1
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Liu J, Hu Y, Gu W, Lan H, Zhang Z, Jiang L, Xu X. Research progress on the application of cell-free synthesis systems for enzymatic processes. Crit Rev Biotechnol 2023; 43:938-955. [PMID: 35994247 DOI: 10.1080/07388551.2022.2090314] [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: 10/13/2021] [Revised: 02/24/2022] [Accepted: 04/09/2022] [Indexed: 11/03/2022]
Abstract
Cell-free synthesis systems can complete the transcription and translation process in vitro to produce complex proteins that are difficult to be expressed in traditional cell-based systems. Such systems also can be used for the assembly of efficient localized multienzyme cascades to synthesize products that are toxic to cells. Cell-free synthesis systems provide a simpler and faster engineering solution than living cells, allowing unprecedented design freedom. This paper reviews the latest progress on the application of cell-free synthesis systems in the field of enzymatic catalysis, including cell-free protein synthesis and cell-free metabolic engineering. In cell-free protein synthesis: complex proteins, toxic proteins, membrane proteins, and artificial proteins containing non-natural amino acids can be easily synthesized by directly controlling the reaction conditions in the cell-free system. In cell-free metabolic engineering, the synthesis of desired products can be made more specific and efficient by designing metabolic pathways and screening biocatalysts based on purified enzymes or crude extracts. Through the combination of cell-free synthesis systems and emerging technologies, such as: synthetic biology, microfluidic control, cofactor regeneration, and artificial scaffolds, we will be able to build increasingly complex biomolecule systems. In the next few years, these technologies are expected to mature and reach industrialization, providing innovative platforms for a wide range of biotechnological applications.
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Affiliation(s)
- Jie Liu
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China
| | - Yongqi Hu
- School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Wanyi Gu
- School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Haiquan Lan
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China
| | - Zhidong Zhang
- Institute of Microbiology, Xinjiang Academy of Agricultural Sciences, Urumqi, China
| | - Ling Jiang
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
| | - Xian Xu
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China
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2
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Song S, Huang L, Zhou P. Efficient H2 production in a ZnFe2O4/g-C3N4 photo-cathode single-chamber microbial electrolysis cell. Appl Microbiol Biotechnol 2022; 107:391-404. [DOI: 10.1007/s00253-022-12293-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 10/13/2022] [Accepted: 11/15/2022] [Indexed: 11/23/2022]
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3
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Liang Y, Luo J, Yang C, Guo S, Zhang B, Chen F, Su K, Zhang Y, Dong Y, Wang Z, Fu H, Sui G, Wang P. Directed evolution of the PobR allosteric transcription factor to generate a biosensor for 4-hydroxymandelic acid. World J Microbiol Biotechnol 2022; 38:104. [PMID: 35501522 DOI: 10.1007/s11274-022-03286-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Accepted: 04/12/2022] [Indexed: 10/18/2022]
Abstract
Hydroxy-mandelic acid (HMA) is widely applied in pharmaceuticals, food and cosmetics. In this study, we aimed to develop an allosteric transcription factors (aTFs) based biosensor for HMA. PobR, an aTF for HMA analog 4-hydroxybenzoic acid, was used to alter its selectivity and create novel aTFs responsive to HMA by directed evolution. We established a PobR mutant library with a capacity of 550,000 mutants using error-prone PCR and Megawhop PCR. Through our screening, two mutants were obtained with responsiveness to HMA. Analysis of each missense mutation indicating residues 122-126 were involved in its PobR ligand specificity. These results showed the effectiveness of directed evolution in switching the ligand specificity of a biosensor and improving HMA production.
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Affiliation(s)
- YaoYao Liang
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,Key Laboratory for Enzymes and Enzyme-Like Material Engineering of Heilongjiang, Harbin, Heilongjiang, 150040, People's Republic of China
| | - Juan Luo
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Chenhao Yang
- Aulin College, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Shuning Guo
- Aulin College, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Bowen Zhang
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Fengqianrui Chen
- Aulin College, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Kairui Su
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Yulong Zhang
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Yi Dong
- Aulin College, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Zhihao Wang
- Aulin College, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Hongda Fu
- NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Guangchao Sui
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China. .,Aulin College, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China. .,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China. .,Northeast Forestry University, No. 26 Hexing Road, Harbin, 150000, People's Republic of China.
| | - Pengchao Wang
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China. .,Aulin College, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China. .,NEFU-China iGEM Team, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China. .,Key Laboratory for Enzymes and Enzyme-Like Material Engineering of Heilongjiang, Harbin, Heilongjiang, 150040, People's Republic of China. .,Northeast Forestry University, No. 26 Hexing Road, Harbin, 150000, People's Republic of China.
