Methylotroph Communities Methylotrophs

Total Page:16

File Type:pdf, Size:1020Kb

Methylotroph Communities Methylotrophs Chapter 14 from: Methylotrophs and Methylotroph Communities Edited by Ludmila Chistoserdova ISBN: 978-1-912530-04-5 (hardback) ISBN: 978-1-912530-05-2 (ebook) Published by Caister Academic Press https://www.caister.com Synthetic Methanol and Formate Assimilation Via Modular Engineering 14 and Selection Strategies Nico J. Claassens, Hai He and Arren Bar-Even* Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany. *Correspondence: [email protected] htps://doi.org/10.21775/9781912530045.14 Abstract Introduction One-carbon (C1) feedstocks can provide a One-carbon (C1) compounds could prove to be vital link between cheap and sustainable abiotic a crucial link between the abiotic and the biotic resources and microbial bioproduction. Soluble C1 worlds. Tese feedstocks can be obtained from substrates – methanol and formate – could prove low-cost and abundant sources, such as syngas and to be more suitable than gaseous feedstocks as they natural gas (Dürre and Eikmanns, 2015; Clomburg avoid mass transfer barriers. However, microorgan- et al., 2017), and can be produced directly from isms that naturally assimilate methanol and formate CO2 using energy sources such as sunlight and are limited by a narrow product spectrum and a renewable electricity (Kumar et al., 2012; Martín et restricted genetic toolbox. Engineering biotech- al., 2015; Claassens et al., 2018; Jouny et al., 2018). nological organisms to assimilate these soluble C1 Multiple microorganisms can be cultivated on C1 substrates has therefore become an atractive goal. compounds as sole carbon and energy sources, thus Here, we discuss the use of a step-wise, modular opening new avenues for sustainable bioproduc- engineering approach for the implementation of tion. C1 assimilation pathways. In this strategy, pathways However, the use of microorganisms that can are divided into metabolic modules, the activities naturally grow on C1 substrates is limited by mul- of which are selected for in dedicated gene-deletion tiple factors, including a narrow product spectrum, strains whose growth directly depends on module low yields, titres, and productivities, a restricted activity. Tis provides an easy way to identify and genetic toolbox for engineering, and gaps in our resolve metabolic barriers hampering pathway per- understanding of their cellular physiology and formance. Optimization of gene expression levels metabolism (Whitaker et al., 2015; Clomburg et al., and adaptive laboratory evolution can be used to 2017). To overcome these difculties, recent meta- establish the desired activity if direct selection fails. bolic engineering eforts are aiming to introduce We exemplify this approach using several pathways, C1 assimilation pathways into model biotechno- focusing especially on the ribulose monophosphate logical microorganisms that are easier to engineer cycle for methanol assimilation and the reduc- and that can be beter optimized for industrially tive glycine pathway for formate assimilation. We relevant conditions. Tese eforts use either natural argue that such modular engineering and selection pathways that are known to sustain high yields, or, strategies will prove essential for rewiring microbial more boldly, synthetic pathways with low ATP cost metabolism towards new growth phenotypes and that could theoretically support increased yields sustainable bioproduction. (Bar-Even et al., 2013; Siegel et al., 2015; Bar-Even, 238 | Claassens et al. 2016;). Some of these synthetic pathways can Modularity and selection be established by combining naturally existing as metabolic engineering enzymes, while others include novel enzyme activi- strategies ties that can be realized by protein engineering Engineering synthetic C1 metabolism requires (Erb et al., 2017). In fact, engineered enzymes have the overexpression of pathway enzymes, especially already been demonstrated in vitro to support for- those that are missing in the host or that are natively mate assimilation (Siegel et al., 2015) and carbon expressed at insufcient levels. However, simple fxation (Schwander et al., 2016). overexpression is unlikely to be sufcient for realiz- In this review, we discuss metabolic engineer- ing the activity of the entire pathway. Tis is mainly ing studies aiming to introduce pathways for the because of the overlap between the introduced assimilation of the soluble C1 compounds metha- pathway and the host central metabolism, result- nol and formate, the utilization of which bypasses ing in disrupted fuxes through both systems. To the challenges associated with mass transfer of beter identify and resolve problematic metabolic gaseous C1 substrates, such as methane and carbon interactions, it is helpful to divide the synthetic monoxide (Henstra et al., 2007; Fei et al., 2014). pathway into smaller metabolic modules, i.e. sub- We specifcally focus on modular and selection- pathways consisting of several reactions (Fig. 14.1). based engineering strategies in which the activity Te in vivo implementation of these modules can of pathway