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Huang J, Zhang D, Omedi JO, Lei Y, Su X, Wu M, Huang W. Improving the inhibitory resistance of xylanase FgXyn11C from Fusarium graminearum to SyXIP-I by site-directed mutagenesis. Int J Biol Macromol 2024; 271:132434. [PMID: 38788879 DOI: 10.1016/j.ijbiomac.2024.132434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024]
Abstract
The aim of this study was to improve the inhibitory resistance of xylanase FgXyn11C from Fusarium graminearum to XIP in cereal flour. Site saturation mutagenesis was performed using computer-aided redesign. Firstly, based on multiple primary structure alignments, the amino acid residues in the active site architecture were identified, and specific residue T144 in the thumb region of FgXyn11C was selected for site-saturation mutagenesis. After screening, FgXyn11CT144F was selected as the best mutant, as it displayed the highest enzymatic activity and resistance simultaneously compared to other mutants. The specific activity of FgXyn11CT144F was 208.8 U/mg and it exhibited complete resistance to SyXIP-I. Compared with the wild-type, FgXyn11CT144F displayed similar activity and the most resistant against SyXIP-I. The optimal temperature and pH of the wild-type and purified FgXyn11CT144F were similar at pH 5.0 and 30 °C. Our findings provided preliminary insight into how the specific residue at position 144 in the thumb region of FgXyn11C influenced the enzymatic properties and interacted with SyXIP-I. The inhibition sensitivity of FgXyn11C was reduced through directed evolution, leading to creation of the mutant enzyme FgXyn11CT144F. The FgXyn11CT144F resistance to SyXIP-I has potential application and can also provide references for engineering other resistant xylanases of the GHF11.
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Affiliation(s)
- Jing Huang
- State Key Laboratory of Food Science and Technology, the Laboratory of Baking and Fermentation Science, Cereals/Sourdough and Ingredient Functionality Research, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Dong Zhang
- School of Biotechnology, Jiangnan University, Wuxi 214122, China; Wuxi School of Medicine, Jiangnan University, Wuxi 214122, China
| | - Jacob Ojobi Omedi
- State Key Laboratory of Food Science and Technology, the Laboratory of Baking and Fermentation Science, Cereals/Sourdough and Ingredient Functionality Research, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Yuqing Lei
- School of Biotechnology, Jiangnan University, Wuxi 214122, China; Wuxi School of Medicine, Jiangnan University, Wuxi 214122, China
| | - Xiaoya Su
- School of Biotechnology, Jiangnan University, Wuxi 214122, China; Wuxi School of Medicine, Jiangnan University, Wuxi 214122, China
| | - Minchen Wu
- Wuxi School of Medicine, Jiangnan University, Wuxi 214122, China.
| | - Weining Huang
- State Key Laboratory of Food Science and Technology, the Laboratory of Baking and Fermentation Science, Cereals/Sourdough and Ingredient Functionality Research, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
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Zhang D, Huang J, Liu Y, Chen X, Gao T, Li N, Huang W, Wu M. Directed Modification of a GHF11 Thermostable Xylanase AusM for Enhancing Inhibitory Resistance towards SyXIP-I and Application of AusM PKK in Bread Making. Foods 2023; 12:3574. [PMID: 37835228 PMCID: PMC10572589 DOI: 10.3390/foods12193574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/21/2023] [Accepted: 09/23/2023] [Indexed: 10/15/2023] Open
Abstract
To reduce the inhibition sensitivity of a thermoresistant xylanase AusM to xylanase inhibitor protein (XIP)-type in wheat flour, the site-directed mutagenesis was conducted based on the computer-aided redesign. First, fourteen single-site variants and one three-amino acid replacement variant in the thumb region of an AusM-encoding gene (AusM) were constructed and expressed in E. coli BL21(DE3), respectively, as predicted theoretically. At a molar ratio of 100:1 between SyXIP-I/xylanase, the majority of mutants were nearly completely inactivated by the inhibitor SyXIP-I, whereas AusMN127A retained 62.7% of its initial activity and AusMPKK retained 100% of its initial activity. The optimal temperature of the best mutant AusMPKK was 60 °C, as opposed to 60-65 °C for AusM, while it exhibited improved thermostability, retaining approximately 60% of its residual activity after heating at 80 °C for 60 min. Furthermore, AusMPKK at a dosage of 1000 U/kg was more effective than AusM at 4000 U/kg in increasing specific bread loaf volume and reducing hardness during bread production and storage. Directed evolution of AusM significantly reduces inhibition sensitivity, and the mutant enzyme AusMPKK is conducive to improving bread quality and extending its shelf life.