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4
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Webb JP, Paiva AC, Rossoni L, Alstrom-Moore A, Springthorpe V, Vaud S, Yeh V, Minde DP, Langer S, Walker H, Hounslow A, Nielsen DR, Larson T, Lilley K, Stephens G, Thomas GH, Bonev BB, Kelly DJ, Conradie A, Green J. Multi-omic based production strain improvement (MOBpsi) for bio-manufacturing of toxic chemicals. Metab Eng 2022; 72:133-149. [DOI: 10.1016/j.ymben.2022.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 02/11/2022] [Accepted: 03/08/2022] [Indexed: 11/25/2022]
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5
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Wang H, Liu Y, Cheng X, Zhang Y, Li S, Wang X, Xiang W. Titer improvement of milbemycins via coordinating metabolic competition and transcriptional co-activation controlled by SARP family regulator in Streptomyces bingchenggensis. Biotechnol Bioeng 2022; 119:1252-1263. [PMID: 35084043 DOI: 10.1002/bit.28044] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 12/30/2021] [Accepted: 01/17/2022] [Indexed: 11/09/2022]
Abstract
Streptomyces bingchenggensis is a promising producer of milbemycins (MILs), the macrolide pesticide used widely in agriculture. The relationship between different biosynthetic gene clusters (BGCs) and the MIL BGC remains unclear, which hinders the precise metabolic engineering of S. bingchenggensis for titer improvement. To address this issue, this study discovered the regulatory function of a previously unidentified regulator KelR on a type-II polyketide BGC, MIL BGC and two other BGCs, and caused titer improvement. First, a type II polyketide synthase (PKS) gene cluster kel with a bidirectional effect on MIL biosynthesis was found using transcriptome analysis. A Streptomyces antibiotic regulatory protein (SARP) family regulator KelR from the kel cluster was then characterized as an activator of several BGCs including mil and kel clusters. Metabolic competition between mil and kel clusters at the late fermentation stage was confirmed. Finally, KelR and those BGCs were manipulated in S. bingchenggensis, which led to a 71.7% titer improvement of MIL A3/A4 to 4058.2±71.0 mg/L. This research deciphered the regulatory function of a previously unidentified regulatory protein KelR on several BGCs including mil in S. bingchenggensis and provided an example of coordinating metabolic competition and co-regulation for titer improvement of secondary metabolites. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Haiyan Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Yuqing Liu
- School of Life Science, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, China
| | - Xu Cheng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Yanyan Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Shanshan Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Xiangjing Wang
- School of Life Science, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, China
| | - Wensheng Xiang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China.,School of Life Science, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, China
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6
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Pujari I, Thomas A, Sankar Babu V. Native and non-native host assessment towards metabolic pathway reconstructions of plant natural products. ACTA ACUST UNITED AC 2021; 30:e00619. [PMID: 33996523 PMCID: PMC8091882 DOI: 10.1016/j.btre.2021.e00619] [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] [Received: 09/14/2020] [Revised: 04/05/2021] [Accepted: 04/11/2021] [Indexed: 11/16/2022]
Abstract
Plant metabolic networks are highly complex. Engineering the phytochemical pathways fully in heterologous hosts is challenging. Single plant cells with amplified multiple fission enable homogeneity. Homogeneity and high cell division rate can facilitate stable product scale-up.
Plant-based biopreparations are reasonably priced and are devoid of viral, prion and endotoxin contaminants. However, synthesizing these natural plant products by chemical methods is quite expensive. The structural complexity of plant-derived natural products poses a challenge for chemical synthesis at a commercial scale. Failure of commercial-scale synthesis is the chief reason why metabolic reconstructions in heterologous hosts are inevitable. This review discusses plant metabolite pathway reconstructions experimented in various heterologous hosts, and the inherent challenges involved. Plants as native hosts possess enhanced post-translational modification ability, along with rigorous gene edits, unlike microbes. To achieve a high yield of metabolites in plants, increased cell division rate is one of the requisites. This improved cell division rate will promote cellular homogeneity. Incorporation and maintenance of plant cell synchrony, in turn, can program stable product scale-up.
