1
|
Kim K, Choe D, Cho S, Palsson B, Cho BK. Reduction-to-synthesis: the dominant approach to genome-scale synthetic biology. Trends Biotechnol 2024; 42:1048-1063. [PMID: 38423803 DOI: 10.1016/j.tibtech.2024.02.008] [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: 12/14/2023] [Revised: 02/09/2024] [Accepted: 02/12/2024] [Indexed: 03/02/2024]
Abstract
Advances in systems and synthetic biology have propelled the construction of reduced bacterial genomes. Genome reduction was initially focused on exploring properties of minimal genomes, but more recently it has been deployed as an engineering strategy to enhance strain performance. This review provides the latest updates on reduced genomes, focusing on dual-track approaches of top-down reduction and bottom-up synthesis for their construction. Using cases from studies that are based on established industrial workhorse strains, we discuss the construction of a series of synthetic phenotypes that are candidates for biotechnological applications. Finally, we address the possible uses of reduced genomes for biotechnological applications and the needed future research directions that may ultimately lead to the total synthesis of rationally designed genomes.
Collapse
Affiliation(s)
- Kangsan Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea; KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Donghui Choe
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
| | - Suhyung Cho
- KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Bernhard Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA; Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Kongens, Lyngby, Denmark
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea; KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea; Graduate School of Engineering Biology, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.
| |
Collapse
|
2
|
Gao H, Wang Y, Huang Z, Yu F, Hu X, Ning D, Xu X. Development of Leptolyngbya sp. BL0902 into a model organism for synthetic biological research in filamentous cyanobacteria. Front Microbiol 2024; 15:1409771. [PMID: 39104590 PMCID: PMC11298460 DOI: 10.3389/fmicb.2024.1409771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/10/2024] [Indexed: 08/07/2024] Open
Abstract
Cyanobacteria have great potential in CO2-based bio-manufacturing and synthetic biological studies. The filamentous cyanobacterium, Leptolyngbya sp. strain BL0902, is comparable to Arthrospira (Spirulina) platensis in commercial-scale cultivation while proving to be more genetically tractable. Here, we report the analyses of the whole genome sequence, gene inactivation/overexpression in the chromosome and deletion of non-essential chromosomal regions in this strain. The genetic manipulations were performed via homologous double recombination using either an antibiotic resistance marker or the CRISPR/Cpf1 editing system for positive selection. A desD-overexpressing strain produced γ-linolenic acid in an open raceway photobioreactor with the productivity of 0.36 g·m-2·d-1. Deletion mutants of predicted patX and hetR, two genes with opposite effects on cell differentiation in heterocyst-forming species, were used to demonstrate an analysis of the relationship between regulatory genes in the non-heterocystous species. Furthermore, a 50.8-kb chromosomal region was successfully deleted in BL0902 with the Cpf1 system. These results supported that BL0902 can be developed into a stable photosynthetic cell factory for synthesizing high value-added products, or used as a model strain for investigating the functions of genes that are unique to filamentous cyanobacteria, and could be systematically modified into a genome-streamlined chassis for synthetic biological purposes.
Collapse
Affiliation(s)
- Hong Gao
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Yali Wang
- School of Life Sciences, Central China Normal University, Wuhan, China
| | - Ziling Huang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Feiqi Yu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- School of Life Sciences, Central China Normal University, Wuhan, China
| | - Xi Hu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Degang Ning
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Xudong Xu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- School of Life Sciences, Central China Normal University, Wuhan, China
| |
Collapse
|
3
|
Glasgo LD, Lukasiak KL, Zinser ER. Expanding the capabilities of MuGENT for large-scale genetic engineering of the fastest-replicating species, Vibrio natriegens. Microbiol Spectr 2024; 12:e0396423. [PMID: 38667341 PMCID: PMC11237659 DOI: 10.1128/spectrum.03964-23] [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: 12/11/2023] [Accepted: 03/27/2024] [Indexed: 06/06/2024] Open
Abstract
The fastest replicating bacterium Vibrio natriegens is a rising workhorse for molecular and biotechnological research with established tools for efficient genetic manipulation. Here, we expand on the capabilities of multiplex genome editing by natural transformation (MuGENT) by identifying a neutral insertion site and showing how two selectable markers can be swapped at this site for sequential rounds of natural transformation. Second, we demonstrated that MuGENT can be used for complementation by gene insertion at an ectopic chromosomal locus. Additionally, we developed a robust method to cure the competence plasmid required to induce natural transformation. Finally, we demonstrated the ability of MuGENT to create massive deletions; the 280 kb deletion created in this study is one of the largest artificial deletions constructed in a single round of targeted mutagenesis of a bacterium. These methods each advance the genetic potential of V. natriegens and collectively expand upon its utility as an emerging model organism for synthetic biology. IMPORTANCE Vibrio natriegens is an emerging model organism for molecular and biotechnological applications. Its fast growth, metabolic versatility, and ease of genetic manipulation provide an ideal platform for synthetic biology. Here, we develop and apply novel methods that expand the genetic capabilities of the V. natriegens model system. Prior studies developed a method to manipulate multiple regions of the chromosome in a single step. Here, we provide new resources that diversify the utility of this method. We also provide a technique to remove the required genetic tools from the cell once the manipulation is performed, thus establishing "clean" derivative cells. Finally, we show the full extent of this technique's capability by generating one of the largest chromosomal deletions reported in the literature. Collectively, these new tools will be beneficial broadly to the Vibrio community and specifically to the advancement of V. natriegens as a model system.