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Affiliation(s)
- Dong Zhang
- Wuxi School of Medicine, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Jing Huang
- State Key Laboratory of Food Science and Technology, and the Laboratory of Baking and Fermentation Science, Cereals/Sourdough and Nutritional Functionality Research, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Youyi Liu
- Wuxi School of Medicine, Jiangnan University, Wuxi 214122, China
| | - Xingyi Chen
- Wuxi School of Medicine, Jiangnan University, Wuxi 214122, China
| | - Tiecheng Gao
- Guangzhou Puratos Food Co., Ltd., Guangzhou 511400, China
| | - Ning Li
- Guangzhou Puratos Food Co., Ltd., Guangzhou 511400, China
| | - Weining Huang
- State Key Laboratory of Food Science and Technology, and the Laboratory of Baking and Fermentation Science, Cereals/Sourdough and Nutritional Functionality Research, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Minchen Wu
- Wuxi School of Medicine, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
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Tundo S, Mandalà G, Sella L, Favaron F, Bedre R, Kalunke RM. Xylanase Inhibitors: Defense Players in Plant Immunity with Implications in Agro-Industrial Processing. Int J Mol Sci 2022; 23:ijms232314994. [PMID: 36499321 PMCID: PMC9739030 DOI: 10.3390/ijms232314994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/17/2022] [Accepted: 11/22/2022] [Indexed: 12/03/2022] Open
Abstract
Xylanase inhibitors (XIs) are plant cell wall proteins largely distributed in monocots that inhibit the hemicellulose degrading activity of microbial xylanases. XIs have been classified into three classes with different structures and inhibition specificities, namely Triticum aestivum xylanase inhibitors (TAXI), xylanase inhibitor proteins (XIP), and thaumatin-like xylanase inhibitors (TLXI). Their involvement in plant defense has been established by several reports. Additionally, these inhibitors have considerable economic relevance because they interfere with the activity of xylanases applied in several agro-industrial processes. Previous reviews highlighted the structural and biochemical properties of XIs and hypothesized their role in plant defense. Here, we aimed to update the information on the genomic organization of XI encoding genes, the inhibition properties of XIs against microbial xylanases, and the structural properties of xylanase-XI interaction. We also deepened the knowledge of XI regulation mechanisms in planta and their involvement in plant defense. Finally, we reported the recently studied strategies to reduce the negative impact of XIs in agro-industrial processes and mentioned their allergenicity potential.
