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Liu G, Zhang K, Gong H, Yang K, Wang X, Zhou G, Cui W, Chen Y, Yang Y. Whole genome sequencing and the lignocellulose degradation potential of Bacillus subtilis RLI2019 isolated from the intestine of termites. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:130. [PMID: 37598218 PMCID: PMC10439612 DOI: 10.1186/s13068-023-02375-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 07/25/2023] [Indexed: 08/21/2023]
Abstract
BACKGROUND Lignocellulosic biomass is the most abundant and renewable terrestrial raw material for conversion into bioproducts and biofuels. However, the low utilization efficiency of lignocellulose causes environmental pollution and resource waste, which limits the large-scale application of bioconversion. The degradation of lignocellulose by microorganisms is an efficient and cost-effective way to overcome the challenge of utilizing plant biomass resources. This work aimed to screen valuable cellulolytic bacteria, explore its molecular mechanism from genomic insights, and investigate the ability of the strain to biodegrade wheat straw. RESULTS Bacillus subtilis (B. subtilis) RLI2019 was isolated from the intestine of Reticulitermes labralis. The strain showed comprehensive enzyme activities related to lignocellulose degradation, which were estimated as 4.06, 1.97, 4.12, 0.74, and 17.61 U/mL for endoglucanase, β-glucosidase, PASC enzyme, filter paper enzyme, and xylanase, respectively. Whole genome sequencing was performed to better understand the genetic mechanism of cellulose degradation. The genome size of B. subtilis RLI2019 was 4,195,306 bp with an average GC content of 43.54%, and the sequence characteristics illustrated an extremely high probability (99.41%) as a probiotic. The genome contained 4,381 protein coding genes with an average GC content of 44.20%, of which 145 genes were classified into six carbohydrate-active enzyme (CAZyme) families and 57 subfamilies. Eight cellulose metabolism enzyme-related genes and nine hemicellulose metabolism enzyme-related genes were annotated by the CAZyme database. The starch and sucrose metabolic pathway (ko00500) was the most enriched with 46 genes in carbohydrate metabolism. B. subtilis RLI2019 was co-cultured with wheat straw for 7 days of fermentation, the contents of neutral detergent fiber, acid detergent fiber, hemicellulose, and lignin were significantly reduced by 5.8%, 10.3%, 1.0%, and 4.7%, respectively. Moreover, the wheat straw substrate exhibited 664.9 μg/mL of reducing sugars, 1.22 U/mL and 6.68 U/mL of endoglucanase and xylanase activities, respectively. Furthermore, the fiber structures were effectively disrupted, and the cellulose crystallinity was significantly reduced from 40.2% to 36.9%. CONCLUSIONS The complex diversity of CAZyme composition mainly contributed to the strong cellulolytic attribute of B. subtilis RLI2019. These findings suggest that B. subtilis RLI2019 has favorable potential for biodegradation applications, thus it can be regarded as a promising candidate bacterium for lignocellulosic biomass degradation.
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Affiliation(s)
- Gongwei Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Ke Zhang
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Hanxuan Gong
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Kaiyao Yang
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xiaoyu Wang
- Qinling Giant Panda Breeding Research Center, Shaanxi Academy of Forestry Sciences, Zhouzhi, 710402, Shaanxi, China
| | - Guangchen Zhou
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Wenyuan Cui
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Yulin Chen
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China.
| | - Yuxin Yang
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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Li Y, Fan X, Zhang H, Ai F, Jiao Y, Zhang Q, Zhang Z. Pretreatment of corn stover by torrefaction for improving reducing sugar and biohydrogen production. BIORESOURCE TECHNOLOGY 2022; 351:126905. [PMID: 35219788 DOI: 10.1016/j.biortech.2022.126905] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 02/20/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
The torrefaction pretreatment technology with different temperature varying from 160℃ to 240℃ was utilized to enhance the enzymatic saccharification and hydrogen production potential of corn stover. The composition characteristics, Crystal Intensity (CrI), reducing sugars yield and hydrogen production of the pretreated corn stover were detected to explore the torrefaction pretreatment effectiveness. Results revealed that the reducing sugar yield and hydrogen production from corn stover were improved significantly through torrefaction pretreatment, both the maximum reducing sugar yield of 427.86 ± 19 mg/g Total solid(TS) and hydrogen yield of 123.72 mL/g TS were obtained at 200 ℃, increased by 46.41% and 70.79%, respectively. The kinetic parameters from Gompertz model showed torrefaction pretreatment could shorten the lag phase time of enzymatic saccharification and hydrogen production. The reducing sugar data can be fitted well by fractal-like kinetic model and Gompertz model.