Collapse
Affiliation(s)
- Liz D. Glasgo
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
| | - Katie L. Lukasiak
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
| | - Erik R. Zinser
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
| |
Collapse
|
4
|
Ma S, Su T, Lu X, Qi Q. Bacterial genome reduction for optimal chassis of synthetic biology: a review. Crit Rev Biotechnol 2024; 44:660-673. [PMID: 37380345 DOI: 10.1080/07388551.2023.2208285] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/13/2022] [Accepted: 02/20/2023] [Indexed: 06/30/2023]
Abstract
Bacteria with streamlined genomes, that harbor full functional genes for essential metabolic networks, are able to synthesize the desired products more effectively and thus have advantages as production platforms in industrial applications. To obtain streamlined chassis genomes, a large amount of effort has been made to reduce existing bacterial genomes. This work falls into two categories: rational and random reduction. The identification of essential gene sets and the emergence of various genome-deletion techniques have greatly promoted genome reduction in many bacteria over the past few decades. Some of the constructed genomes possessed desirable properties for industrial applications, such as: increased genome stability, transformation capacity, cell growth, and biomaterial productivity. The decreased growth and perturbations in physiological phenotype of some genome-reduced strains may limit their applications as optimized cell factories. This review presents an assessment of the advancements made to date in bacterial genome reduction to construct optimal chassis for synthetic biology, including: the identification of essential gene sets, the genome-deletion techniques, the properties and industrial applications of artificially streamlined genomes, the obstacles encountered in constructing reduced genomes, and the future perspectives.
Collapse
Affiliation(s)
- Shuai Ma
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, P. R. China
| | - Tianyuan Su
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, P. R. China
| | - Xuemei Lu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, P. R. China
| | - Qingsheng Qi
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, P. R. China
| |
Collapse
|
5
|
Jerabek T, Weiß L, Fahrion H, Zeh N, Raab N, Lindner B, Fischer S, Otte K. In pursuit of a minimal CHO genome: Establishment of large-scale genome deletions. N Biotechnol 2024; 79:100-110. [PMID: 38154614 DOI: 10.1016/j.nbt.2023.12.007] [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: 10/20/2023] [Revised: 11/27/2023] [Accepted: 12/24/2023] [Indexed: 12/30/2023]
Abstract
Chinese hamster ovary (CHO) cells are the most commonly used mammalian cell line for the production of complex therapeutic glycoproteins. As CHO cells have evolved as part of a multicellular organism, they harbor many cellular functions irrelevant for their application as production hosts in industrial bioprocesses. Consequently, CHO cells have been the target for numerous genetic engineering efforts in the past, but a tailored host cell chassis holistically optimized for its specific task in a bioreactor is still missing. While the concept of genome reduction has already been successfully applied to bacterial production cells, attempts to create higher eukaryotic production hosts exhibiting reduced genomes have not been reported yet. Here, we present the establishment and application of a large-scale genome deletion strategy for targeted excision of large genomic regions in CHO cells. We demonstrate the feasibility of genome reduction in CHO cells using optimized CRISPR/Cas9 based experimental protocols targeting large non-essential genomic regions with high efficiency. Achieved genome deletions of non-essential genetic regions did not introduce negative effects on bioprocess relevant parameters, although we conducted the largest reported genomic excision of 864 kilobase pairs in CHO cells so far. The concept presented serves as a directive to accelerate the development of a significantly genome-reduced CHO host cell chassis paving the way for a next generation of CHO cell factories.
Collapse
Affiliation(s)
- Tobias Jerabek
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany.