segments is coupled to cellular growth. be considerably easier than the full pathway and We show that this step-wise approach is vital for the provide vital information on the metabolic context realization of synthetic C1 assimilation. that enables or constrains the newly introduced 1 2 3 4 Divide synthetic pathway Multiple expression levels for into several metabolic each enzyme are tested, modules, each corresponds for example by varying to a discrete metabolic goal strength of promoters, RBS, and plasmid origins of replication Express each module in a low high dedicated auxotrophic selection selection strain, the growth of which Increase selection for module strictly depends upon Fraction of cells activity in different strains, the module activity, enabling growth of each requires a direct selection for activity Protein level (log scale) different level of module activity If direct selection fails, or Feeding with 13C-labeled formate results in sub-optimal growth, (or another carbon source) and + long-term cultivation under monitoring the labeling pattern in selective conditions proteinogenic amino acids, we (chemostat or turbidostat) can confirm module activity or = evolves desired growth identify competing routes that properties should be deleted Sequence evolved strains, Integrate modules into a full O O feed introduce mutations to a H pathway within a strain carrying naïve strain to identify the 2 the beneficial mutations previously HC C H C contribution of each mutation, OH HO C OH identified, and select for growth via identify minimal set of the pathway, upon expression of the effluent mutations to enable activity NH2 (potentially evolved) pathway enzymes 5 6 7 8 Figure 14.1 A schematic representation of the modular engineering and selection approach outlined in this paper. Strategies for Synthetic C1 Assimilation | 239 activities. To probe the implementation of meta- and potentially also of related host enzymes, e.g. bolic modules, it is useful to couple their activity deletion or down-regulation of enzymes that with the growth of the host. divert metabolic intermediates from the pathway. Coupling module activity with growth usu- In addition, diferent enzyme variants or codon ally requires modifying the metabolic network of optimization of the relevant genes can sup- the host by performing strategic gene deletions. port increased expression and activity. Another Tese are made to generate a strain auxotrophic method, which does not rely on genetic tools, is for certain essential metabolic intermediates – for the addition of small molecules that specifcally example, an amino acid – which can be exclusively inhibit interfering enzymes, as demonstrated synthesized via the synthetic module. As a result, for the glycolytic glyceraldehyde 3-phosphate cellular growth becomes dependent on the activ- dehydrogenase in the engineering of methanol ity of the module. A range of selection strains can assimilation in Escherichia coli (Woolston et al., be designed with increasing selection pressure for 2018a). pathway activity: a ‘minimal’ selection is sustained If these approaches fail to establish module if the module provides a single required metabo- activity, adaptive laboratory evolution (ALE) can lite, higher selection pressure is obtained when be performed to increase module functionality module activity is responsible for the biosynthesis and establish module-dependent growth (Portnoy of multiple building blocks, and very high selection et al., 2011). For this process, the overexpressed pressure is imposed when the biosynthesis of all or genes should preferably be integrated into the most biomass is dependent on the module. genome rather than carried on a plasmid as to Te design of modules and selection strains increase the chance of benefcial mutations to be can be assisted by computational tools based on fxed in the population. Diferent types of ALE Flux Balance Analysis, for example OptKnock can be applied; a prominent approach being con- or FlexFlux (Burgard et al., 2003; Marmiesse et tinuous cultivation on a selective medium, with al., 2015; Meyer et al., 2018). Yet, in most cases, limiting amounts of the compounds for which the manual design based on biochemical and metabolic cells are auxotrophic. Tis method was applied knowledge sufces. Specifcally, when dividing a for the successful engineering of the CO2-fxing pathway into metabolic modules, several factors Calvin cycle in E. coli (Antonovsky et al., 2016), should be taken
Recommended publications
  • Identification of Active Methylotroph Populations in an Acidic Forest Soil