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Affiliation(s)
- Yameng Li
- Key Laboratory of New Materials and Facilities for Rural Renewable Energy, MOA of China, Henan Agricultural University, Zhengzhou 450002, China
| | - Xiaoni Fan
- Key Laboratory of New Materials and Facilities for Rural Renewable Energy, MOA of China, Henan Agricultural University, Zhengzhou 450002, China
| | - Haorui Zhang
- Key Laboratory of New Materials and Facilities for Rural Renewable Energy, MOA of China, Henan Agricultural University, Zhengzhou 450002, China
| | - Fuke Ai
- Key Laboratory of New Materials and Facilities for Rural Renewable Energy, MOA of China, Henan Agricultural University, Zhengzhou 450002, China
| | - Yinggang Jiao
- Key Laboratory of New Materials and Facilities for Rural Renewable Energy, MOA of China, Henan Agricultural University, Zhengzhou 450002, China
| | - Quanguo Zhang
- Key Laboratory of New Materials and Facilities for Rural Renewable Energy, MOA of China, Henan Agricultural University, Zhengzhou 450002, China
| | - Zhiping Zhang
- Key Laboratory of New Materials and Facilities for Rural Renewable Energy, MOA of China, Henan Agricultural University, Zhengzhou 450002, China.
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Zhang Q, Lu Z, Su C, Feng Z, Wang H, Yu J, Su W. High yielding, one-step mechano-enzymatic hydrolysis of cellulose to cellulose nanocrystals without bulk solvent. BIORESOURCE TECHNOLOGY 2021; 331:125015. [PMID: 33812135 DOI: 10.1016/j.biortech.2021.125015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 06/12/2023]
Abstract
Traditional methods of enzymatic hydrolysis of cellulose to cellulose nanocrystals (CNCs) are limited due to the low enzymatic efficiency and large amount of waste liquid. The purpose of this study is to improve the yield and production efficiency of CNCs by enzymatic hydrolysis. A one-step mechano-enzymatic hydrolysis method was developed by utilizing the synergy of wet grinding and enzymatic hydrolysis reaction to efficiently prepare CNCs. Under the optimal reaction conditions, the maximum CNCs yield of 49.3% was achieved with higher thermal stability and crystallinity index of 76.7%. Mechano-enzymatic hydrolysis followed the first order pseudo-kinetics, and fractal kinetics demonstrated that mechanical force of rotation speed affected the fractal dimensions and binding ability between substrate and enzyme. This study provides an alternative method to prepare CNCs, which can significantly avoid the use of bulk water, improve the production efficiency of CNCs and thus lower the production cost.
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Affiliation(s)
- Qihong Zhang
- National Engineering Research Center for Process Development of Active Pharmaceutical Ingredients, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, PR China
| | - Zhaohui Lu
- National Engineering Research Center for Process Development of Active Pharmaceutical Ingredients, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, PR China
| | - Chen Su
- National Engineering Research Center for Process Development of Active Pharmaceutical Ingredients, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, PR China
| | - Zongmiao Feng
- Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, PR China
| | - Hui Wang
- National Engineering Research Center for Process Development of Active Pharmaceutical Ingredients, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, PR China
| | - Jingbo Yu
- National Engineering Research Center for Process Development of Active Pharmaceutical Ingredients, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, PR China
| | - Weike Su
- National Engineering Research Center for Process Development of Active Pharmaceutical Ingredients, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, PR China; Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, PR China.
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Feng F, Zeng B, Ouyang S, Zhong Y, Chen J. Optimization of alkali-treated poplar fiber saccharification using metal ions and surfactants. Bioengineered 2020; 12:138-150. [PMID: 33350341 PMCID: PMC8806347 DOI: 10.1080/21655979.2020.1857576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
In this study, contrary to untreated poplar fiber, processing of alkali-treated poplar fiber was optimized for the enzymatic saccharification. Considering reducing sugar content as the evaluation index, pH, temperature, time, amount of enzyme, and rotational speed of shaker were standardized to optimize the sugar production by enzymatic hydrolysis. Using response surface methodology, the optimum technological condition of enzymatic hydrolysis was found to be utilizing 43 mg cellulase at 46 °C for 50 h. At this, the sugar conversion amount of NaOH or H2O2-NaOH pretreated poplar was 164.62 mg/g and 218.82 mg/g respectively. It was a corresponding increase of 446.73% or 626.75% than that of poplar fiber without a pretreatment. At a low concentration, metal ions and surfactants promoted the conversion of reducing sugar. Especially, 0.01 g/L Mn2+ and 0.50 g/L hexadecyl trimethyl ammonium bromide (CTAB) produced the best effect and increased the conversion rate of reducing sugar by 23.62% and 21.44% respectively. Also, the effect of the combination of metal ions and surfactants was better than that of a single accelerator. By improving the enzymatic process, these findings could enhance the utilization of poplar fiber for the production of reducing sugar.