| | - Linus Weiß
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany
| | - Hannah Fahrion
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany
| | - Nikolas Zeh
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany; Boehringer Ingelheim Pharma GmbH & Co KG, Bioprocess Development Biologicals, Cell Line Development, Biberach, Germany
| | - Nadja Raab
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany
| | - Benjamin Lindner
- Boehringer Ingelheim Pharma GmbH & Co KG, Bioprocess Development Biologicals, Cell Line Development, Biberach, Germany
| | - Simon Fischer
- Boehringer Ingelheim Pharma GmbH & Co KG, Bioprocess Development Biologicals, Cell Line Development, Biberach, Germany
| | - Kerstin Otte
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany
| |
Collapse
|
6
|
Amendola CR, Cordell WT, Kneucker CM, Szostkiewicz CJ, Ingraham MA, Monninger M, Wilton R, Pfleger BF, Salvachúa D, Johnson CW, Beckham GT. Comparison of wild-type KT2440 and genome-reduced EM42 Pseudomonas putida strains for muconate production from aromatic compounds and glucose. Metab Eng 2024; 81:88-99. [PMID: 38000549 DOI: 10.1016/j.ymben.2023.11.004] [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: 08/02/2023] [Revised: 11/12/2023] [Accepted: 11/19/2023] [Indexed: 11/26/2023]
Abstract
Pseudomonas putida KT2440 is a robust, aromatic catabolic bacterium that has been widely engineered to convert bio-based and waste-based feedstocks to target products. Towards industrial domestication of P. putida KT2440, rational genome reduction has been previously conducted, resulting in P. putida strain EM42, which exhibited characteristics that could be advantageous for production strains. Here, we compared P. putida KT2440- and EM42-derived strains for cis,cis-muconic acid production from an aromatic compound, p-coumarate, and in separate strains, from glucose. To our surprise, the EM42-derived strains did not outperform the KT2440-derived strains in muconate production from either substrate. In bioreactor cultivations, KT2440- and EM42-derived strains produced muconate from p-coumarate at titers of 45 g/L and 37 g/L, respectively, and from glucose at 20 g/L and 13 g/L, respectively. To provide additional insights about the differences in the parent strains, we analyzed growth profiles of KT2440 and EM42 on aromatic compounds as the sole carbon and energy sources. In general, the EM42 strain exhibited reduced growth rates but shorter growth lags than KT2440. We also observed that EM42-derived strains resulted in higher growth rates on glucose compared to KT2440-derived strains, but only at the lowest glucose concentrations tested. Transcriptomics revealed that genome reduction in EM42 had global effects on transcript levels and showed that the EM42-derived strains that produce muconate from glucose exhibit reduced modulation of gene expression in response to changes in glucose concentrations. Overall, our results highlight that additional studies are warranted to understand the effects of genome reduction on microbial metabolism and physiology, especially when intended for use in production strains.
Collapse
Affiliation(s)
- Caroline R Amendola
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Agile BioFoundry, Emeryville, CA, 94608, USA
| | - William T Cordell
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Colin M Kneucker
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Agile BioFoundry, Emeryville, CA, 94608, USA
| | - Caralyn J Szostkiewicz
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Agile BioFoundry, Emeryville, CA, 94608, USA
| | - Morgan A Ingraham
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Agile BioFoundry, Emeryville, CA, 94608, USA
| | - Michela Monninger
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Agile BioFoundry, Emeryville, CA, 94608, USA
| | - Rosemarie Wilton
- Agile BioFoundry, Emeryville, CA, 94608, USA; Biosciences Division Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Brian F Pfleger
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Davinia Salvachúa
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Agile BioFoundry, Emeryville, CA, 94608, USA
| | - Christopher W Johnson
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Agile BioFoundry, Emeryville, CA, 94608, USA.
| | - Gregg T Beckham
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Agile BioFoundry, Emeryville, CA, 94608, USA.
| |
Collapse
|
7
|
Enright AL, Banta AB, Ward RD, Rivera Vazquez J, Felczak MM, Wolfe MB, TerAvest MA, Amador-Noguez D, Peters JM. The genetics of aerotolerant growth in an alphaproteobacterium with a naturally reduced genome. mBio 2023; 14:e0148723. [PMID: 37905909 PMCID: PMC10746277 DOI: 10.1128/mbio.01487-23] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 09/25/2023] [Indexed: 11/02/2023] Open
Abstract
IMPORTANCE The inherent complexity of biological systems is a major barrier to our understanding of cellular physiology. Bacteria with markedly fewer genes than their close relatives, or reduced genome bacteria, are promising biological models with less complexity. Reduced genome bacteria can also have superior properties for industrial use, provided the reduction does not overly restrict strain robustness. Naturally reduced genome bacteria, such as the alphaproteobacterium Zymomonas mobilis, have fewer genes but remain environmentally robust. In this study, we show that Z. mobilis is a simplified genetic model for Alphaproteobacteria, a class with important impacts on the environment, human health, and industry. We also identify genes that are only required in the absence of atmospheric oxygen, uncovering players that maintain and utilize the cellular energy state. Our findings have broad implications for the genetics of Alphaproteobacteria and industrial use of Z. mobilis to create biofuels and bioproducts.
