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Liu C, Choi B, Efimova E, Nygård Y, Santala S. Enhanced upgrading of lignocellulosic substrates by coculture of Saccharomyces cerevisiae and Acinetobacter baylyi ADP1. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:61. [PMID: 38711153 DOI: 10.1186/s13068-024-02510-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 04/23/2024] [Indexed: 05/08/2024]
Abstract
BACKGROUND Lignocellulosic biomass as feedstock has a huge potential for biochemical production. Still, efficient utilization of hydrolysates derived from lignocellulose is challenged by their complex and heterogeneous composition and the presence of inhibitory compounds, such as furan aldehydes. Using microbial consortia where two specialized microbes complement each other could serve as a potential approach to improve the efficiency of lignocellulosic biomass upgrading. RESULTS This study describes the simultaneous inhibitor detoxification and production of lactic acid and wax esters from a synthetic lignocellulosic hydrolysate by a defined coculture of engineered Saccharomyces cerevisiae and Acinetobacter baylyi ADP1. A. baylyi ADP1 showed efficient bioconversion of furan aldehydes present in the hydrolysate, namely furfural and 5-hydroxymethylfurfural, and did not compete for substrates with S. cerevisiae, highlighting its potential as a coculture partner. Furthermore, the remaining carbon sources and byproducts of S. cerevisiae were directed to wax ester production by A. baylyi ADP1. The lactic acid productivity of S. cerevisiae was improved approximately 1.5-fold (to 0.41 ± 0.08 g/L/h) in the coculture with A. baylyi ADP1, compared to a monoculture of S. cerevisiae. CONCLUSION The coculture of yeast and bacterium was shown to improve the consumption of lignocellulosic substrates and the productivity of lactic acid from a synthetic lignocellulosic hydrolysate. The high detoxification capacity and the ability to produce high-value products by A. baylyi ADP1 demonstrates the strain to be a potential candidate for coculture to increase production efficiency and economics of S. cerevisiae fermentations.
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Affiliation(s)
- Changshuo Liu
- Faculty of Engineering and Natural Sciences, Tampere University, Hervanta Campus, Tampere, Finland
| | - Bohyun Choi
- Department of Life Sciences, Industrial Biotechnology, Chalmers University of Technology, Gothenburg, Sweden
| | - Elena Efimova
- Faculty of Engineering and Natural Sciences, Tampere University, Hervanta Campus, Tampere, Finland
| | - Yvonne Nygård
- Department of Life Sciences, Industrial Biotechnology, Chalmers University of Technology, Gothenburg, Sweden
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Suvi Santala
- Faculty of Engineering and Natural Sciences, Tampere University, Hervanta Campus, Tampere, Finland.
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Baugh AC, Defalco JB, Duscent-Maitland CV, Tumen-Velasquez MP, Laniohan NS, Figatner K, Hoover TR, Karls AC, Elliott KT, Neidle EL. Regulation of tricarboxylate transport and metabolism in Acinetobacter baylyi ADP1. Appl Environ Microbiol 2024; 90:e0211123. [PMID: 38289138 PMCID: PMC10880598 DOI: 10.1128/aem.02111-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 12/13/2023] [Indexed: 02/22/2024] Open
Abstract
Despite the significant presence of plant-derived tricarboxylic acids in some environments, few studies detail the bacterial metabolism of trans-aconitic acid (Taa) and tricarballylic acid (Tcb). In a soil bacterium, Acinetobacter baylyi ADP1, we discovered interrelated pathways for the consumption of Taa and Tcb. An intricate regulatory scheme tightly controls the transport and catabolism of both compounds and may reflect that they can be toxic inhibitors of the tricarboxylic acid cycle. The genes encoding two similar LysR-type transcriptional regulators, TcuR and TclR, were clustered on the chromosome with tcuA and tcuB, genes required for Tcb consumption. The genetic organization differed from that in Salmonella enterica serovar Typhimurium, in which tcuA and tcuB form an operon with a transporter gene, tcuC. In A. baylyi, tcuC was not cotranscribed with tcuAB. Rather, tcuC was cotranscribed with a gene, designated pacI, encoding an isomerase needed for Taa consumption. TcuC appears to transport Tcb and cis-aconitic acid (Caa), the presumed product of PacI-mediated periplasmic isomerization of Taa. Two operons, tcuC-pacI and tcuAB, were transcriptionally controlled by both TcuR and TclR, which have overlapping functions. We investigated the roles of the two regulators in activating transcription of both operons in response to multiple effector compounds, including Taa, Tcb, and Caa.IMPORTANCEIngestion of Taa and Tcb by grazing livestock can cause a serious metabolic disorder called grass tetany. The disorder, which results from Tcb absorption by ruminants, focuses attention on the metabolism of tricarboxylic acids. Additional interest stems from efforts to produce tricarboxylic acids as commodity chemicals. Improved understanding of bacterial enzymes and pathways for tricarboxylic acid metabolism may contribute to new biomanufacturing strategies.