    Microbiology (2002), 148, 2331–2342 Printed in Great Britain Identification of active methylotroph populations in an acidic forest soil by stable- isotope probing Stefan Radajewski,1 Gordon Webster,2† David S. Reay,3‡ Samantha A. Morris,1 Philip Ineson,4 David B. Nedwell,3 James I. Prosser2 and J. Colin Murrell1 Author for correspondence: J. Colin Murrell. Tel: j44 24 7652 2553. Fax: j44 24 7652 3568. e-mail: cmurrell!bio.warwick.ac.uk 1 Department of Biological Stable-isotope probing (SIP) is a culture-independent technique that enables Sciences, University of the isolation of DNA from micro-organisms that are actively involved in a Warwick, Coventry CV4 7AL, UK specific metabolic process. In this study, SIP was used to characterize the active methylotroph populations in forest soil (pH 35) microcosms that were exposed 2 Department of Molecular 13 13 13 13 and Cell Biology, to CH3OH or CH4. Distinct C-labelled DNA ( C-DNA) fractions were resolved University of Aberdeen, from total community DNA by CsCl density-gradient centrifugation. Analysis of Institute of Medical 16S rDNA sequences amplified from the 13C-DNA revealed that bacteria related Sciences, Foresterhill, Aberdeen AB25 2ZD, UK to the genera Methylocella, Methylocapsa, Methylocystis and Rhodoblastus had assimilated the 13C-labelled substrates, which suggested that moderately 3 Department of Biological Sciences, University of acidophilic methylotroph populations were active in the microcosms. Essex, Wivenhoe Park, Enrichments targeted towards the active proteobacterial CH3OH utilizers were Colchester, Essex CO4 3SQ, successful, although none of these bacteria were isolated into pure culture. A UK parallel analysis of genes encoding the key enzymes methanol dehydrogenase 4 Department of Biology, and particulate methane monooxygenase reflected the 16S rDNA analysis, but University of York, PO Box 373, YO10 5YW, UK unexpectedly revealed sequences related to the ammonia monooxygenase of ammonia-oxidizing bacteria (AOB) from the β-subclass of the Proteobacteria.
    [Show full text]
  • Adaptive Laboratory Evolution Enhances Methanol Tolerance and Conversion in Engineered Corynebacterium Glutamicum
    ARTICLE https://doi.org/10.1038/s42003-020-0954-9 OPEN Adaptive laboratory evolution enhances methanol tolerance and conversion in engineered Corynebacterium glutamicum Yu Wang 1, Liwen Fan1,2, Philibert Tuyishime1, Jiao Liu1, Kun Zhang1,3, Ning Gao1,3, Zhihui Zhang1,3, ✉ ✉ 1234567890():,; Xiaomeng Ni1, Jinhui Feng1, Qianqian Yuan1, Hongwu Ma1, Ping Zheng1,2,3 , Jibin Sun1,3 & Yanhe Ma1 Synthetic methylotrophy has recently been intensively studied to achieve methanol-based biomanufacturing of fuels and chemicals. However, attempts to engineer platform micro- organisms to utilize methanol mainly focus on enzyme and pathway engineering. Herein, we enhanced methanol bioconversion of synthetic methylotrophs by improving cellular tolerance to methanol. A previously engineered methanol-dependent Corynebacterium glutamicum is subjected to adaptive laboratory evolution with elevated methanol content. Unexpectedly, the evolved strain not only tolerates higher concentrations of methanol but also shows improved growth and methanol utilization. Transcriptome analysis suggests increased methanol con- centrations rebalance methylotrophic metabolism by down-regulating glycolysis and up- regulating amino acid biosynthesis, oxidative phosphorylation, ribosome biosynthesis, and parts of TCA cycle. Mutations in the O-acetyl-L-homoserine sulfhydrylase Cgl0653 catalyzing formation of L-methionine analog from methanol and methanol-induced membrane-bound transporter Cgl0833 are proven crucial for methanol tolerance. This study demonstrates the importance of
    [Show full text]
  • Isolation, Characterization and Substrate-Transport Studies of a New, Unique Methylotroph
    RICE UNIVERSITY ISOLATION, CHARACTERIZATION AND SUBSTRATE-TRANSPORT STUDIES OF A NEW, UNIQUE METHYLOTROPH by Thomas Alan Keuer A THESIS SUBMITTED IN PARTIAL FULFULLMENT OF THE REQUIREMENTS FOR THE DEGREE Master of Science APPROVED, THESIS COMMITTEE: E. Terry Papoutsakis, Assistant Professor of Chemical Engineering LarryOf. Mclntire, Professor and Chairman of Chemical Engineering <03^ ' Roger Storck, Professor of Biology Houston, Texas April, 1984 3 1272 00289 0232 ABSTRACT Keuer, Thomas A. M.S. Rice University, April 1984. Isolation, Characterization and Substrate-Transport Studies of a New, Unique Methylotroph. Major Professor: E. T. Papoutsakis. Methylotrophic bacteria which assimilate carbon via the Ribulose Monophosphate Pathway are bioenergetically superior to other methylotrophs. The dehydrogenases which catalyze the oxidation of formaldehyde to formate and formate to CO2 in RMP bacteria produce much of the ATP required for biosynthesis. A strain, designated T15, has been isolated on the basis of high In vitro activities of the above two key enzymes, and has been biochemically characterized. The new strain exhibits high yields (up to 0.63 g cells/g MeOH) and growth rates (up to 0.46 hr“^) in batch culture? however, the yields and growth rates in continuous culture are significantly lower. Study of the transport mechanisms has provided valuable insight into the relationship between substrate uptake and the growth characteristics of T15. Experi¬ ments with radiolabelled substrates have indicated that methanol enters the cells primarily by diffusion? consequently, the bacteria are not able to accumulate methanol internally in order to support efficient Ill continuous growth. Formaldehyde, on the other hand, is accumulated by an active transport system which depends on the A pH component of the membrane proton-motive force.