Collapse
Affiliation(s)
- Amy L. Enright
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Amy B. Banta
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Ryan D. Ward
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Julio Rivera Vazquez
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Magdalena M. Felczak
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Michael B. Wolfe
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Michaela A. TerAvest
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Daniel Amador-Noguez
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Jason M. Peters
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, Wisconsin, USA
| |
Collapse
|
8
|
Matteau D, Champie A, Grenier F, Rodrigue S. Complete sequence of the genome-reduced Escherichia coli DGF-298. Microbiol Resour Announc 2023; 12:e0066523. [PMID: 37843363 PMCID: PMC10652928 DOI: 10.1128/mra.00665-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 08/31/2023] [Indexed: 10/17/2023] Open
Abstract
We report the complete genome sequence and annotation of Escherichia coli DGF-298, a genome-reduced E. coli strain with interesting properties for systems and synthetic biology. DGF-298 has a single circular chromosome of 2,991,126 bp and 2,831 genes, including 2,691 coding sequences, with a mean G + C content of ~51%.
Collapse
Affiliation(s)
- Dominick Matteau
- Département de Biologie, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Antoine Champie
- Département de Biologie, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Frédéric Grenier
- Département de Biologie, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Sébastien Rodrigue
- Département de Biologie, Université de Sherbrooke, Sherbrooke, Québec, Canada
| |
Collapse
|
9
|
Aida H, Ying BW. Efforts to Minimise the Bacterial Genome as a Free-Living Growing System. BIOLOGY 2023; 12:1170. [PMID: 37759570 PMCID: PMC10525146 DOI: 10.3390/biology12091170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 08/17/2023] [Accepted: 08/24/2023] [Indexed: 09/29/2023]
Abstract
Exploring the minimal genetic requirements for cells to maintain free living is an exciting topic in biology. Multiple approaches are employed to address the question of the minimal genome. In addition to constructing the synthetic genome in the test tube, reducing the size of the wild-type genome is a practical approach for obtaining the essential genomic sequence for living cells. The well-studied Escherichia coli has been used as a model organism for genome reduction owing to its fast growth and easy manipulation. Extensive studies have reported how to reduce the bacterial genome and the collections of genomic disturbed strains acquired, which were sufficiently reviewed previously. However, the common issue of growth decrease caused by genetic disturbance remains largely unaddressed. This mini-review discusses the considerable efforts made to improve growth fitness, which was decreased due to genome reduction. The proposal and perspective are clarified for further accumulated genetic deletion to minimise the Escherichia coli genome in terms of genome reduction, experimental evolution, medium optimization, and machine learning.
Collapse
Affiliation(s)
| | - Bei-Wen Ying
- School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
| |
Collapse
|
10
|
Kotaka Y, Hashimoto M, Lee KI, Kato JI. Mutations identified in engineered Escherichia coli with a reduced genome. Front Microbiol 2023; 14:1189877. [PMID: 37303809 PMCID: PMC10249474 DOI: 10.3389/fmicb.2023.1189877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 05/08/2023] [Indexed: 06/13/2023] Open
Abstract
Characterizing genes that regulate cell growth and survival in model organisms is important for understanding higher organisms. Construction of strains harboring large deletions in the genome can provide insights into the genetic basis of cell growth compared with only studying wild-type strains. We have constructed a series of genome-reduced strains with deletions spanning approximately 38.9% of the E. coli chromosome. Strains were constructed by combining large deletions in chromosomal regions encoding nonessential gene groups. We also isolated strains Δ33b and Δ37c, whose growth was partially restored by adaptive laboratory evolution (ALE). Genome sequencing of nine strains, including those selected following ALE, identified the presence of several Single Nucleotide Variants (SNVs), insertions, deletions, and inversions. In addition to multiple SNVs, two insertions were identified in ALE strain Δ33b. The first was an insertion at the promoter region of pntA, which increased cognate gene expression. The second was an insertion sequence (IS) present in sibE, encoding the antitoxin in a toxin-antitoxin system, which decreased expression of sibE. 5 strains of Δ37c independently isolated following ALE harboring multiple SNVs and genetic rearrangements. Interestingly, a SNV was identified in the promoter region of hcaT in all five strains, which increased hcaT expression and, we predict, rescued the attenuated Δ37b growth. Experiments using defined deletion mutants suggested that hcaT encodes a 3-phenylpropionate transporter protein and is involved in survival during stationary phase under oxidative stress. This study is the first to document accumulation of mutations during construction of genome-reduced strains. Furthermore, isolation and analysis of strains derived from ALE in which the growth defect mediated by large chromosomal deletions was rescued identified novel genes involved in cell survival.