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Affiliation(s)
- Alyssa C. Baugh
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - Justin B. Defalco
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | | | | | | | - Kayla Figatner
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - Timothy R. Hoover
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - Anna C. Karls
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | | | - Ellen L. Neidle
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
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Jilani SB, Olson DG. Mechanism of furfural toxicity and metabolic strategies to engineer tolerance in microbial strains. Microb Cell Fact 2023; 22:221. [PMID: 37891678 PMCID: PMC10612203 DOI: 10.1186/s12934-023-02223-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 10/05/2023] [Indexed: 10/29/2023] Open
Abstract
Lignocellulosic biomass represents a carbon neutral cheap and versatile source of carbon which can be converted to biofuels. A pretreatment step is frequently used to make the lignocellulosic carbon bioavailable for microbial metabolism. Dilute acid pretreatment at high temperature and pressure is commonly utilized to efficiently solubilize the pentose fraction by hydrolyzing the hemicellulose fibers and the process results in formation of furans-furfural and 5-hydroxymethyl furfural-and other inhibitors which are detrimental to metabolism. The presence of inhibitors in the medium reduce productivity of microbial biocatalysts and result in increased production costs. Furfural is the key furan inhibitor which acts synergistically along with other inhibitors present in the hydrolysate. In this review, the mode of furfural toxicity on microbial metabolism and metabolic strategies to increase tolerance is discussed. Shared cellular targets between furfural and acetic acid are compared followed by discussing further strategies to engineer tolerance. Finally, the possibility to use furfural as a model inhibitor of dilute acid pretreated lignocellulosic hydrolysate is discussed. The furfural tolerant strains will harbor an efficient lignocellulosic carbon to pyruvate conversion mechanism in presence of stressors in the medium. The pyruvate can be channeled to any metabolite of interest by appropriate modulation of downstream pathway of interest. The aim of this review is to emphasize the use of hydrolysate as a carbon source for bioproduction of biofuels and other compounds of industrial importance.
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Affiliation(s)
- S Bilal Jilani
- Thayer School of Engineering, Dartmouth College, 15 Thayer Drive, Hanover, NH, 03755, USA.
| | - Daniel G Olson
- Thayer School of Engineering, Dartmouth College, 15 Thayer Drive, Hanover, NH, 03755, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
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Herrmann JA, Koprowska A, Winters TJ, Villanueva N, Nikityuk VD, Pek F, Reis EM, Dominguez CZ, Davis D, McPherson E, Rocco SR, Recendez C, Difuntorum SM, Faeth K, Lopez MD, Awwad HM, Ghobashy RA, Cappiello L, Neidle EL, Quiñones-Soto S, Reams AB. Gene amplification mutations originate prior to selective stress in Acinetobacter baylyi. G3 (BETHESDA, MD.) 2023; 13:jkac327. [PMID: 36504387 PMCID: PMC9997567 DOI: 10.1093/g3journal/jkac327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 08/23/2022] [Accepted: 12/06/2022] [Indexed: 12/14/2022]
Abstract
The controversial theory of adaptive amplification states gene amplification mutations are induced by selective environments where they are enriched due to the stress caused by growth restriction on unadapted cells. We tested this theory with three independent assays using an Acinetobacter baylyi model system that exclusively selects for cat gene amplification mutants. Our results demonstrate all cat gene amplification mutant colonies arise through a multistep process. While the late steps occur during selection exposure, these mutants derive from low-level amplification mutant cells that form before growth-inhibiting selection is imposed. During selection, these partial mutants undergo multiple secondary steps generating higher amplification over several days to multiple weeks to eventually form visible high-copy amplification colonies. Based on these findings, amplification in this Acinetobacter system can be explained by a natural selection process that does not require a stress response. These findings have fundamental implications to understanding the role of growth-limiting selective environments on cancer development. We suggest duplication mutations encompassing growth factor genes may serve as new genomic biomarkers to facilitate early cancer detection and treatment, before high-copy amplification is attained.