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Affiliation(s)
- Silvio Tundo
- Department of Land, Environment, Agriculture, and Forestry (TESAF), University of Padova, 35020 Legnaro, Italy
- Correspondence:
| | - Giulia Mandalà
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Luca Sella
- Department of Land, Environment, Agriculture, and Forestry (TESAF), University of Padova, 35020 Legnaro, Italy
| | - Francesco Favaron
- Department of Land, Environment, Agriculture, and Forestry (TESAF), University of Padova, 35020 Legnaro, Italy
| | - Renesh Bedre
- Texas A&M AgriLife Research and Extension Center, Texas A&M University System, Weslaco, TX 78596, USA
| | - Raviraj M. Kalunke
- Donald Danforth Plant Science Center, 975 N Warson Rd, 7 Olivette, St. Louis, MO 63132, USA
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Li X, Zhang L, Jiang Z, Liu L, Wang J, Zhong L, Yang T, Zhou Q, Dong W, Zhou J, Ye X, Li Z, Huang Y, Cui Z. A novel cold-active GH8 xylanase from cellulolytic myxobacterium and its application in food industry. Food Chem 2022; 393:133463. [PMID: 35751210 DOI: 10.1016/j.foodchem.2022.133463] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 05/31/2022] [Accepted: 06/09/2022] [Indexed: 11/17/2022]
Abstract
Although xylanase have a wide range of applications, cold-active xylanases have received less attention. In this study, a novel glycoside hydrolase family 8 (GH8) xylanase from Sorangium cellulosum with high activity at low temperatures was identified. The recombinant xylanase (XynSc8) was most active at 50 °C, demonstrating 20% of its maximum activity and strict substrate specificity towards beechwood and corncob xylan at 4 °C with Vmax values of 968.65 and 1521.13 μmol/mg/min, respectively. Mesophilic XynSc8 was active at a broad range of pH and hydrolyzed beechwood and corncob xylan into xylooligosaccharides (XOS) with degree of polymerization greater than 3. Moreover, incorporation of XynSc8 (0.05-0.2 mg/kg flour) provided remarkable improvement (28-30%) in bread specific volume and textural characteristics of bread compared to commercial xylanase. This is the first report on a novel cold-adapted GH8 xylanase from myxobacteria, suggesting that XynSc8 may be a promising candidate suitable for bread making.
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Affiliation(s)
- Xu Li
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Lei Zhang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhitong Jiang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Lin Liu
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jihong Wang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Lingli Zhong
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Tao Yang
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Qin Zhou
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China
| | - Jie Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China
| | - Xianfeng Ye
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhoukun Li
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
| | - Yan Huang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhongli Cui
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Biological Interactions and Crop Health, Nanjing Agricultural University, Nanjing 210095, China
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Exploring competitive inhibition of a family 10 xylanase derived from Hu sheep rumen microbiota by Oryza sativa xylanase inhibitor protein: In vitro and in silico perspectives. Enzyme Microb Technol 2022; 160:110082. [PMID: 35709658 DOI: 10.1016/j.enzmictec.2022.110082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/20/2022] [Accepted: 06/09/2022] [Indexed: 01/18/2023]
Abstract
The catalytic domain of family GH10 xylanase, XYN-LXY_CD derived from Hu sheep rumen microbiota was expressed in Pichia pastoris X33. The special activity of reXYN-LXY_CD in the culture supernatant was 232.56 U/mg. The optima of reXYN-LXY_CD were 53 °C and pH 7.0. Recombinant Oryza sativa xylanase inhibitor protein (rePOsXIP) competitively inhibited reXYN-LXY_CD with an inhibition constant (Ki) value of 237.37 nM. The concentration of hydrolysates released from beechwood xylan by reXYN-LXY_CD reduced when rePOsXIP was added into the hydrolytic system. Fluorescence of reXYN-LXY_CD was statically quenched by rePOsXIP in a dose-dependent manner. The details in intermolecular interaction between XYN-LXY_CD and OsXIP were investigated by using molecular dynamics (MD) simulations, binding free energy computation and non-covalent interactions (NCI) analysis. Hydrogen bonding and van der Waals played indispensable roles in the XYN-LXY_CD/OsXIP interaction. The α-7 helix of OsXIP tightly occupied the catalytic pocket of XYN-LXY_CD with hydrogen bonding such as K239OsXIP-N261/Q292/E197XYN-LXY_CD (E197, the acid-base catalytic residue), D236OsXIP-K327XYN-LXY_CD and Q242OsXIP-E211/Q212XYN-LXY_CD. Based on the quantum theory of atoms in molecules (QTAIM), the Laplacian of electron density and core-valence bifurcation index of HZ3K239-OE2E197 were 0.1025 a.u. and 0.002218, respectively. Elucidating the mechanism underlying xylanase-inhibitor interactions might help construct XYN-LXY_CD mutants that gain resistance to XIPs and high catalytic activity, which would be more efficient in feed additives in livestock.