    [Show full text]
  • Bacterial Metabolism of Methylated Amines and Identification of Novel Methylotrophs in Movile Cave
    The ISME Journal (2015) 9, 195–206 & 2015 International Society for Microbial Ecology All rights reserved 1751-7362/15 www.nature.com/ismej ORIGINAL ARTICLE Bacterial metabolism of methylated amines and identification of novel methylotrophs in Movile Cave Daniela Wischer1, Deepak Kumaresan1,4, Antonia Johnston1, Myriam El Khawand1, Jason Stephenson2, Alexandra M Hillebrand-Voiculescu3, Yin Chen2 and J Colin Murrell1 1School of Environmental Sciences, University of East Anglia, Norwich, UK; 2School of Life Sciences, University of Warwick, Coventry, UK and 3Department of Biospeleology and Karst Edaphobiology, Emil Racovit¸a˘ Institute of Speleology, Bucharest, Romania Movile Cave, Romania, is an unusual underground ecosystem that has been sealed off from the outside world for several million years and is sustained by non-phototrophic carbon fixation. Methane and sulfur-oxidising bacteria are the main primary producers, supporting a complex food web that includes bacteria, fungi and cave-adapted invertebrates. A range of methylotrophic bacteria in Movile Cave grow on one-carbon compounds including methylated amines, which are produced via decomposition of organic-rich microbial mats. The role of methylated amines as a carbon and nitrogen source for bacteria in Movile Cave was investigated using a combination of cultivation studies and DNA stable isotope probing (DNA-SIP) using 13C-monomethylamine (MMA). Two newly developed primer sets targeting the gene for gamma-glutamylmethylamide synthetase (gmaS), the first enzyme of the recently-discovered indirect MMA-oxidation pathway, were applied in functional gene probing. SIP experiments revealed that the obligate methylotroph Methylotenera mobilis is one of the dominant MMA utilisers in the cave. DNA-SIP experiments also showed that a new facultative methylotroph isolated in this study, Catellibacterium sp.
    [Show full text]
  • Adverse Effect of the Methanotroph Methylocystis Sp. M6 on the Non-Methylotroph Microbacterium Sp
    J. Microbiol. Biotechnol. (2018), 28(10), 1706–1715 https://doi.org/10.4014/jmb.1804.04015 Research Article Review jmb Adverse Effect of the Methanotroph Methylocystis sp. M6 on the Non-Methylotroph Microbacterium sp. NM2 So-Yeon Jeong1, Kyung-Suk Cho2, and Tae Gwan Kim1* 1Department of Microbiology, Pusan National University, Pusan 46241, Republic of Korea 2Department of Environmental Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea Received: April 12, 2018 Revised: July 19, 2018 Several non-methylotrophic bacteria have been reported to improve the growth and activity of Accepted: August 23, 2018 methanotrophs; however, their interactions remain to be elucidated. We investigated the First published online interaction between Methylocystis sp. M6 and Microbacterium sp. NM2. A batch co-culture August 24, 2018 experiment showed that NM2 markedly increased the biomass and methane removal of M6. *Corresponding author qPCR analysis revealed that NM2 enhanced both the growth and methane-monooxygenase Phone: +82-515102268; gene expression of M6. A fed-batch experiment showed that co-culture was more efficient in Fax: +82-515141778; -1 -1 E-mail: [email protected] removing methane than M6 alone (28.4 vs. 18.8 µmol·l ·d ), although the biomass levels were similar. A starvation experiment for 21 days showed that M6 population remained stable while NM2 population decreased by 66% in co-culture, but the results were opposite in pure cultures, indicating that M6 may cross-feed growth substrates from NM2. These results indicate that M6 apparently had no negative effect on NM2 when M6 actively proliferated with methane. Interestingly, a batch experiment involving a dialysis membrane indicates that physical proximity between NM2 and M6 is required for such biomass and methane removal enhancement.