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Affiliation(s)
- Jennifer A Herrmann
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Agata Koprowska
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Tesa J Winters
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Nancy Villanueva
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Victoria D Nikityuk
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Feini Pek
- Department of Mathematics and Statistics, California State University, Sacramento, CA 95819-6051, USA
| | - Elizabeth M Reis
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Constancia Z Dominguez
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Daniel Davis
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Eric McPherson
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Staci R Rocco
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Cynthia Recendez
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Shyla M Difuntorum
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Kelly Faeth
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Mario D Lopez
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Habeeba M Awwad
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Rola A Ghobashy
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Lauren Cappiello
- Department of Mathematics and Statistics, California State University, Sacramento, CA 95819-6051, USA
| | - Ellen L Neidle
- Department of Microbiology, University of Georgia, Athens, GA 30602-2605, USA
| | - Semarhy Quiñones-Soto
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
| | - Andrew B Reams
- Department of Biological Sciences, California State University, Sacramento, CA 95819-6077, USA
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Regulation of l- and d-Aspartate Transport and Metabolism in Acinetobacter baylyi ADP1. Appl Environ Microbiol 2022; 88:e0088322. [PMID: 35862682 PMCID: PMC9361831 DOI: 10.1128/aem.00883-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The regulated uptake and consumption of d-amino acids by bacteria remain largely unexplored, despite the physiological importance of these compounds. Unlike other characterized bacteria, such as Escherichia coli, which utilizes only l-Asp, Acinetobacter baylyi ADP1 can consume both d-Asp and l-Asp as the sole carbon or nitrogen source. As described here, two LysR-type transcriptional regulators (LTTRs), DarR and AalR, control d- and l-Asp metabolism in strain ADP1. Heterologous expression of A. baylyi proteins enabled E. coli to use d-Asp as the carbon source when either of two transporters (AspT or AspY) and a racemase (RacD) were coexpressed. A third transporter, designated AspS, was also discovered to transport Asp in ADP1. DarR and/or AalR controlled the transcription of aspT, aspY, racD, and aspA (which encodes aspartate ammonia lyase). Conserved residues in the N-terminal DNA-binding domains of both regulators likely enable them to recognize the same DNA consensus sequence (ATGC-N7-GCAT) in several operator-promoter regions. In strains lacking AalR, suppressor mutations revealed a role for the ClpAP protease in Asp metabolism. In the absence of the ClpA component of this protease, DarR can compensate for the loss of AalR. ADP1 consumed l- and d-Asn and l-Glu, but not d-Glu, as the sole carbon or nitrogen source using interrelated pathways. IMPORTANCE A regulatory scheme was revealed in which AalR responds to l-Asp and DarR responds to d-Asp, a molecule with critical signaling functions in many organisms. The RacD-mediated interconversion of these isomers causes overlap in transcriptional control in A. baylyi. Our studies improve understanding of transport and regulation and lay the foundation for determining how regulators distinguish l- and d-enantiomers. These studies are relevant for biotechnology applications, and they highlight the importance of d-amino acids as natural bacterial growth substrates.
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Baptista M, Domingues L. Kluyveromyces marxianus as a microbial cell factory for lignocellulosic biomass valorisation. Biotechnol Adv 2022; 60:108027. [PMID: 35952960 DOI: 10.1016/j.biotechadv.2022.108027] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 08/04/2022] [Accepted: 08/04/2022] [Indexed: 11/02/2022]
Abstract
The non-conventional yeast Kluyveromyces marxianus is widely used for several biotechnological applications, mainly due to its thermotolerance, high growth rate, and ability to metabolise a wide range of sugars. These cell traits are strategic for lignocellulosic biomass valorisation and strain diversity prompts the development of robust chassis, either with improved tolerance to lignocellulosic inhibitors or ethanol. This review summarises bioethanol and value-added chemicals production by K. marxianus from different lignocellulosic biomasses. Moreover, metabolic engineering and process optimization strategies developed to expand K. marxianus potential are also compiled, as well as studies reporting cell mechanisms to cope with lignocellulosic-derived inhibitors. The main lignocellulosic-based products are bioethanol, representing 71% of the reports, and xylitol, representing 17% of the reports. K. marxianus also proved to be a good chassis for lactic acid and volatile compounds production from lignocellulosic biomass, although the literature on this matter is still scarce. The increasing advances in genome editing tools and process optimization strategies will widen the K. marxianus-based portfolio products.
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Affiliation(s)
- Marlene Baptista
- CEB-Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal; LABBELS -Associate Laboratory, Braga/Guimarães, Portugal
| | - Lucília Domingues
- CEB-Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal; LABBELS -Associate Laboratory, Braga/Guimarães, Portugal.
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7
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Wang H, Peng X, Li H, Giannis A, He C. Recent Biotechnology Advances in Bio-Conversion of Lignin to Lipids by Bacterial Cultures. Front Chem 2022; 10:894593. [PMID: 35494654 PMCID: PMC9039179 DOI: 10.3389/fchem.2022.894593] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 03/28/2022] [Indexed: 12/15/2022] Open
Abstract
The complexity and recalcitrance of the lignin structure is a major barrier to its efficient utilization and commercial production of high-value products. In recent years, the “bio-funneling” transformation ability of microorganisms has provided a significant opportunity for lignin conversion and integrated biorefinery. Based on the chemical structure of lignin, this mini-review introduces the recent advances of lignin depolymerization by bacterial strains and the application of microbial lignin degradation in lipids production. Furthermore, the current challenges, future trends and perspectives for microbe-based lignin conversion to lipids are discussed.