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Affiliation(s)
- Ipsita Pujari
- Department of Plant Sciences, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Abitha Thomas
- Department of Plant Sciences, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Vidhu Sankar Babu
- Department of Plant Sciences, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
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Santoscoy MC, Jarboe LR. A systematic framework for using membrane metrics for strain engineering. Metab Eng 2021; 66:98-113. [PMID: 33813035 DOI: 10.1016/j.ymben.2021.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 03/14/2021] [Accepted: 03/15/2021] [Indexed: 11/20/2022]
Abstract
The cell membrane plays a central role in the fitness and performance of microbial cell factories and therefore it is an attractive engineering target. The goal of this work is to develop a systematic framework for identifying membrane features for use as engineering targets. The metrics that describe the composition of the membrane can be visualized as "knobs" that modulate various "outcomes", such as physical properties of the membrane and metabolic activity in the form of growth and productivity, with these relationships varying depending on the condition. We generated a set of strains with altered membrane lipid composition via expression of des, fabA and fabB and performed a rigorous characterization of these knobs and outcomes across several individual inhibitory conditions. Here, the knobs are the relative abundance of unsaturated lipids and lipids containing cyclic rings; the average lipid length, and the ratio of linear and non-linear lipids (L/nL ratio). The outcomes are membrane permeability, hydrophobicity, fluidity, and specific growth rate. This characterization identified significant correlations between knobs and outcomes that were specific to individual inhibitors, but also were significant across all tested conditions. For example, across all conditions, the L/nL ratio is positively correlated with the cell surface hydrophobicity, and the average lipid length is positively correlated with specific growth rate. A subsequent analysis of the data with the individual inhibitors identified pairs of lipid metrics and membrane properties that were predicted to impact cell growth in seven modeled scenarios with two or more inhibitors. The L/nL ratio and the membrane hydrophobicity were predicted to impact cell growth with the highest frequency. We experimentally validated this prediction in the combined condition of 42 °C, 2.5 mM furfural and 2% v/v ethanol in minimal media. Membrane hydrophobicity was confirmed to be a significant predictor of ethanol production. This work demonstrates that membrane physical properties can be used to predict the performance of biocatalysts in single and multiple inhibitory conditions, and possibly as an engineering target. In this manner, membrane properties can possibly be used as screening or selection metrics for library- or evolution-based strain engineering.
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Affiliation(s)
- Miguel C Santoscoy
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Laura R Jarboe
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA.
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8
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Chen Y, Boggess EE, Ocasio ER, Warner A, Kerns L, Drapal V, Gossling C, Ross W, Gourse RL, Shao Z, Dickerson J, Mansell TJ, Jarboe LR. Reverse engineering of fatty acid-tolerant Escherichia coli identifies design strategies for robust microbial cell factories. Metab Eng 2020; 61:120-130. [PMID: 32474056 DOI: 10.1016/j.ymben.2020.05.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 02/05/2020] [Accepted: 05/02/2020] [Indexed: 10/24/2022]
Abstract
Adaptive laboratory evolution is often used to improve the performance of microbial cell factories. Reverse engineering of evolved strains enables learning and subsequent incorporation of novel design strategies via the design-build-test-learn cycle. Here, we reverse engineer a strain of Escherichia coli previously evolved for increased tolerance of octanoic acid (C8), an attractive biorenewable chemical, resulting in increased C8 production, increased butanol tolerance, and altered membrane properties. Here, evolution was determined to have occurred first through the restoration of WaaG activity, involved in the production of lipopolysaccharides, then an amino acid change in RpoC, a subunit of RNA polymerase, and finally mutation of the BasS-BasR two component system. All three mutations were required in order to reproduce the increased growth rate in the presence of 20 mM C8 and increased cell surface hydrophobicity; the WaaG and RpoC mutations both contributed to increased C8 titers, with the RpoC mutation appearing to be the major driver of this effect. Each of these mutations contributed to changes in the cell membrane. Increased membrane integrity and rigidity and decreased abundance of extracellular polymeric substances can be attributed to the restoration of WaaG. The increase in average lipid tail length can be attributed to the RpoCH419P mutation, which also confers tolerance to other industrially-relevant inhibitors, such as furfural, vanillin and n-butanol. The RpoCH419P mutation may impact binding or function of the stringent response alarmone ppGpp to RpoC site 1. Each of these mutations provides novel strategies for engineering microbial robustness, particularly at the level of the microbial cell membrane.