    [Show full text]
  • Methylotrophs and Methylotroph Communities
    caister.com/meth Methylotrophs and Methylotroph Communities https://doi.org/10.21775/9781912530045 Edited by Ludmila Chistoserdova Department of Chemical Engineering University of Washington Seattle WA USA Caister Academic Press Date: 15:45 Thursday 21 March 2019 UNCORRECTED PROOF File: Methylotrophs 3P caister.com/meth Copyright © 2019 Caister Academic Press Norfolk, UK www.caister.com British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library ISBN: 978-1-912530-04-5 (hardback) ISBN: 978-1-912530-05-2 (ebook) Description or mention of instrumentation, software, or other products in this book does not imply endorsement by the author or publisher. The author and publisher do not assume responsibility for the validity of any products or procedures mentioned or described in this book or for the consequences of their use. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the publisher. No claim to original U.S. Government works. Cover design adapted with permission from Dr Kelly C. Wrighton, Fort Collins, CO, USA Ebooks Ebooks supplied to individuals are single-user only and must not be reproduced, copied, stored in a retrieval system, or distributed by any means, electronic, mechanical, photocopying, email, internet or otherwise. Ebooks supplied to academic libraries, corporations, government organizations, public libraries, and school libraries are subject to the terms and conditions specified by the supplier. Date: 15:45 Thursday 21 March 2019 UNCORRECTED PROOF File: Methylotrophs 3P caister.com/meth Contents Preface v 1 Methanotrophy – Environmental, Industrial and Medical Applications 1 Jeremy D.
    [Show full text]
  • Specialized Metabolites from Methylotrophic Proteobacteria Aaron W
    Specialized Metabolites from Methylotrophic Proteobacteria Aaron W. Puri* Department of Chemistry and the Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, UT, USA. *Correspondence: [email protected] htps://doi.org/10.21775/cimb.033.211 Abstract these compounds and strategies for determining Biosynthesized small molecules known as special- their biological functions. ized metabolites ofen have valuable applications Te explosion in bacterial genome sequences in felds such as medicine and agriculture. Con- available in public databases as well as the availabil- sequently, there is always a demand for novel ity of bioinformatics tools for analysing them has specialized metabolites and an understanding of revealed that many bacterial species are potentially their bioactivity. Methylotrophs are an underex- untapped sources for new molecules (Cimerman- plored metabolic group of bacteria that have several cic et al., 2014). Tis includes organisms beyond growth features that make them enticing in terms those traditionally relied upon for natural product of specialized metabolite discovery, characteriza- discovery, and recent studies have shown that tion, and production from cheap feedstocks such examining the biosynthetic potential of new spe- as methanol and methane gas. Tis chapter will cies indeed reveals new classes of compounds examine the predicted biosynthetic potential of (Pidot et al., 2014; Pye et al., 2017). Tis strategy these organisms and review some of the specialized is complementary to synthetic biology approaches metabolites they produce that have been character- focused on activating BGCs that are not normally ized so far. expressed under laboratory conditions in strains traditionally used for natural product discovery, such as Streptomyces (Rutledge and Challis, 2015).