Collapse
Affiliation(s)
- Yuto Kotaka
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Tokyo, Japan
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Masayuki Hashimoto
- Institute of Molecular Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Ken-ichi Lee
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Jun-ichi Kato
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Tokyo, Japan
| |
Collapse
|
11
|
Hou F, Ke Z, Xu Y, Wang Y, Zhu G, Gao H, Ji S, Xu X. Systematic Large Fragment Deletions in the Genome of Synechococcus elongatus and the Consequent Changes in Transcriptomic Profiles. Genes (Basel) 2023; 14:genes14051091. [PMID: 37239451 DOI: 10.3390/genes14051091] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/12/2023] [Accepted: 05/12/2023] [Indexed: 05/28/2023] Open
Abstract
Genome streamlining, as a natural process in the evolution of microbes, has become a common approach for generating ideal chassis cells for synthetic biology studies and industrial applications. However, systematic genome reduction remains a bottleneck in the generation of such chassis cells with cyanobacteria, due to very time-consuming genetic manipulations. Synechococcus elongatus PCC 7942, a unicellular cyanobacterium, is a candidate for systematic genome reduction, as its essential and nonessential genes have been experimentally identified. Here, we report that at least 20 of the 23 over 10 kb nonessential gene regions could be deleted and that stepwise deletions of these regions could be achieved. A septuple-deletion mutant (genome reduced by 3.8%) was generated, and the effects of genome reduction on the growth and genome-wide transcription were investigated. In the ancestral triple to sextuple mutants (b, c, d, e1), an increasingly large number of genes (up to 998) were upregulated relative to the wild type, while slightly fewer genes (831) were upregulated in the septuple mutant (f). In a different sextuple mutant (e2) derived from the quintuple mutant d, much fewer genes (232) were upregulated. Under the standard conditions in this study, the mutant e2 showed a higher growth rate than the wild type, e1 and f. Our results indicate that it is feasible to extensively reduce the genomes of cyanobacteria for generation of chassis cells and for experimental evolutionary studies.
Collapse
Affiliation(s)
- Feifei Hou
- College of Fisheries and Life Science, Dalian Ocean University, Dalian 116000, China
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Zhufang Ke
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yi Xu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yali Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, China
| | - Geqian Zhu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Hong Gao
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Shuiling Ji
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, China
| | - Xudong Xu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| |
Collapse
|
12
|
Matsui Y, Nagai M, Ying BW. Growth rate-associated transcriptome reorganization in response to genomic, environmental, and evolutionary interruptions. Front Microbiol 2023; 14:1145673. [PMID: 37032868 PMCID: PMC10073601 DOI: 10.3389/fmicb.2023.1145673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 03/02/2023] [Indexed: 04/11/2023] Open
Abstract
The genomic, environmental, and evolutionary interruptions caused the changes in bacterial growth, which were stringently associated with changes in gene expression. The growth and gene expression changes remained unclear in response to these interruptions that occurred combinative. As a pilot study, whether and how bacterial growth was affected by the individual and dual interruptions of genome reduction, environmental stress, and adaptive evolution were investigated. Growth assay showed that the presence of the environmental stressors, i.e., threonine and chloramphenicol, significantly decreased the growth rate of the wild-type Escherichia coli, whereas not that of the reduced genome. It indicated a canceling effect in bacterial growth due to the dual interruption of the genomic and environmental changes. Experimental evolution of the reduced genome released the canceling effect by improving growth fitness. Intriguingly, the transcriptome architecture maintained a homeostatic chromosomal periodicity regardless of the genomic, environmental, and evolutionary interruptions. Negative epistasis in transcriptome reorganization was commonly observed in response to the dual interruptions, which might contribute to the canceling effect. It was supported by the changes in the numbers of differentially expressed genes (DEGs) and the enriched regulons and functions. Gene network analysis newly constructed 11 gene modules, one out of which was correlated to the growth rate. Enrichment of DEGs in these modules successfully categorized them into three types, i.e., conserved, responsive, and epistatic. Taken together, homeostasis in transcriptome architecture was essential to being alive, and it might be attributed to the negative epistasis in transcriptome reorganization and the functional differentiation in gene modules. The present study directly connected bacterial growth fitness with transcriptome reorganization and provided a global view of how microorganisms responded to genomic, environmental, and evolutionary interruptions for survival from wild nature.
Collapse
|
13
|
Gomide MDS, Leitão MDC, Coelho CM. Biocircuits in plants and eukaryotic algae. FRONTIERS IN PLANT SCIENCE 2022; 13:982959. [PMID: 36212277 PMCID: PMC9545776 DOI: 10.3389/fpls.2022.982959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/22/2022] [Indexed: 06/16/2023]
Abstract
As one of synthetic biology's foundations, biocircuits are a strategy of genetic parts assembling to recognize a signal and to produce a desirable output to interfere with a biological function. In this review, we revisited the progress in the biocircuits technology basis and its mandatory elements, such as the characterization and assembly of functional parts. Furthermore, for a successful implementation, the transcriptional control systems are a relevant point, and the computational tools help to predict the best combinations among the biological parts planned to be used to achieve the desirable phenotype. However, many challenges are involved in delivering and stabilizing the synthetic structures. Some research experiences, such as the golden crops, biosensors, and artificial photosynthetic structures, can indicate the positive and limiting aspects of the practice. Finally, we envision that the modulatory structural feature and the possibility of finer gene regulation through biocircuits can contribute to the complex design of synthetic chromosomes aiming to develop plants and algae with new or improved functions.
