite design. This effort reports highly efficient recombinant endoglucanase overproduction (6.9 gl-1 of biomass) with 30% expression by E. coli in modified M9NG media incubated at 37 °C and pH 7 agitated at 200 rpm. Addition of 3 mM glucose and 24 mM glycerol in the M9NG media has shown positive effect on the enzyme yield and activity. The CMCase activity experimentally estimated was found to be 1185 U/mg with the optimized parameters. The outcomes of both the responses by the predicted quadratic model were found in consensus with the obtained values. Our results well depicted the favourable conditions to further scale-up the volumetric yield of other relevant recombinant enzymes and proteins.
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Affiliation(s)
- Iram Shahzadi
- grid.440564.70000 0001 0415 4232Institute of Molecular Biology and Biotechnology, University of Lahore, Defence Road Campus, Lahore, 54590 Pakistan
| | - Maryam A. Al-Ghamdi
- grid.412125.10000 0001 0619 1117Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah, 21589 Saudi Arabia
| | - Muhammad Shahid Nadeem
- grid.412125.10000 0001 0619 1117Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah, 21589 Saudi Arabia
| | - Muhammad Sajjad
- grid.440564.70000 0001 0415 4232Institute of Molecular Biology and Biotechnology, University of Lahore, Defence Road Campus, Lahore, 54590 Pakistan ,grid.11173.350000 0001 0670 519XSchool of Biological Sciences, University of the Punjab, Lahore, 54590 Pakistan
| | - Asif Ali
- grid.440564.70000 0001 0415 4232Institute of Molecular Biology and Biotechnology, University of Lahore, Defence Road Campus, Lahore, 54590 Pakistan
| | - Jalaluddin Azam Khan
- grid.412125.10000 0001 0619 1117Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah, 21589 Saudi Arabia
| | - Imran Kazmi
- grid.412125.10000 0001 0619 1117Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah, 21589 Saudi Arabia
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Movahedpour A, Ahmadi N, Ghalamfarsa F, Ghesmati Z, Khalifeh M, Maleksabet A, Shabaninejad Z, Taheri-Anganeh M, Savardashtaki A. β-Galactosidase: From its source and applications to its recombinant form. Biotechnol Appl Biochem 2021; 69:612-628. [PMID: 33656174 DOI: 10.1002/bab.2137] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/19/2021] [Indexed: 12/12/2022]
Abstract
Carbohydrate-active enzymes are a group of important enzymes playing a critical role in the degradation and synthesis of carbohydrates. Glycosidases can hydrolyze glycosides into oligosaccharides, polysaccharides, and glycoconjugates via a cost-effective approach. Lactase is an important member of β-glycosidases found in higher plants, animals, and microorganisms. β-Galactosidases can be used to degrade the milk lactose for making lactose-free milk, which is sweeter than regular milk and is suitable for lactose-intolerant people. β-Galactosidase is employed by many food industries to degrade lactose and improve the digestibility, sweetness, solubility, and flavor of dairy products. β-Galactosidase enzymes have various families and are applied in the food-processing industries such as hydrolyzed-milk products, whey, and galactooligosaccharides. Thus, this enzyme is a valuable protein which is now produced by recombinant technology. In this review, origins, structure, recombinant production, and critical modifications of β-galactosidase for improving the production process are discussed. Since β-galactosidase is a valuable enzyme in industry and health care, a study of its various aspects is important in industrial biotechnology and applied biochemistry.
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Affiliation(s)
- Ahmad Movahedpour
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran.,Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Nahid Ahmadi
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Farideh Ghalamfarsa
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Zeinab Ghesmati
- Department of Medical Biotechnology, School of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Masoomeh Khalifeh
- Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Amir Maleksabet
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Zahra Shabaninejad
- Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.,Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mortaza Taheri-Anganeh
- Shahid Arefian Hospital, Urmia, Iran.,Cellular and Molecular Research Center, Cellular and Molecular Medicine Institute, Urmia University of Medical Sciences, Urmia, Iran
| | - Amir Savardashtaki
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran.,Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
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Mobayed FH, Nunes JC, Gennari A, de Andrade BC, Ferreira MLV, Pauli P, Renard G, Chies JM, Volpato G, Volken de Souza CF. Effect of by-products from the dairy industry as alternative inducers of recombinant β-galactosidase expression. Biotechnol Lett 2020; 43:589-599. [PMID: 33052483 DOI: 10.1007/s10529-020-03028-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 10/09/2020] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The aim of the present study was to evaluate the efficiency of lactose derived from cheese whey and cheese whey permeate as inducer of recombinant Kluyveromyces sp. β-galactosidase enzyme produced in Escherichia coli. Two E. coli strains, BL21(DE3) and Rosetta (DE3), were used in order to produce the recombinant enzyme. Samples were evaluated for enzyme activity, total protein content, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis after induction with isopropyl-β-D-1-thiogalactoside (IPTG) (0.05 and 1 mM) and lactose, cheese whey, and cheese whey permeate solutions (1, 10, and 20 g/L lactose) at shake-flask cultivation, and whey permeate solution (10 g/L lactose) at bioreactor scale. RESULTS The highest specific activities obtained with IPTG as inducer (0.05 mM) after 9 h of induction, were 23 and 33 U/mgprotein with BL21(DE3) and Rosetta(DE3) strains, respectively. Inductions performed with lactose and cheese whey permeate (10 and 20 g/L lactose) showed the highest specific activities at the evaluated hours, exhibiting better results than those obtained with IPTG. Specific activity of recombinant β-galactosidase using whey permeate (10 g/L lactose) showed values of approximately 46 U/mgprotein after 24-h induction at shake-flask study, and approximately 26 U/mgprotein after 16-h induction at bench bioreactor. CONCLUSIONS The induction with cheese whey permeate was more efficient for recombinant β-galactosidase expression than the other inducers tested, and thus, represents an alternative form to reduce costs in recombinant protein production.