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Affiliation(s)
- Fan Feng
- College of Life Science and Technology, Central South University of Forestry & Technology , Changsha, China
| | - Baiquan Zeng
- College of Life Science and Technology, Central South University of Forestry & Technology , Changsha, China
| | - Shilin Ouyang
- College of Life Science and Technology, Central South University of Forestry & Technology , Changsha, China
| | - Yanan Zhong
- College of Life Science and Technology, Central South University of Forestry & Technology , Changsha, China
| | - Jienan Chen
- Ministry of Forestry Bioethanol Research Center , Changsha, China.,Hunan Engineering Research Center for Woody Biomass Conversion , Changsha, China
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Zhang Y, Di X, Wang W, Song M, Yu Q, Wang Z, Yuan Z, Chen X, Xu H, Guo Y. Kinetic study of lipase-catalyzed esterification of furoic acid to methyl-2-furoate. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2020.107587] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Zhang Y, Di X, Xu J, Shao J, Qi W, Yuan Z. Effect of LHW, HCl, and NaOH pretreatment on enzymatic hydrolysis of sugarcane bagasse: sugar recovery and fractal-like kinetics. CHEM ENG COMMUN 2018. [DOI: 10.1080/00986445.2018.1525365] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Yu Zhang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou, China
- CAS Key Laboratory of Renewable Energy, Guangzhou, China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou, China
| | - Xiaohui Di
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou, China
- CAS Key Laboratory of Renewable Energy, Guangzhou, China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jingliang Xu
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou, China
- CAS Key Laboratory of Renewable Energy, Guangzhou, China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou, China
| | - Junchao Shao
- Guangzhou Foreign Language School, Guangzhou, China
| | - Wei Qi
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou, China
- CAS Key Laboratory of Renewable Energy, Guangzhou, China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou, China
| | - Zhenhong Yuan
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou, China
- CAS Key Laboratory of Renewable Energy, Guangzhou, China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou, China
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Westh P, Borch K, Sørensen T, Tokin R, Kari J, Badino S, Cavaleiro MA, Røjel N, Christensen S, Vesterager CS, Schiano-di-Cola C. Thermoactivation of a cellobiohydrolase. Biotechnol Bioeng 2018; 115:831-838. [PMID: 29240229 DOI: 10.1002/bit.26513] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 11/21/2017] [Accepted: 12/04/2017] [Indexed: 01/11/2023]
Abstract
We have measured activity and substrate affinity of the thermostable cellobiohydrolase, Cel7A, from Rasamsonia emersonii over a broad range of temperatures. For the wild type enzyme, which does not have a Carbohydrate Binding Module (CBM), higher temperature only led to moderately increased activity against cellulose, and we ascribed this to a pronounced, temperature induced desorption of enzyme from the substrate surface. We also tested a "high affinity" variant of R. emersonii Cel7A with a linker and CBM from a related enzyme. At room temperature, the activity of the variant was similar to the wild type, but the variant was more accelerated by temperature and about two-fold faster around 70 °C. This better thermoactivation of the high-affinity variant could not be linked to differences in stability or the catalytic process, but coincided with less desorption as temperature increased. Based on these observations and earlier reports on moderate thermoactivation of cellulases, we suggest that better cellulolytic activity at industrially relevant temperatures may be attained by engineering improved substrate affinity into enzymes that already possess good thermostability.