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Sun Z, Zhang M, An Y, Han X, Guo B, Lv G, Zhao Y, Guo Y, Li S. CRISPR/Cas9-Mediated Disruption of Xylanase inhibitor protein ( XIP) Gene Improved the Dough Quality of Common Wheat. FRONTIERS IN PLANT SCIENCE 2022; 13:811668. [PMID: 35449885 PMCID: PMC9018002 DOI: 10.3389/fpls.2022.811668] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/02/2022] [Indexed: 06/14/2023]
Abstract
The wheat dough quality is of great significance for the end-use of flour. Some genes have been cloned for controlling the protein fractions, grain protein content, starch synthase, grain hardness, etc. Using a unigene map of the recombinant inbred lines (RILs) for "TN 18 × LM 6," we mapped a quantitative trait locus (QTL) for dough stability time (ST) and SDS-sedimentation values (SV) on chromosome 6A (QSt/Sv-6A-2851). The peak position of the QTL covered two candidate unigenes, and we speculated that TraesCS6A02G077000 (a xylanase inhibitor protein) was the primary candidate gene (named the TaXip gene). The target loci containing the three homologous genes TaXip-6A, TaXip-6B, and TaXip-6D were edited in the variety "Fielder" by clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9). Two mutant types in the T2:3 generation were obtained (aaBBDD and AAbbdd) with about 120 plants per type. The SVs of aaBBDD, AAbbdd, and WT were 31.77, 27.30, and 20.08 ml, respectively. The SVs of the aaBBDD and AAbbdd were all significantly higher than those of the wild type (WT), and the aaBBDD was significantly higher than the AAbbdd. The STs of aaBBDD, AAbbdd, and WT were 2.60, 2.24, and 2.25 min, respectively. The ST for the aaBBDD was significantly higher than that for WT and was not significantly different between WT and AAbbdd. The above results indicated that XIP in vivo can significantly affect wheat dough quality. The selection of TaXip gene should be a new strategy for developing high-quality varieties in wheat breeding programs.
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Wang Y, Liu M, Li J, Wei H, Zhang K. Experimental and in silico studies of competitive inhibition of family GH10 Aspergillus fumigatus xylanase A by Oryza sativa xylanase inhibitor protein. Int J Biol Macromol 2021; 193:1391-1399. [PMID: 34742846 DOI: 10.1016/j.ijbiomac.2021.10.201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 10/07/2021] [Accepted: 10/26/2021] [Indexed: 11/25/2022]
Abstract
The family GH10 Aspergillus fumigatus xylanase A (AfXylA10) gene, afxyla10 was cloned and recombinantly expressed in Pichia pastoris X33. The optimum temperature and pH of reAfXylA10 was 53 °C and 7.0, and Mn2+ remarkably activated the catalytic activity. The recombinant Oryza sativa xylanase inhibitor protein, rePOsXIP significantly inhibited reAfXylA10 with inhibition constant (Ki) of 177.94 nM via competitive inhibition and decreased the concentration of hydrolysate from beechwood xylan. Optimal inhibition of rePOsXIP on reAfXylA10 occurred at 45 °C for 40 min. The fluorescence of reAfXylA10 was statically quenched by rePOsXIP, indicating the formation of reAfXylA10-rePOsXIP complex during their interaction. Furthermore, molecular dynamics (MD) simulations were performed to obtain the detailed information on enzyme-inhibitor interaction. The binding free energy (ΔG) of AfXylA10-OsXIP complex was -30 ± 9 kcal/mol by MM-PBSA calculation, and the α-7 helix of OsXIP anchored in the catalytic cleft of AfXylA10 by competition with the xylan substrate. K239OsXIP stably interacted with the catalytic site E140AfXylA10 through hydrogen bond and vdW interaction. Intermolecular hydrogen bonds T104AfXylA10/V99AfXylA10-Q5OsXIP, R256AfXylA10-E235OsXIP, D155AfXylA10-Y243OsXIP and D145AfXylA10-R194OsXIP on the upper of the TIM barrel were essential for strengthening the stability of complex. Therefore, these non-covalent interactions (NCI) played key role in the interaction between AfXylA10 and OsXIP.