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Affiliation(s)
- Huan Wang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, State-Local Joint Laboratory for Comprehensive Utilization of Biomass, Center for R&D of Fine Chemicals, Guizhou University, Guiyang, China
- Guizhou Industry Polytechnic College, Guiyang, China
| | - Xiaodong Peng
- Guizhou Institute of Products Quality Inspection and Testing, Guiyang, China
| | - Hu Li
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, State-Local Joint Laboratory for Comprehensive Utilization of Biomass, Center for R&D of Fine Chemicals, Guizhou University, Guiyang, China
- *Correspondence: Hu Li, ; Chao He,
| | - Apostolos Giannis
- School of Chemical and Environmental Engineering, Technical University of Crete, University Campus, Chania, Greece
| | - Chao He
- Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
- *Correspondence: Hu Li, ; Chao He,
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8
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Du C, Li Y, Xiang R, Yuan W. Formate Dehydrogenase Improves the Resistance to Formic Acid and Acetic Acid Simultaneously in Saccharomyces cerevisiae. Int J Mol Sci 2022; 23:ijms23063406. [PMID: 35328826 PMCID: PMC8954399 DOI: 10.3390/ijms23063406] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/18/2022] [Accepted: 03/19/2022] [Indexed: 01/06/2023] Open
Abstract
Bioethanol from lignocellulosic biomass is a promising and sustainable strategy to meet the energy demand and to be carbon neutral. Nevertheless, the damage of lignocellulose-derived inhibitors to microorganisms is still the main bottleneck. Developing robust strains is critical for lignocellulosic ethanol production. An evolved strain with a stronger tolerance to formate and acetate was obtained after adaptive laboratory evolution (ALE) in the formate. Transcriptional analysis was conducted to reveal the possible resistance mechanisms to weak acids, and fdh coding for formate dehydrogenase was selected as the target to verify whether it was related to resistance enhancement in Saccharomyces cerevisiae F3. Engineered S. cerevisiae FA with fdh overexpression exhibited boosted tolerance to both formate and acetate, but the resistance mechanism to formate and acetate was different. When formate exists, it breaks down by formate dehydrogenase into carbon dioxide (CO2) to relieve its inhibition. When there was acetate without formate, FDH1 converted CO2 from glucose fermentation to formate and ATP and enhanced cell viability. Together, fdh overexpression alone can improve the tolerance to both formate and acetate with a higher cell viability and ATP, which provides a novel strategy for robustness strain construction to produce lignocellulosic ethanol.
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Affiliation(s)
- Cong Du
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China; (C.D.); (Y.L.); (R.X.)
| | - Yimin Li
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China; (C.D.); (Y.L.); (R.X.)
| | - Ruijuan Xiang
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China; (C.D.); (Y.L.); (R.X.)
| | - Wenjie Yuan
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China; (C.D.); (Y.L.); (R.X.)
- Ningbo Research Institute, Dalian University of Technology, Ningbo 315000, China
- Correspondence:
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Zou L, Ouyang S, Hu Y, Zheng Z, Ouyang J. Efficient lactic acid production from dilute acid-pretreated lignocellulosic biomass by a synthetic consortium of engineered Pseudomonas putida and Bacillus coagulans. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:227. [PMID: 34838093 PMCID: PMC8627035 DOI: 10.1186/s13068-021-02078-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/16/2021] [Indexed: 05/15/2023]
Abstract
BACKGROUND Lignocellulosic biomass is an attractive and sustainable alternative to petroleum-based feedstock for the production of a range of biochemicals, and pretreatment is generally regarded as indispensable for its biorefinery. However, various inhibitors that severely hinder the growth and fermentation of microorganisms are inevitably produced during the pretreatment of lignocellulose. Presently, there are few reports on a single microorganism that can detoxify or tolerate toxic mixtures of pretreated lignocellulose hydrolysate while effectively transforming sugar components into valuable compounds. Alternatively, microbial coculture provides a simpler and more efficacious way to realize this goal by distributing metabolic functions among different specialized strains. RESULTS In this study, a novel synthetic microbial consortium, which is composed of a responsible for detoxification bacterium engineered Pseudomonas putida KT2440 and a lactic acid production specialist Bacillus coagulans NL01, was developed to directly produce lactic acid from highly toxic lignocellulosic hydrolysate. The engineered P. putida with deletion of the sugar metabolism pathway was unable to consume the major fermentable sugars of lignocellulosic hydrolysate but exhibited great tolerance to 10 g/L sodium acetate, 5 g/L levulinic acid, 10 mM furfural and HMF as well as 2 g/L monophenol compound. In addition, the engineered strain rapidly removed diverse inhibitors of real hydrolysate. The degradation rate of organic acids (acetate, levulinic acid) and the conversion rate of furan aldehyde were both 100%, and the removal rate of most monoaromatic compounds remained at approximately 90%. With detoxification using engineered P. putida for 24 h, the 30% (v/v) hydrolysate was fermented to 35.8 g/L lactic acid by B. coagulans with a lactic acid yield of 0.8 g/g total sugars. Compared with that of the single culture of B. coagulans without lactic acid production, the fermentation performance of microbial coculture was significantly improved. CONCLUSIONS The microbial coculture system constructed in this study demonstrated the strong potential of the process for the biosynthesis of valuable products from lignocellulosic hydrolysates containing high concentrations of complex inhibitors by specifically recruiting consortia of robust microorganisms with desirable characteristics and also provided a feasible and attractive method for the bioconversion of lignocellulosic biomass to other value-added biochemicals.