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Affiliation(s)
- Yingxi Chen
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Erin E Boggess
- Department of Electrical and Computer Engineering, Iowa State University, Ames, IA, 50011, USA; Bioinformatics & Computational Biology Graduate Program, Iowa State University, Ames, IA, 50011, USA
| | - Efrain Rodriguez Ocasio
- NSF Center for Biorenewable Chemicals (CBiRC) Research Experience for Undergraduates, Ames, IA, 50011, USA; Industrial Biotechnology Program, University of Puerto Rico Mayagüez, 00681, Puerto Rico
| | - Aric Warner
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, 50011, USA
| | - Lucas Kerns
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Victoria Drapal
- NSF Center for Biorenewable Chemicals (CBiRC) Research Experience for Undergraduates, Ames, IA, 50011, USA; Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68508, USA
| | - Chloe Gossling
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Wilma Ross
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Richard L Gourse
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Zengyi Shao
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA; Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, 50011, USA
| | - Julie Dickerson
- Department of Electrical and Computer Engineering, Iowa State University, Ames, IA, 50011, USA; Bioinformatics & Computational Biology Graduate Program, Iowa State University, Ames, IA, 50011, USA
| | - Thomas J Mansell
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA; Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, 50011, USA.
| | - Laura R Jarboe
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA; Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, 50011, USA.
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9
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Minazzato G, Gasparrini M, Amici A, Cianci M, Mazzola F, Orsomando G, Sorci L, Raffaelli N. Functional Characterization of COG1713 (YqeK) as a Novel Diadenosine Tetraphosphate Hydrolase Family. J Bacteriol 2020; 202:e00053-20. [PMID: 32152217 PMCID: PMC7186459 DOI: 10.1128/jb.00053-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 03/03/2020] [Indexed: 12/29/2022] Open
Abstract
Diadenosine tetraphosphate (Ap4A) is a dinucleotide found in both prokaryotes and eukaryotes. In bacteria, its cellular levels increase following exposure to various stress signals and stimuli, and its accumulation is generally correlated with increased sensitivity to a stressor(s), decreased pathogenicity, and enhanced antibiotic susceptibility. Ap4A is produced as a by-product of tRNA aminoacylation, and is cleaved to ADP molecules by hydrolases of the ApaH and Nudix families and/or by specific phosphorylases. Here, considering evidence that the recombinant protein YqeK from Staphylococcus aureus copurified with ADP, and aided by thermal shift and kinetic analyses, we identified the YqeK family of proteins (COG1713) as an unprecedented class of symmetrically cleaving Ap4A hydrolases. We validated the functional assignment by confirming the ability of YqeK to affect in vivo levels of Ap4A in B. subtilis YqeK shows a catalytic efficiency toward Ap4A similar to that of the symmetrically cleaving Ap4A hydrolases of the known ApaH family, although it displays a distinct fold that is typical of proteins of the HD domain superfamily harboring a diiron cluster. Analysis of the available 3D structures of three members of the YqeK family provided hints to the mode of substrate binding. Phylogenetic analysis revealed the occurrence of YqeK proteins in a consistent group of Gram-positive bacteria that lack ApaH enzymes. Comparative genomics highlighted that yqeK and apaH genes share a similar genomic context, where they are frequently found in operons involved in integrated responses to stress signals.IMPORTANCE Elevation of Ap4A level in bacteria is associated with increased sensitivity to heat and oxidative stress, reduced antibiotic tolerance, and decreased pathogenicity. ApaH is the major Ap4A hydrolase in gamma- and betaproteobacteria and has been recently proposed as a novel target to weaken the bacterial resistance to antibiotics. Here, we identified the orphan YqeK protein family (COG1713) as a highly efficient Ap4A hydrolase family, with members distributed in a consistent group of bacterial species that lack the ApaH enzyme. Among them are the pathogens Staphylococcus aureus, Streptococcus pneumoniae, and Mycoplasma pneumoniae By identifying the player contributing to Ap4A homeostasis in these bacteria, we disclose a novel target to develop innovative antibacterial strategies.