Collapse
Affiliation(s)
- Mayna da Silveira Gomide
- Laboratory of Synthetic Biology, Department of Genetics and Morphology, Institute of Biological Science, University of Brasília (UnB), Brasília, Distrito Federal, Brazil
- School of Medicine, Federal University of Juiz de Fora (UFJF), Juiz de Fora, Minas Gerais, Brazil
| | - Matheus de Castro Leitão
- Laboratory of Synthetic Biology, Department of Genetics and Morphology, Institute of Biological Science, University of Brasília (UnB), Brasília, Distrito Federal, Brazil
| | - Cíntia Marques Coelho
- Laboratory of Synthetic Biology, Department of Genetics and Morphology, Institute of Biological Science, University of Brasília (UnB), Brasília, Distrito Federal, Brazil
| |
Collapse
|
14
|
Lao Z, Matsui Y, Ijichi S, Ying BW. Global coordination of the mutation and growth rates across the genetic and nutritional variety in Escherichia coli. Front Microbiol 2022; 13:990969. [PMID: 36204613 PMCID: PMC9530902 DOI: 10.3389/fmicb.2022.990969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 08/30/2022] [Indexed: 11/24/2022] Open
Abstract
Fitness and mutability are the primary traits of living organisms for adaptation and evolution. However, their quantitative linkage remained largely deficient. Whether there is any general relationship between the two features and how genetic and environmental variables influence them remained unclear and were addressed here. The mutation and growth rates of an assortment of Escherichia coli strain collections, including the wild-type strains and the genetically disturbed strains of either reduced genomes or deletion of the genes involved in the DNA replication fidelity, were evaluated in various media. The contribution of media to the mutation and growth rates was differentiated depending on the types of genetic disturbance. Nevertheless, the negative correlation between the mutation and growth rates was observed across the genotypes and was common in all media. It indicated the comprehensive association of the correlated mutation and growth rates with the genetic and medium variation. Multiple linear regression and support vector machine successfully predicted the mutation and growth rates and the categories of genotypes and media, respectively. Taken together, the study provided a quantitative dataset linking the mutation and growth rates, genotype, and medium and presented a simple and successful example of predicting bacterial growth and mutability by data-driven approaches.
Collapse
|
15
|
Ma S, Su T, Liu J, Wang Q, Liang Q, Lu X, Qi Q. Random genome reduction coupled with polyhydroxybutyrate biosynthesis to facilitate its accumulation in Escherichia coli. Front Bioeng Biotechnol 2022; 10:978211. [PMID: 36105609 PMCID: PMC9465206 DOI: 10.3389/fbioe.2022.978211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
Genome reduction has been emerged as a powerful tool to construct ideal chassis for synthetic biology. Random genome reduction couple genomic deletion with growth and has the potential to construct optimum genome for a given environment. Recently, we developed a transposon-mediated random deletion (TMRD) method that allows the random and continuous reduction of Escherichia coli genome. Here, to prove its ability in constructing optimal cell factories, we coupled polyhydroxybutyrate (PHB) accumulation with random genome reduction and proceeded to reduce the E. coli genome. Five mutants showed high biomass and PHB yields were selected from 18 candidates after ten rounds of genome reduction. And eight or nine genomic fragments (totally 230.1–270.0 Kb) were deleted in their genomes, encompassing 4.95%–5.82% of the parental MG1655 genome. Most mutants displayed better growth, glucose utilization, protein expression, and significant increase of electroporation efficiency compared with MG1655. The PHB content and concentration enhanced up to 13.3%–37.2% and 60.2%–102.9% when batch fermentation was performed in M9-glucose medium using the five mutants. Particularly, in mutant H16, lacking 5.28% of its genome, the increase of biomass and PHB concentration were more than 50% and 100% compared with MG1655, respectively. This work expands the strategy for creating streamlined chassis to improve the production of high value-added products.
Collapse
Affiliation(s)
| | | | | | | | | | - Xuemei Lu
- *Correspondence: Xuemei Lu, ; Qingsheng Qi,
| | | |
Collapse
|
16
|
Kondratyeva L, Alekseenko I, Chernov I, Sverdlov E. Data Incompleteness May form a Hard-to-Overcome Barrier to Decoding Life's Mechanism. BIOLOGY 2022; 11:1208. [PMID: 36009835 PMCID: PMC9404739 DOI: 10.3390/biology11081208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 08/03/2022] [Accepted: 08/10/2022] [Indexed: 11/23/2022]
Abstract
In this brief review, we attempt to demonstrate that the incompleteness of data, as well as the intrinsic heterogeneity of biological systems, may form very strong and possibly insurmountable barriers for researchers trying to decipher the mechanisms of the functioning of live systems. We illustrate this challenge using the two most studied organisms: E. coli, with 34.6% genes lacking experimental evidence of function, and C. elegans, with identified proteins for approximately 50% of its genes. Another striking example is an artificial unicellular entity named JCVI-syn3.0, with a minimal set of genes. A total of 31.5% of the genes of JCVI-syn3.0 cannot be ascribed a specific biological function. The human interactome mapping project identified only 5-10% of all protein interactions in humans. In addition, most of the available data are static snapshots, and it is barely possible to generate realistic models of the dynamic processes within cells. Moreover, the existing interactomes reflect the de facto interaction but not its functional result, which is an unpredictable emerging property. Perhaps the completeness of molecular data on any living organism is beyond our reach and represents an unsolvable problem in biology.