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Affiliation(s)
- Francielle Herrmann Mobayed
- Laboratório de Biotecnologia de Alimentos, Universidade do Vale do Taquari - Univates, Av. Avelino Tallini, 171, ZC, Lajeado, RS, 95914-014, Brazil
| | - Juliane Carraro Nunes
- Curso de Biotecnologia, Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul - IFRS, Campus Porto Alegre, Porto Alegre, RS, Brazil
| | - Adriano Gennari
- Laboratório de Biotecnologia de Alimentos, Universidade do Vale do Taquari - Univates, Av. Avelino Tallini, 171, ZC, Lajeado, RS, 95914-014, Brazil
- Programa de Pós-Graduação em Biotecnologia, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil
| | - Bruna Coelho de Andrade
- Laboratório de Biotecnologia de Alimentos, Universidade do Vale do Taquari - Univates, Av. Avelino Tallini, 171, ZC, Lajeado, RS, 95914-014, Brazil
- Programa de Pós-Graduação em Biotecnologia, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil
| | - Matheus Loch Velvites Ferreira
- Curso de Biotecnologia, Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul - IFRS, Campus Porto Alegre, Porto Alegre, RS, Brazil
| | - Paolla Pauli
- Curso de Biotecnologia, Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul - IFRS, Campus Porto Alegre, Porto Alegre, RS, Brazil
| | - Gaby Renard
- Centro de Pesquisa em Biologia Molecular e Funcional, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | | | - Giandra Volpato
- Curso de Biotecnologia, Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul - IFRS, Campus Porto Alegre, Porto Alegre, RS, Brazil
| | - Claucia Fernanda Volken de Souza
- Laboratório de Biotecnologia de Alimentos, Universidade do Vale do Taquari - Univates, Av. Avelino Tallini, 171, ZC, Lajeado, RS, 95914-014, Brazil.
- Programa de Pós-Graduação em Biotecnologia, Universidade do Vale do Taquari - Univates, Lajeado, RS, Brazil.
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Elsayed EA, Danial EN, Wadaan MA, El-Enshasy HA. Production of β-galactosidase in shake-flask and stirred tank bioreactor cultivations by a newly isolated Bacillus licheniformis strain. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.101231] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Enhanced L-methionine production by genetically engineered Escherichia coli through fermentation optimization. 3 Biotech 2019; 9:96. [PMID: 30800607 DOI: 10.1007/s13205-019-1609-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 02/01/2019] [Indexed: 12/13/2022] Open
Abstract
Microbial fermentation for L-methionine (L-Met) production based on natural renewable resources is attractive and challenging. In this work, the effects of medium composition and fermentation conditions were investigated to improve L-Met production by genetically engineered Escherichia coli MET-3. Statistical optimization techniques including Plackett-Burman (PB) design and Box-Behnken design (BBD) were adopted first to optimize the culture medium. Results of PB-designed experiments indicated that the culture medium components including glucose, yeast extract, KH2PO4, and MgSO4.7H2O had significant effects on L-Met biosynthesis. With their best-predicted concentration established by BBD (glucose 37.43 g/L, yeast extract 0.95 g/L, KH2PO4 1.82 g/L, and MgSO4.7H2O 4.51 g/L), L-Met titer was increased to 3.04 g/L from less than 2.0 g/L. For further enhancement of L-Met biosynthesis, the fermentation conditions of batch cultivation carried out in a 5-L fermentor were optimized, and the optimum results were obtained at an agitation rate of 300 rpm, medium pH of 7.0, and induction temperature of 28 °C. Based on the optimization parameters, fed-batch fermentation with the modified medium was conducted. As a result, great improvement of L-Met titer (12.80 g/L) and yield (0.13 mol/mol) were achieved, with an increase of 38.53% and 30.0% compared with those of the basal medium, respectively. Furthermore, higher L-Met productivity of 0.261 g/L/h was obtained, representing 2.13-fold higher in comparison to the original medium. The results may provide a helpful reference for further study on strain improvement and fermentation control.
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Biochemical characterization of a novel β-galactosidase from Paenibacillus barengoltzii suitable for lactose hydrolysis and galactooligosaccharides synthesis. Int J Biol Macromol 2017; 104:1055-1063. [PMID: 28652150 DOI: 10.1016/j.ijbiomac.2017.06.073] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 06/03/2017] [Accepted: 06/15/2017] [Indexed: 11/23/2022]
Abstract
A β-galactosidase gene (PbBGal2A) was cloned from Paenibacillus barengoltzii and expressed in Escherichia coli. The in silico analysis of the deduced amino acid sequences revealed that PbBGal2A shared the highest identity of 40% with the characterized glycoside hydrolase (GH) family 2 β-galactosidase from Actinobacillus pleuropneumoniae. The recombinant β-galactosidase (PbBGal2A) was purified with a molecular mass of 124.2kDa on SDS-PAGE. The optimal pH and temperature of PbBGal2A were determined to be pH 7.5 and 45°C, respectively. PbBGal2A was stable within pH 6.0-8.0 and up to 45°C. It completely hydrolyzed the lactose in milk and whey powder solution. In addition, PbBGal2A exhibited high transglycosylation activity and a maximum yield of 47.9% (w/w) for galactooligosaccharides (GOS) production was obtained in 8h at a lactose concentration of 350g/L. These properties make PbBGal2A an ideal candidate for commercial use in the production of lactose-free milk and GOS.
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