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Affiliation(s)
- Yuting Wang
- Key Laboratory of Marine Food Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
| | - Mingqi Liu
- Key Laboratory of Marine Food Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou 310018, China.
| | - Jiayi Li
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Huiwen Wei
- Key Laboratory of Marine Food Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
| | - Keer Zhang
- Key Laboratory of Marine Food Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
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Effect of Bran Pre-Treatment with Endoxylanase on the Characteristics of Intermediate Wheatgrass ( Thinopyrum intermedium) Bread. Foods 2021; 10:foods10071464. [PMID: 34202754 PMCID: PMC8303953 DOI: 10.3390/foods10071464] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 11/17/2022] Open
Abstract
Previous work indicated that bran removal promotes network formation in breads prepared from intermediate wheatgrass (IWG) flour. However, refinement reduces yields as well as contents of nutritionally beneficial compounds such as fiber. This study evaluated xylanase pretreatment of IWG bran as a processing option to enhance the properties of bread made with half of the original bran content. Xylanase pretreatment did not affect stickiness but significantly reduced hardness and increased specific loaf volumes compared to negative (without xylanase) and positive controls (with xylanase but without pretreatment). However, the surface of breads with pretreated bran was uneven due to structural collapse during baking. Fewer but larger gas cells were present due to pretreatment. Addition of ascorbic acid modulated these effects, but did not prevent uneven surfaces. Accessible thiol concentrations were slightly but significantly increased by xylanase pretreatment, possibly due to a less compact crumb structure. Endogenous xylanases (apparent activity 0.46 and 5.81 XU/g in flour and bran, respectively) may have been activated during the pretreatment. Moreover, Triticum aestivum xylanase inhibitor activity was also detected (193 and 410 InU/g in flour and bran). Overall, xylanase pretreatment facilitates incorporation of IWG bran into breads, but more research is needed to improve bread appearance.
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Sun J, Xu F, Lu J. Barley α-amylase/subtilisin inhibitor shows inhibitory activity against endogenous xylanase isozyme I of malted barley: A novel protein function. J Food Biochem 2020; 44:e13218. [PMID: 32236971 DOI: 10.1111/jfbc.13218] [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: 01/21/2020] [Revised: 03/06/2020] [Accepted: 03/10/2020] [Indexed: 11/29/2022]
Abstract
Mashing process had little influence on the arabinoxylan content in the finished wort. In this paper, a protein with inhibitory activity against the endogenous xylanase isozyme I (X-I) of malted barley was extracted and purified using a combination of ion-exchange and size-exclusion chromatography. The protein was identified as barley α-amylase/subtilisin inhibitor (BASI). According to the amino acid sequence analysis, BASI was completely different from the previous reported xylanase inhibitors. BASI showed dosage-dependent inhibitory activity. BASI exhibited a maximum inhibitory activity at 50°C and pH 6.0. BASI inhibited X-I as a competitive manner. PRACTICAL APPLICATIONS: A protein with inhibitory activity against the major endogenous xylanase isozyme I (X-I) of malted barley was extracted, purified, and characterized, which was identified as barley α-amylase/subtilisin inhibitor (BASI). The results help brewers to achieve a better understanding of the mechanism of arabinoxylan degradation during mashing. BASI can be used as an indicator to screen microbial xylanases. The microbial xylanases insensitive to BASI would have obvious advantages in the degradation of arabinoxylan polymers and filterability improvement during mashing.
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Affiliation(s)
- Junyong Sun
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, P.R. China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, P.R. China.,School of Biotechnology, Jiangnan University, Wuxi, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, P.R. China
| | - Feng Xu
- Wuxi Newway Biotechnology Co. Ltd., Wuxi, P.R. China
| | - Jian Lu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, P.R. China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, P.R. China.,School of Biotechnology, Jiangnan University, Wuxi, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, P.R. China
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