    [Show full text]
  • Difference Between Chemoorganotrophic and Obligate Autotroph
    Difference Between Chemoorganotrophic And Obligate Autotroph Cary underbidding misanthropically. Ulric often demise parlous when conjugated Ford mollycoddles indistinctly and domes her cyma. Lew often descants unfeignedly when isocheimic Tedie turn-offs designedly and Judaizing her accentors. No mechanism for anaerobic metabolism in conjunction with a common when algae, along the catabolism ofaromatic compounds provide evidence was a difference between trees inferred with the four genera have a consensus approach to The physiological characteristics of use different types of bacteria and their interactions. CO2 stimulates the chemoorganotrophic growth of both ammonia oxidizers and the. Chemoorganotrophic Definition of Chemoorganotrophic by. While Acidithiobacillus ferrooxidans growing on FeSO4 would depict an obligate aerobe. A fundamental metabolic distinction is between autotrophs and heterotrophs. Cthe intermediate steps of autotroph and only select multiple curvature and to safely place in each student need to a membrane that can be essentially the deep. The facultative autotroph also oxidizes a ridicule of organic compounds such. Bacterial Metabolism Medical Microbiology NCBI Bookshelf. Interestingly the amount cure the carboxylase in M capsulatus in chemostat culture. Facultative autotroph Can reproduce as autotroph if they must first better as. Learning Objectives Differentiate photoautotrophs from photoheterotrophs. Electron Transport Chain. Ecology of Cyanobacteria II Their Diversity in Space faculty Time. A Photographic Atlas for the Microbiology Laboratory. 5 Algae Biology LibreTexts. MB302 Oregon State University. Autotroph t-trf An organism that manufactures its own value from inorganic substances such high carbon dioxide and ammonia Most autotrophs such clean green plants certain algae and photosynthetic bacteria use ticket for energy. Ment was achieved by comparison by the labour count helpless the pervert of Thiobacillus A2 obtained on.
    [Show full text]
  • Evolution of Methanotrophy in the Beijerinckiaceae&Mdash
    The ISME Journal (2014) 8, 369–382 & 2014 International Society for Microbial Ecology All rights reserved 1751-7362/14 www.nature.com/ismej ORIGINAL ARTICLE The (d)evolution of methanotrophy in the Beijerinckiaceae—a comparative genomics analysis Ivica Tamas1, Angela V Smirnova1, Zhiguo He1,2 and Peter F Dunfield1 1Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada and 2Department of Bioengineering, School of Minerals Processing and Bioengineering, Central South University, Changsha, Hunan, China The alphaproteobacterial family Beijerinckiaceae contains generalists that grow on a wide range of substrates, and specialists that grow only on methane and methanol. We investigated the evolution of this family by comparing the genomes of the generalist organotroph Beijerinckia indica, the facultative methanotroph Methylocella silvestris and the obligate methanotroph Methylocapsa acidiphila. Highly resolved phylogenetic construction based on universally conserved genes demonstrated that the Beijerinckiaceae forms a monophyletic cluster with the Methylocystaceae, the only other family of alphaproteobacterial methanotrophs. Phylogenetic analyses also demonstrated a vertical inheritance pattern of methanotrophy and methylotrophy genes within these families. Conversely, many lateral gene transfer (LGT) events were detected for genes encoding carbohydrate transport and metabolism, energy production and conversion, and transcriptional regulation in the genome of B. indica, suggesting that it has recently acquired these genes. A key difference between the generalist B. indica and its specialist methanotrophic relatives was an abundance of transporter elements, particularly periplasmic-binding proteins and major facilitator transporters. The most parsimonious scenario for the evolution of methanotrophy in the Alphaproteobacteria is that it occurred only once, when a methylotroph acquired methane monooxygenases (MMOs) via LGT.
    [Show full text]
  • View PDF Version
    RSC Advances View Article Online REVIEW View Journal | View Issue Guidance for engineering of synthetic methylotrophy based on methanol metabolism in Cite this: RSC Adv.,2017,7,4083 methylotrophy Wenming Zhang, Ting Zhang, Sihua Wu, Mingke Wu, Fengxue Xin, Weiliang Dong, Jiangfeng Ma, Min Zhang and Min Jiang* Methanol is increasingly becoming an attractive substrate for production of different metabolites, such as commodity chemicals, and biofuels via biological conversion, due to the increment of annual production capacity and decrement of prices. In recent years, genetic engineering towards native menthol utilizing organisms – methylotrophy has developed rapidly and attracted widespread attention. Therefore, it is vital to elucidate the distinct pathways that involve methanol oxidation, formaldehyde assimilation and disassimilation in the different methylotrophies for future synthetic work. In addition, this will also help to genetically construct some new and non-native methylotrophies. This review summarizes the Received 19th November 2016 Creative Commons Attribution-NonCommercial 3.0 Unported Licence. current knowledge about the methanol metabolism pathways in methylotrophy, discusses and Accepted 26th December 2016 compares different pathways on methanol utilization, and finally presents the strategies to integrate DOI: 10.1039/c6ra27038g the methanol metabolism with other chemicals, biofuels or other high value-added product formation www.rsc.org/advances pathways. 1. Introduction million tons per year and an expected annual growth rate in the range of 10–20%, a methanol-based bioeconomy has been With the rapid growth of the world population and develop- proposed.3 Especially recently, with the rise of the methanol This article is licensed under a ment of industry and society, energy demand is dramatically production process, the price of methanol steadily declined.