Collapse
Affiliation(s)
- Liya Kondratyeva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow 117997, Russia
| | - Irina Alekseenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow 117997, Russia
- Institute of Molecular Genetics of National Research Centre “Kurchatov Institute”, Moscow 123182, Russia
| | - Igor Chernov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow 117997, Russia
| | - Eugene Sverdlov
- Institute of Molecular Genetics of National Research Centre “Kurchatov Institute”, Moscow 123182, Russia
- Kurchatov Center for Genome Research, National Research Center “Kurchatov Institute”, Moscow 123182, Russia
| |
Collapse
|
17
|
Ma S, Su T, Liu J, Lu X, Qi Q. Reduction of the Bacterial Genome by Transposon-Mediated Random Deletion. ACS Synth Biol 2022; 11:668-677. [PMID: 35104106 DOI: 10.1021/acssynbio.1c00353] [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] [Indexed: 11/28/2022]
Abstract
Genome reduction is an important strategy in synthetic biology for constructing functional chassis cells or minimal genomes. However, the limited knowledge of complex gene functions and interactions makes genome reduction by rational design encounter a bottleneck. Here, we present an iterative and random genome reduction method for Escherichia coli, named "transposon-mediated random deletion (TMRD)". TMRD generates random double-strand breaks (DSBs) in the genome by combining Tn5 transposition with the CRISPR/Cas9 system and allows genomic deletions of various sizes at random positions during DSB repair through the intracellular alternative end-joining mechanism. Using E. coli MG1655 as the original strain, a pool of cells with multiple random genomic deletions were obtained after five reduction cycles. The growth rates of the obtained cells were comparable to that of MG1655, while the electroporation efficiency increased by at least 2 magnitudes. TMRD can generate a small E. coli library carrying multiple and random genomic deletions while enriching the cells with environmental fitness in the population. TMRD has the potential to be widely applied in the construction of minimal genomes or chassis cells for metabolic engineering.
Collapse
Affiliation(s)
- Shuai Ma
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, P. R. China
| | - Tianyuan Su
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, P. R. China
| | - Jinming Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, P. R. China
| | - Xuemei Lu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, P. R. China
| | - Qingsheng Qi
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, P. R. China
| |
Collapse
|
18
|
Wang ZK, Gong JS, Qin J, Li H, Lu ZM, Shi JS, Xu ZH. Improving the Intensity of Integrated Expression for Microbial Production. ACS Synth Biol 2021; 10:2796-2807. [PMID: 34738786 DOI: 10.1021/acssynbio.1c00334] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Chromosomal integration of exogenous genes is preferred for industrially related fermentation, as plasmid-mediated fermentation leads to extra metabolic burden and genetic instability. Moreover, with the development and advancement of genome engineering and gene editing technologies, inserting genes into chromosomes has become more convenient; integration expression is extensively utilized in microorganisms for industrial bioproduction and expected to become the trend of recombinant protein expression. However, in actual research and application, it is important to enhance the expression of heterologous genes at the host genome level. Herein, we summarized the basic principles and characteristics of genomic integration; furthermore, we highlighted strategies to improve the expression of chromosomal integration of genes and pathways in host strains from three aspects, including chassis cell optimization, regulation of expression elements in gene expression cassettes, optimization of gene dose level and integration sites on chromosomes. Moreover, we reviewed and summarized the relevant studies on the application of integrated expression in the exploration of gene function and the various types of industrial microorganism production. Consequently, this review would serve as a reference for the better application of integrated expression.
Collapse
Affiliation(s)
- Zi-Kai Wang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Jiufu Qin
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, PR China
| | - Hui Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Zhen-Ming Lu
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Zheng-Hong Xu
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, PR China
| |
Collapse
|
19
|
Correlated chromosomal periodicities according to the growth rate and gene expression. Sci Rep 2020; 10:15531. [PMID: 32968121 PMCID: PMC7511328 DOI: 10.1038/s41598-020-72389-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 08/10/2020] [Indexed: 12/02/2022] Open
Abstract
Linking genetic information to population fitness is crucial to understanding living organisms. Despite the abundant knowledge of the genetic contribution to growth, the overall patterns/features connecting genes, their expression, and growth remain unclear. To reveal the quantitative and direct connections, systematic growth assays of single-gene knockout Escherichia coli strains under both rich and poor nutritional conditions were performed; subsequently, the resultant growth rates were associated with the original expression levels of the knockout genes in the parental genome. Comparative analysis of growth and the transcriptome identified not only the nutritionally differentiated fitness cost genes but also a significant correlation between the growth rates of the single-gene knockout strains and the original expression levels of these knockout genes in the parental strain, regardless of the nutritional variation. In addition, the coordinated chromosomal periodicities of the wild-type transcriptome and the growth rates of the strains lacking the corresponding genes were observed. The common six-period periodicity was somehow attributed to the essential genes, although the underlying mechanism remains to be addressed. The correlated chromosomal periodicities associated with the gene expression-growth dataset were highly valuable for bacterial growth prediction and discovering the working principles governing minimal genetic information.