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Affiliation(s)
- Lihua Zou
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Shuiping Ouyang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Yueli Hu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Zhaojuan Zheng
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
- Jiangsu Province Key Laboratory of Green Biomass-Based Fuels and Chemicals, Nanjing, 210037, People's Republic of China
| | - Jia Ouyang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China.
- Jiangsu Province Key Laboratory of Green Biomass-Based Fuels and Chemicals, Nanjing, 210037, People's Republic of China.
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Chanda K, Mozumder AB, Chorei R, Gogoi RK, Prasad HK. A Lignocellulolytic Colletotrichum sp. OH with Broad-Spectrum Tolerance to Lignocellulosic Pretreatment Compounds and Derivatives and the Efficiency to Produce Hydrogen Peroxide and 5-Hydroxymethylfurfural Tolerant Cellulases. J Fungi (Basel) 2021; 7:785. [PMID: 34682207 PMCID: PMC8540663 DOI: 10.3390/jof7100785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/04/2021] [Accepted: 09/07/2021] [Indexed: 10/25/2022] Open
Abstract
Fungal endophytes are an emerging source of novel traits and biomolecules suitable for lignocellulosic biomass treatment. This work documents the toxicity tolerance of Colletotrichum sp. OH toward various lignocellulosic pretreatment-derived inhibitors. The effects of aldehydes (vanillin, p-hydroxybenzaldehyde, furfural, 5-hydroxymethylfurfural; HMF), acids (gallic, formic, levulinic, and p-hydroxybenzoic acid), phenolics (hydroquinone, p-coumaric acid), and two pretreatment chemicals (hydrogen peroxide and ionic liquid), on the mycelium growth, biomass accumulation, and lignocellulolytic enzyme activities, were tested. The reported Colletotrichum sp. OH was naturally tolerant to high concentrations of single inhibitors like HMF (IC50; 17.5 mM), levulinic acid (IC50; 29.7 mM), hydroquinone (IC50; 10.76 mM), and H2O2 (IC50; 50 mM). The lignocellulolytic enzymes displayed a wide range of single and mixed inhibitor tolerance profiles. The enzymes β-glucosidase and endoglucanase showed H2O2- and HMF-dependent activity enhancements. The enzyme β-glucosidase activity was 34% higher in 75 mM and retained 20% activity in 125 mM H2O2. Further, β-glucosidase activity increased to 24 and 32% in the presence of 17.76 and 8.8 mM HMF. This research suggests that the Colletotrichum sp. OH, or its enzymes, can be used to pretreat plant biomass, hydrolyze it, and remove inhibitory by-products.
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Affiliation(s)
| | | | | | | | - Himanshu Kishore Prasad
- Department of Life Science and Bioinformatics, Assam University, Silchar 788011, India; (K.C.); (A.B.M.); (R.C.); (R.K.G.)