    [Show full text]
  • Bioconversion of Methanol Into Value- Added Chemicals in Native and Synthetic Methylotrophs
    Bioconversion of Methanol into Value- added Chemicals in Native and Synthetic Methylotrophs Min Zhang1, Xiao-jie Yuan1, Cong Zhang1, Li-ping Zhu1, Xu-hua Mo1, Wen-jing Chen1 and Song Yang1,2* 1School of Life Science, Qingdao Agricultural University, Shandong Province Key Laboratory of Applied Mycology, and Qingdao International Center on Microbes Utilizing Biogas, Qingdao, China. 2Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin, China. *Correspondence: [email protected] htps://doi.org/10.21775/cimb.033.225 Abstract production of value-added chemicals. In particular, Methanol, commercially generated from methane, methanol is an important one-carbon (C1) feed- is a renewable chemical feedstock that is highly sol- stock that can be generated from either synthesis uble, relatively inexpensive, and easy to handle. Te gas (a mixture of CO and H2) or from biogas, concept of native methylotrophic bacteria serving assuming that large quantities of this feedstock as whole cell catalysts for production of chemicals could be produced at relatively low market price and materials using methanol as a feedstock is (Clomburg et al., 2017; Yang et al., 2018). Methylotrophic highly atractive. In recent years, the available omics bacteria are a diverse group of microbes that can use data for methylotrophic bacteria, especially for reduced C1 compounds such as methanol and Methylobacterium extorquens, the best-characterized methane as sole sources of both energy and carbon model methylotroph, have provided a
    [Show full text]
  • Revisiting Methylotrophy: the Impact of Lanthanides and Lanthanide-Dependent Enzymes on the Methylotrophic Metabolic Network
    REVISITING METHYLOTROPHY: THE IMPACT OF LANTHANIDES AND LANTHANIDE-DEPENDENT ENZYMES ON THE METHYLOTROPHIC METABOLIC NETWORK By Anna Frances Huff A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of Microbiology and Molecular Genetics – Master of Science 2017 ABSTRACT REVISITING METHYLOTROPHY: THE IMPACT OF LANTHANIDES AND LANTHANIDE-DEPENDENT ENZYMES ON THE METHYLOTROPHIC METABOLIC NETWORK By Anna Frances Huff The recent discovery of lanthanide (Ln3+)-dependent enzymes renewed interest in methylotrophs, although the impact of these enzymes is not understood. In Methylobacterium extorquens AM1, the Ca2+-dependent MxaFI canonically oxidizes methanol to formaldehyde. The tetrahydromethanopterin (H4MPT) pathway oxidizes formaldehyde to formate. Formate is oxidized to CO2 by formate dehydrogenases (FDH) or partially reduced and assimilated. The genome of M. extorquens AM1 codes for three known Ln3+-dependent genes: xoxF, xoxF2, and exaF. XoxF may oxidize both methanol and formaldehyde in some organisms while ExaF demonstrated efficient activity with formaldehyde in the presence of La3+ providing a potential alternative to the H4MPT pathway. RNAseq data provided by Dr. Nathan Good found downregulation of mxa genes and the first gene of the H4MPT pathway, fae, and upregulation of xoxF, xoxF2, and exaF in the presence of La3+ suggesting changes to carbon distribution. I found a sharp decrease in accumulation formaldehyde and fourfold increase in accumulation of formate in the presence of La3+ and hypothesized this was due to the activity of Ln3+ enzymes. I measured the minimum inhibitory concentration (MIC) to methanol metabolism and found decreased sensitivity of a ∆fae mutant from 10 mM to more than 125 mM in the presence of La3+.
    [Show full text]