Collapse
|
20
|
de la Cruz M, Ramírez EA, Sigala JC, Utrilla J, Lara AR. Plasmid DNA Production in Proteome-Reduced Escherichia coli. Microorganisms 2020; 8:microorganisms8091444. [PMID: 32967123 PMCID: PMC7563601 DOI: 10.3390/microorganisms8091444] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/05/2020] [Accepted: 09/11/2020] [Indexed: 11/16/2022] Open
Abstract
The design of optimal cell factories requires engineering resource allocation for maximizing product synthesis. A recently developed method to maximize the saving in cell resources released 0.5% of the proteome of Escherichia coli by deleting only three transcription factors. We assessed the capacity for plasmid DNA (pDNA) production in the proteome-reduced strain in a mineral medium, lysogeny, and terrific broths. In all three cases, the pDNA yield from biomass was between 33 and 53% higher in the proteome-reduced than in its wild type strain. When cultured in fed-batch mode in shake-flask, the proteome-reduced strain produced 74.8 mg L-1 pDNA, which was four times greater than its wild-type strain. Nevertheless, the pDNA supercoiled fraction was less than 60% in all cases. Deletion of recA increased the pDNA yields in the wild type, but not in the proteome-reduced strain. Furthermore, recA mutants produced a higher fraction of supercoiled pDNA, compared to their parents. These results show that the novel proteome reduction approach is a promising starting point for the design of improved pDNA production hosts.
Collapse
Affiliation(s)
- Mitzi de la Cruz
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Cuajimalpa, Mexico City 05348, Mexico; (M.d.l.C.); (E.A.R.); (J.-C.S.)
| | - Elisa A. Ramírez
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Cuajimalpa, Mexico City 05348, Mexico; (M.d.l.C.); (E.A.R.); (J.-C.S.)
| | - Juan-Carlos Sigala
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Cuajimalpa, Mexico City 05348, Mexico; (M.d.l.C.); (E.A.R.); (J.-C.S.)
| | - José Utrilla
- Systems and Synthetic Biology Program, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca 62210, Mexico;
| | - Alvaro R. Lara
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Cuajimalpa, Mexico City 05348, Mexico; (M.d.l.C.); (E.A.R.); (J.-C.S.)
- Correspondence:
| |
Collapse
|
21
|
Cao YY, Yomo T, Ying BW. Clustering of Bacterial Growth Dynamics in Response to Growth Media by Dynamic Time Warping. Microorganisms 2020; 8:microorganisms8030331. [PMID: 32111085 PMCID: PMC7143780 DOI: 10.3390/microorganisms8030331] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 02/18/2020] [Accepted: 02/25/2020] [Indexed: 01/17/2023] Open
Abstract
Bacterial growth curves, representing population dynamics, are still poorly understood. The growth curves are commonly analyzed by model-based theoretical fitting, which is limited to typical S-shape fittings and does not elucidate the dynamics in their entirety. Thus, whether a certain growth condition results in any particular pattern of growth curve remains unclear. To address this question, up-to-date data mining techniques were applied to bacterial growth analysis for the first time. Dynamic time warping (DTW) and derivative DTW (DDTW) were used to compare the similarity among 1015 growth curves of 28 Escherichia coli strains growing in three different media. In the similarity evaluation, agglomerative hierarchical clustering, assessed with four statistic benchmarks, successfully categorized the growth curves into three clusters, roughly corresponding to the three media. Furthermore, a simple benchmark was newly proposed, providing a highly improved accuracy (~99%) in clustering the growth curves corresponding to the growth media. The biologically reasonable categorization of growth curves suggested that DTW and DDTW are applicable for bacterial growth analysis. The bottom-up clustering results indicate that the growth media determine some specific patterns of population dynamics, regardless of genomic variation, and thus have a higher priority of shaping the growth curves than the genomes do.
Collapse
Affiliation(s)
- Yang-Yang Cao
- Software Engineering Institute, East China Normal University, 3663 Zhong Shan Road (N), Shanghai 200062, China;
| | - Tetsuya Yomo
- School of Life Science, East China Normal University, 3663 Zhong Shan Road (N), Shanghai 200062, China
- Correspondence: (T.Y.); (B.-W.Y.); Tel.: +81-(0)29-853-6633 (B.-W.Y.)
| | - Bei-Wen Ying
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8572, Japan
- Correspondence: (T.Y.); (B.-W.Y.); Tel.: +81-(0)29-853-6633 (B.-W.Y.)
| |
Collapse
|