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11
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Henson WR, Meyers AW, Jayakody LN, DeCapite A, Black BA, Michener WE, Johnson CW, Beckham GT. Biological upgrading of pyrolysis-derived wastewater: Engineering Pseudomonas putida for alkylphenol, furfural, and acetone catabolism and (methyl)muconic acid production. Metab Eng 2021; 68:14-25. [PMID: 34438073 DOI: 10.1016/j.ymben.2021.08.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 08/18/2021] [Accepted: 08/22/2021] [Indexed: 10/20/2022]
Abstract
While biomass-derived carbohydrates have been predominant substrates for biological production of renewable fuels, chemicals, and materials, organic waste streams are growing in prominence as potential alternative feedstocks to improve the sustainability of manufacturing processes. Catalytic fast pyrolysis (CFP) is a promising approach to generate biofuels from lignocellulosic biomass, but it generates a complex, carbon-rich, and toxic wastewater stream that is challenging to process catalytically but could be biologically upgraded to valuable co-products. In this work, we implemented modular, heterologous catabolic pathways in the Pseudomonas putida KT2440-derived EM42 strain along with the overexpression of native toxicity tolerance machinery to enable utilization of 89% (w/w) of carbon in CFP wastewater. The dmp monooxygenase and meta-cleavage pathway from Pseudomonas putida CF600 were constitutively expressed to enable utilization of phenol, cresols, 2- and 3-ethyl phenol, and methyl catechols, and the native chaperones clpB, groES, and groEL were overexpressed to improve toxicity tolerance to diverse aromatic substrates. Next, heterologous furfural and acetone utilization pathways were incorporated, and a native alcohol dehydrogenase was overexpressed to improve methanol utilization, generating reducing equivalents. All pathways (encoded by genes totaling ~30 kilobases of DNA) were combined into a single strain that can catabolize a mock CFP wastewater stream as a sole carbon source. Further engineering enabled conversion of all aromatic compounds in the mock wastewater stream to (methyl)muconates with a ~90% (mol/mol) yield. Biological upgrading of CFP wastewater as outlined in this work provides a roadmap for future applications in valorizing other heterogeneous waste streams.
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Affiliation(s)
- William R Henson
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Alex W Meyers
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Lahiru N Jayakody
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Annette DeCapite
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Brenna A Black
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - William E Michener
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Christopher W Johnson
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA.
| | - Gregg T Beckham
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA.
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12
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Challenges and opportunities in biological funneling of heterogeneous and toxic substrates beyond lignin. Curr Opin Biotechnol 2021; 73:1-13. [PMID: 34242853 DOI: 10.1016/j.copbio.2021.06.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/02/2021] [Accepted: 06/07/2021] [Indexed: 12/12/2022]
Abstract
Significant developments in the understanding and manipulation of microbial metabolism have enabled the use of engineered biological systems toward a more sustainable energy and materials economy. While developments in metabolic engineering have primarily focused on the conversion of carbohydrates, substantial opportunities exist for using these same principles to extract value from more heterogeneous and toxic waste streams, such as those derived from lignin, biomass pyrolysis, or industrial waste. Funneling heterogeneous substrates from these streams toward valuable products, termed biological funneling, presents new challenges in balancing multiple catabolic pathways competing for shared cellular resources and engineering against perturbation from toxic substrates. Solutions to many of these challenges have been explored within the field of lignin valorization. This perspective aims to extend beyond lignin to highlight the challenges and discuss opportunities for use of biological systems to upgrade previously inaccessible waste streams.
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13
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Acinetobacter baylyi ADP1-naturally competent for synthetic biology. Essays Biochem 2021; 65:309-318. [PMID: 33769448 DOI: 10.1042/ebc20200136] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/23/2021] [Accepted: 02/25/2021] [Indexed: 02/02/2023]
Abstract
Acinetobacter baylyi ADP1 is a non-pathogenic soil bacterium known for its metabolic diversity and high natural transformation and recombination efficiency. For these features, A. baylyi ADP1 has been long exploited in studying bacterial genetics and metabolism. The large pool of information generated in the fundamental studies has facilitated the development of a broad range of sophisticated and robust tools for the genome and metabolic engineering of ADP1. This mini-review outlines and describes the recent advances in ADP1 engineering and tool development, exploited in, for example, pathway and enzyme evolution, genome reduction and stabilization, and for the production of native and non-native products in both pure and rationally designed multispecies cultures. The rapidly expanding toolbox together with the unique features of A. baylyi ADP1 provide a strong base for a microbial cell factory excelling in synthetic biology applications where evolution meets rational engineering.