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Affiliation(s)
- Peter Westh
- Department of Science and Environment, INM, Universitetsvej 1, Roskilde, Denmark
| | | | - Trine Sørensen
- Department of Science and Environment, INM, Universitetsvej 1, Roskilde, Denmark
| | - Radina Tokin
- Department of Science and Environment, INM, Universitetsvej 1, Roskilde, Denmark
| | - Jeppe Kari
- Department of Science and Environment, INM, Universitetsvej 1, Roskilde, Denmark
| | - Silke Badino
- Department of Science and Environment, INM, Universitetsvej 1, Roskilde, Denmark
| | | | - Nanna Røjel
- Department of Science and Environment, INM, Universitetsvej 1, Roskilde, Denmark
| | - Stefan Christensen
- Department of Science and Environment, INM, Universitetsvej 1, Roskilde, Denmark
| | - Cynthia S Vesterager
- Department of Science and Environment, INM, Universitetsvej 1, Roskilde, Denmark
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Sørensen TH, Cruys-Bagger N, Windahl MS, Badino SF, Borch K, Westh P. Temperature Effects on Kinetic Parameters and Substrate Affinity of Cel7A Cellobiohydrolases. J Biol Chem 2015; 290:22193-202. [PMID: 26183777 DOI: 10.1074/jbc.m115.658930] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Indexed: 11/06/2022] Open
Abstract
We measured hydrolytic rates of four purified cellulases in small increments of temperature (10-50 °C) and substrate loads (0-100 g/liter) and analyzed the data by a steady state kinetic model that accounts for the processive mechanism. We used wild type cellobiohydrolases (Cel7A) from mesophilic Hypocrea jecorina and thermophilic Rasamsonia emersonii and two variants of these enzymes designed to elucidate the role of the carbohydrate binding module (CBM). We consistently found that the maximal rate increased strongly with temperature, whereas the affinity for the insoluble substrate decreased, and as a result, the effect of temperature depended strongly on the substrate load. Thus, temperature had little or no effect on the hydrolytic rate in dilute substrate suspensions, whereas strong temperature activation (Q10 values up to 2.6) was observed at saturating substrate loads. The CBM had a dual effect on the activity. On one hand, it diminished the tendency of heat-induced desorption, but on the other hand, it had a pronounced negative effect on the maximal rate, which was 2-fold larger in variants without CBM throughout the investigated temperature range. We conclude that although the CBM is beneficial for affinity it slows down the catalytic process. Cel7A from the thermophilic organism was moderately more activated by temperature than the mesophilic analog. This is in accord with general theories on enzyme temperature adaptation and possibly relevant information for the selection of technical cellulases.
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Affiliation(s)
- Trine Holst Sørensen
- From Roskilde University, Nature, Systems, and Models, Research Unit for Functional Biomaterials, 1 Universitetsvej, Building 28, DK-4000 Roskilde, Denmark and
| | - Nicolaj Cruys-Bagger
- From Roskilde University, Nature, Systems, and Models, Research Unit for Functional Biomaterials, 1 Universitetsvej, Building 28, DK-4000 Roskilde, Denmark and
| | - Michael Skovbo Windahl
- From Roskilde University, Nature, Systems, and Models, Research Unit for Functional Biomaterials, 1 Universitetsvej, Building 28, DK-4000 Roskilde, Denmark and Novozymes A/S, Krogshøjvej 36, DK-2880 Bagsværd, Denmark
| | - Silke Flindt Badino
- From Roskilde University, Nature, Systems, and Models, Research Unit for Functional Biomaterials, 1 Universitetsvej, Building 28, DK-4000 Roskilde, Denmark and Novozymes A/S, Krogshøjvej 36, DK-2880 Bagsværd, Denmark
| | - Kim Borch
- Novozymes A/S, Krogshøjvej 36, DK-2880 Bagsværd, Denmark
| | - Peter Westh
- From Roskilde University, Nature, Systems, and Models, Research Unit for Functional Biomaterials, 1 Universitetsvej, Building 28, DK-4000 Roskilde, Denmark and
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Kansou K, Buléon A, Gérard C, Rolland-Sabaté A. Amylolysis of maize mutant starches described with a fractal-like kinetics model. Carbohydr Polym 2015; 123:266-74. [DOI: 10.1016/j.carbpol.2015.01.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 01/12/2015] [Accepted: 01/15/2015] [Indexed: 11/26/2022]
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Peng X, Meng XG, Mi C, Liao XH. Hydrolysis of cellobiose to monosaccharide catalyzed by functional Lanthanum(iii) metallomicelle. RSC Adv 2015. [DOI: 10.1039/c4ra14521f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cellobiose could be effectively hydrolyzed to monosaccharide (glucose, fructose and 1,6-anhydroglucose) by the catalysis of metallomicelle La(DMBO)2under mild conditions.
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Affiliation(s)
- Xiao Peng
- Key Laboratory of Green Chemistry and Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu
| | - Xiang-Guang Meng
- Key Laboratory of Green Chemistry and Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu
| | - Chun Mi
- Key Laboratory of Green Chemistry and Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu
| | - Xiao-Hong Liao
- Key Laboratory of Green Chemistry and Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu
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