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Affiliation(s)
- Gabriele Minazzato
- Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Massimiliano Gasparrini
- Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Adolfo Amici
- Department of Clinical Sciences DISCO, Section of Biochemistry, Polytechnic University of Marche, Ancona, Italy
| | - Michele Cianci
- Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Francesca Mazzola
- Department of Clinical Sciences DISCO, Section of Biochemistry, Polytechnic University of Marche, Ancona, Italy
| | - Giuseppe Orsomando
- Department of Clinical Sciences DISCO, Section of Biochemistry, Polytechnic University of Marche, Ancona, Italy
| | - Leonardo Sorci
- Department of Materials, Environmental Sciences and Urban Planning, Division of Bioinformatics and Biochemistry, Polytechnic University of Marche, Ancona, Italy
| | - Nadia Raffaelli
- Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
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10
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Fabian BK, Tetu SG, Paulsen IT. Application of Transposon Insertion Sequencing to Agricultural Science. FRONTIERS IN PLANT SCIENCE 2020; 11:291. [PMID: 32256512 PMCID: PMC7093568 DOI: 10.3389/fpls.2020.00291] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 02/26/2020] [Indexed: 06/11/2023]
Abstract
Many plant-associated bacteria have the ability to positively affect plant growth and there is growing interest in utilizing such bacteria in agricultural settings to reduce reliance on pesticides and fertilizers. However, our capacity to utilize microbes in this way is currently limited due to patchy understanding of bacterial-plant interactions at a molecular level. Traditional methods of studying molecular interactions have sought to characterize the function of one gene at a time, but the slow pace of this work means the functions of the vast majority of bacterial genes remain unknown or poorly understood. New approaches to improve and speed up investigations into the functions of bacterial genes in agricultural systems will facilitate efforts to optimize microbial communities and develop microbe-based products. Techniques enabling high-throughput gene functional analysis, such as transposon insertion sequencing analyses, have great potential to be widely applied to determine key aspects of plant-bacterial interactions. Transposon insertion sequencing combines saturation transposon mutagenesis and high-throughput sequencing to simultaneously investigate the function of all the non-essential genes in a bacterial genome. This technique can be used for both in vitro and in vivo studies to identify genes involved in microbe-plant interactions, stress tolerance and pathogen virulence. The information provided by such investigations will rapidly accelerate the rate of bacterial gene functional determination and provide insights into the genes and pathways that underlie biotic interactions, metabolism, and survival of agriculturally relevant bacteria. This knowledge could be used to select the most appropriate plant growth promoting bacteria for a specific set of conditions, formulating crop inoculants, or developing crop protection products. This review provides an overview of transposon insertion sequencing, outlines how this approach has been applied to study plant-associated bacteria, and proposes new applications of these techniques for the benefit of agriculture.
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Affiliation(s)
- Belinda K. Fabian
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, NSW, Australia
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Sasha G. Tetu
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, NSW, Australia
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Ian T. Paulsen
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, NSW, Australia
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
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11
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Vavricka CJ, Hasunuma T, Kondo A. Dynamic Metabolomics for Engineering Biology: Accelerating Learning Cycles for Bioproduction. Trends Biotechnol 2020; 38:68-82. [DOI: 10.1016/j.tibtech.2019.07.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 07/18/2019] [Accepted: 07/19/2019] [Indexed: 12/15/2022]
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12
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Lessons in Membrane Engineering for Octanoic Acid Production from Environmental Escherichia coli Isolates. Appl Environ Microbiol 2018; 84:AEM.01285-18. [PMID: 30030228 DOI: 10.1128/aem.01285-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 07/10/2018] [Indexed: 01/01/2023] Open
Abstract
Fermentative production of many attractive biorenewable fuels and chemicals is limited by product toxicity in the form of damage to the microbial cell membrane. Metabolic engineering of the production organism can help mitigate this problem, but there is a need for identification and prioritization of the most effective engineering targets. Here, we use a set of previously characterized environmental Escherichia coli isolates with high tolerance and production of octanoic acid, a model membrane-damaging biorenewable product, as a case study for identifying and prioritizing membrane engineering strategies. This characterization identified differences in the membrane lipid composition, fluidity, integrity, and cell surface hydrophobicity from those of the lab strain MG1655. Consistent with previous publications, decreased membrane fluidity was associated with increased fatty acid production ability. Maintenance of high membrane integrity or longer membrane lipids seemed to be of less importance than fluidity. Cell surface hydrophobicity was also directly associated with fatty acid production titers, with the strength of this association demonstrated by plasmid-based expression of the multiple stress resistance outer membrane protein BhsA. This expression of bhsA was effective in altering hydrophobicity, but the direction and magnitude of the change differed between strains. Thus, additional strategies are needed to reliably engineer cell surface hydrophobicity. This work demonstrates the ability of environmental microbiological studies to impact the metabolic engineering design-build-test-learn cycle and possibly increase the economic viability of fermentative bioprocesses.IMPORTANCE The production of bulk fuels and chemicals in a bio-based fermentation process requires high product titers. This is often difficult to achieve, because many of the target molecules damage the membrane of the microbial cell factory. Engineering the composition of the membrane in order to decrease its vulnerability to this damage has proven to be an effective strategy for improving bioproduction, but additional strategies and engineering targets are needed. Here, we studied a small set of environmental Escherichia coli isolates that have higher production titers of octanoic acid, a model biorenewable chemical, than those of the lab strain MG1655. We found that membrane fluidity and cell surface hydrophobicity are strongly associated with improved octanoic acid production. Fewer genetic modification strategies have been demonstrated for tuning hydrophobicity relative to fluidity, leading to the conclusion that there is a need for expanding hydrophobicity engineering strategies in E. coli.
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