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14
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Arteaga JE, Cerros K, Rivera-Becerril E, Lara AR, Le Borgne S, Sigala JC. Furfural biotransformation in Acinetobacter baylyi ADP1 and Acinetobacter schindleri ACE. Biotechnol Lett 2021; 43:1043-1050. [PMID: 33590377 DOI: 10.1007/s10529-021-03094-1] [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: 05/02/2020] [Accepted: 02/03/2021] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To determine furfural biotransformation capabilities of Acinetobacter baylyi ADP1 and Acinetobacter schindleri ACE. RESULTS Acinetobacter baylyi ADP1 and A. schindleri ACE could not use furfural as sole carbon source but when acetate was used as substrate, ADP1 and ACE biotransformed 1 g furfural/l in 5 and 9 h, respectively. In both cases, the product of this biotransformation was difurfuryl-ether as shown by FT-IR and 1H and 13C NMR spectroscopy. The presence of furfural decreased the specific growth rate in acetate by 27% in ADP1 and 53% in ACE. For both strains, the MIC of furfural was 1.25 g/l. Nonetheless, ADP1 biotransformed 2 g furfural/l at a rate of 1 g/l/h in the stationary phase of growth. A transcriptional analysis of possible dehydrogenases involved in this biotransformation, identified that the areB and frmA genes were highly overexpressed after the exposure of ADP1 to furfural. The products of these genes are a benzyl-alcohol dehydrogenase and an alcohol dehydrogenase. CONCLUSIONS Acinetobacter baylyi ADP1 is a candidate for the biological detoxification of furfural, a fermentation inhibitor present in lignocellulosic hydrolysates, with the possible direct involvement of the AreB and FrmA enzymes in the process.
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Affiliation(s)
- José Eduardo Arteaga
- Posgrado en Ciencias Naturales e Ingeniería, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, 05348, Mexico City, Mexico
| | - Karina Cerros
- Posgrado en Ciencias Naturales e Ingeniería, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, 05348, Mexico City, Mexico
| | - Ernesto Rivera-Becerril
- Departamento de Ciencias Naturales, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, 05348, Mexico City, Mexico
| | - Alvaro R Lara
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana, Unidad Cuajimalpa. Av. Vasco de Quiroga 4871, Col. Santa Fe Cuajimalpa, Alcaldía Cuajimalpa, 05348, Mexico City, Mexico
| | - Sylvie Le Borgne
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana, Unidad Cuajimalpa. Av. Vasco de Quiroga 4871, Col. Santa Fe Cuajimalpa, Alcaldía Cuajimalpa, 05348, Mexico City, Mexico
| | - Juan-Carlos Sigala
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana, Unidad Cuajimalpa. Av. Vasco de Quiroga 4871, Col. Santa Fe Cuajimalpa, Alcaldía Cuajimalpa, 05348, Mexico City, Mexico.
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15
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Abstract
Biological wax esters offer a sustainable, renewable and biodegradable alternative to many fossil fuel derived chemicals including plastics and paraffins. Many species of bacteria accumulate waxes with similar structure and properties to highly desirable animal and plant waxes such as Spermaceti and Jojoba oils, the use of which is limited by resource requirements, high cost and ethical concerns. While bacterial fermentations overcome these issues, a commercially viable bacterial wax production process would require high yields and renewable, affordable feedstock to make it economically competitive and environmentally beneficial. This review describes recent progress in wax ester generation in both wild type and genetically engineered bacteria, with a focus on comparing substrates and quantifying obtained waxes. The full breadth of wax accumulating species is discussed, with emphasis on species generating high yields and utilising renewable substrates. Key areas of the field that have, thus far, received limited attention are highlighted, such as waste stream valorisation, mixed microbial cultures and efficient wax extraction, as, until effectively addressed, these will slow progress in creating commercially viable wax production methods.
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16
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Biggs BW, Bedore SR, Arvay E, Huang S, Subramanian H, McIntyre EA, Duscent-Maitland CV, Neidle EL, Tyo KEJ. Development of a genetic toolset for the highly engineerable and metabolically versatile Acinetobacter baylyi ADP1. Nucleic Acids Res 2020; 48:5169-5182. [PMID: 32246719 PMCID: PMC7229861 DOI: 10.1093/nar/gkaa167] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 02/20/2020] [Accepted: 03/04/2020] [Indexed: 01/10/2023] Open
Abstract
One primary objective of synthetic biology is to improve the sustainability of chemical manufacturing. Naturally occurring biological systems can utilize a variety of carbon sources, including waste streams that pose challenges to traditional chemical processing, such as lignin biomass, providing opportunity for remediation and valorization of these materials. Success, however, depends on identifying micro-organisms that are both metabolically versatile and engineerable. Identifying organisms with this combination of traits has been a historic hindrance. Here, we leverage the facile genetics of the metabolically versatile bacterium Acinetobacter baylyi ADP1 to create easy and rapid molecular cloning workflows, including a Cas9-based single-step marker-less and scar-less genomic integration method. In addition, we create a promoter library, ribosomal binding site (RBS) variants and test an unprecedented number of rationally integrated bacterial chromosomal protein expression sites and variants. At last, we demonstrate the utility of these tools by examining ADP1’s catabolic repression regulation, creating a strain with improved potential for lignin bioprocessing. Taken together, this work highlights ADP1 as an ideal host for a variety of sustainability and synthetic biology applications.
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Affiliation(s)
- Bradley W Biggs
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA.,Biotechnology Training Program, Northwestern University, Evanston, IL 60208, USA
| | - Stacy R Bedore
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Erika Arvay
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA.,Biotechnology Training Program, Northwestern University, Evanston, IL 60208, USA
| | - Shu Huang
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Harshith Subramanian
- Master of Science in Biotechnology Program, Northwestern University, Evanston, IL 60208, USA
| | - Emily A McIntyre
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | | | - Ellen L Neidle
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Keith E J Tyo
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA
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17
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Bhatia SK, Jagtap SS, Bedekar AA, Bhatia RK, Patel AK, Pant D, Rajesh Banu J, Rao CV, Kim YG, Yang YH. Recent developments in pretreatment technologies on lignocellulosic biomass: Effect of key parameters, technological improvements, and challenges. BIORESOURCE TECHNOLOGY 2020; 300:122724. [PMID: 31926792 DOI: 10.1016/j.biortech.2019.122724] [Citation(s) in RCA: 207] [Impact Index Per Article: 51.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/27/2019] [Accepted: 12/30/2019] [Indexed: 05/12/2023]
Abstract
Lignocellulosic biomass is an inexpensive renewable source that can be used to produce biofuels and bioproducts. The recalcitrance nature of biomass hampers polysaccharide accessibility for enzymes and microbes. Several pretreatment methods have been developed for the conversion of lignocellulosic biomass into value-added products. However, these pretreatment methods also produce a wide range of secondary compounds, which are inhibitory to enzymes and microorganisms. The selection of an effective and efficient pretreatment method discussed in the review and its process optimization can significantly reduce the production of inhibitory compounds and may lead to enhanced production of fermentable sugars and biochemicals. Moreover, evolutionary and genetic engineering approaches are being used for the improvement of microbial tolerance towards inhibitors. Advancements in pretreatment and detoxification technologies may help to increase the productivity of lignocellulose-based biorefinery. In this review, we discuss the recent advancements in lignocellulosic biomass pretreatment technologies and strategies for the removal of inhibitors.
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Affiliation(s)
- Shashi Kant Bhatia
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea; Institute for Ubiquitous Information Technology and Application, Konkuk University, Seoul 05029, Republic of Korea
| | - Sujit Sadashiv Jagtap
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave, Urbana, IL 61801, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave, Urbana, IL 61801, USA
| | - Ashwini Ashok Bedekar
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave, Urbana, IL 61801, USA
| | - Ravi Kant Bhatia
- Department of Biotechnology, Himachal Pradesh University, Summer Hill-171005 (H.P), India
| | - Anil Kumar Patel
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Deepak Pant
- Department of Chemistry, Central University of Haryana, Mahendragarh, Haryana 123031, India
| | - J Rajesh Banu
- Department of Civil Engineering, Anna University Regional Campus, Tirunelveli, India
| | - Christopher V Rao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave, Urbana, IL 61801, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave, Urbana, IL 61801, USA
| | - Yun-Gon Kim
- Department of Chemical Engineering, Soongsil University, 06978 Seoul, Republic of Korea
| | - Yung-Hun Yang
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea; Institute for Ubiquitous Information Technology and Application, Konkuk University, Seoul 05029, Republic of Korea.
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18
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Engineering CatM, a LysR-Type Transcriptional Regulator, to Respond Synergistically to Two Effectors. Genes (Basel) 2019; 10:genes10060421. [PMID: 31159259 PMCID: PMC6628147 DOI: 10.3390/genes10060421] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 05/24/2019] [Accepted: 05/30/2019] [Indexed: 11/19/2022] Open
Abstract
The simultaneous response of one transcriptional regulator to different effectors remains largely unexplored. Nevertheless, such interactions can substantially impact gene expression by rapidly integrating cellular signals and by expanding the range of transcriptional responses. In this study, similarities between paralogs were exploited to engineer novel responses in CatM, a regulator that controls benzoate degradation in Acinetobacter baylyi ADP1. One goal was to improve understanding of how its paralog, BenM, activates transcription in response to two compounds (cis,cis-muconate and benzoate) at levels significantly greater than with either alone. Despite the overlapping functions of BenM and CatM, which regulate many of the same ben and cat genes, CatM normally responds only to cis,cis-muconate. Using domain swapping and site-directed amino acid replacements, CatM variants were generated and assessed for the ability to activate transcription. To create a variant that responds synergistically to both effectors required alteration of both the effector-binding region and the DNA-binding domain. These studies help define the interconnected roles of protein domains and extend understanding of LysR-type proteins, the largest family of transcriptional regulators in bacteria. Additionally, renewed interest in the modular functionality of transcription factors stems from their potential use as biosensors.
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