skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Bioconversion of methane to lactate by an obligate methanotrophic bacterium

Journal Article · · Scientific Reports
DOI:https://doi.org/10.1038/srep21585· OSTI ID:1239888
 [1];  [1];  [1];  [2];  [1];  [1]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. San Diego State Univ., San Diego, CA (United States)

Methane is the second most abundant greenhouse gas (GHG), with nearly 60% of emissions derived from anthropogenic sources. Microbial conversion of methane to fuels and value-added chemicals offers a means to reduce GHG emissions, while also valorizing this otherwise squandered high-volume, high-energy gas. However, to date, advances in methane biocatalysis have been constrained by the low-productivity and limited genetic tractability of natural methane-consuming microbes. Here, leveraging recent identification of a novel, tractable methanotrophic bacterium, Methylomicrobium buryatense, we demonstrate microbial biocatalysis of methane to lactate, an industrial platform chemical. Heterologous overexpression of a Lactobacillus helveticus L-lactate dehydrogenase in M. buryatense resulted in an initial titer of 0.06 g lactate/L from methane. Cultivation in a 5 L continuously stirred tank bioreactor enabled production of 0.8 g lactate/L, representing a 13-fold improvement compared to the initial titer. The yields (0.05 g lactate/g methane) and productivity (0.008 g lactate/L/h) indicate the need and opportunity for future strain improvement. Additionally, real-time analysis of methane utilization implicated gas-to-liquid transfer and/or microbial methane consumption as process limitations. This work opens the door to develop an array of methanotrophic bacterial strain-engineering strategies currently employed for biocatalytic sugar upgrading to “green” chemicals and fuels.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Sustainable Transportation Office. Bioenergy Technologies Office
Grant/Contract Number:
AC36-08GO28308
OSTI ID:
1239888
Report Number(s):
NREL/JA-5100-65849
Journal Information:
Scientific Reports, Vol. 6; Related Information: Scientific Reports; ISSN 2045-2322
Publisher:
Nature Publishing GroupCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 100 works
Citation information provided by
Web of Science

References (37)

Metabolic engineering in methanotrophic bacteria journal May 2015
Isolation and Characterization of Halotolerant Alkaliphilic Methanotrophic Bacteria from Tuva Soda Lakes journal November 1997
Accurate and reliable quantification of total microalgal fuel potential as fatty acid methyl esters by in situ transesterification journal February 2012
Microbial production of poly(hydroxybutyrate) from C1 carbon sources journal January 2013
Draft Genome Sequence of Methylomicrobium buryatense Strain 5G, a Haloalkaline-Tolerant Methanotrophic Bacterium journal June 2013
Envisioning the Bioconversion of Methane to Liquid Fuels journal February 2014
Efficient Production of L-Lactic Acid by Metabolically Engineered Saccharomyces cerevisiae with a Genome-Integrated L-Lactate Dehydrogenase Gene journal April 2005
Genetic Systems for Moderately Halo(alkali)philic Bacteria of the Genus Methylomicrobium book January 2011
Taxonomic Characterization of New Alkaliphilic and Alkalitolerant Methanotrophs from Soda Lakes of the Southeastern Transbaikal Region and description of Methylomicrobium buryatense sp.nov. journal January 2001
Cow power: the energy and emissions benefits of converting manure to biogas journal July 2008
Bioconversion of natural gas to liquid fuel: Opportunities and challenges journal May 2014
Intracellular localization of the particulate methane monooxygenase and methanol dehydrogenase in Methylomicrobium album BG8 journal July 2002
Glycolytic enzymes in mammalian spermatozoa. Activities and stabilities of hexokinase and phosphofructokinase in various fractions from sperm homogenates journal October 1971
Rethinking biological activation of methane and conversion to liquid fuels journal April 2014
Methane as a Resource: Can the Methanotrophs Add Value? journal March 2015
Heterotrophic bacteria growing in association with Methylococcus capsulatus (Bath) in a single cell protein production process journal June 2002
High-rate conversion of methane to methanol by Methylosinus trichosporium OB3b journal August 2011
Biocatalytic Conversion of Methane to Methanol as a Key Step for Development of Methane-Based Biorefineries journal December 2014
Wasted Food, Wasted Energy: The Embedded Energy in Food Waste in the United States journal August 2010
Expression of bacterial hemoglobin genes to improve astaxanthin production in a methanotrophic bacterium Methylomonas sp. journal November 2006
Identification and microbial production of a terpene-based advanced biofuel journal September 2011
Metabolic engineering of Yarrowia lipolytica for itaconic acid production journal November 2015
Recent advances in lactic acid production by microbial fermentation processes journal November 2013
Use of Transposon Promoter-Probe Vectors in the Metabolic Engineering of the Obligate Methanotroph Methylomonas sp. Strain 16a for Enhanced C40 Carotenoid Synthesis journal January 2007
Microbial production of lactic acid journal January 2015
Use of the tetracycline promoter for the tightly regulated production of a murine antibody fragment in Escherichia coli journal December 1994
L-lactic acid production from D-xylose with Candida sonorensis expressing a heterologous lactate dehydrogenase encoding gene journal August 2014
Lignin valorization through integrated biological funneling and chemical catalysis journal August 2014
Highly efficient methane biocatalysis revealed in a methanotrophic bacterium journal December 2013
Engineering and adaptive evolution of Escherichia coli for d-lactate fermentation reveals GatC as a xylose transporter journal September 2012
Genetic Tools for the Industrially Promising Methanotroph Methylomicrobium buryatense journal December 2014
The Expanding World of Methylotrophic Metabolism journal October 2009
Construction of the astaxanthin biosynthetic pathway in a methanotrophic bacterium Methylomonas sp. strain 16a journal January 2007
Search for Methanotrophic Producers of Exopolysaccharides journal November 2001
Building carbon–carbon bonds using a biocatalytic methanol condensation cycle journal October 2014
Control of Redox Balance by the Stringent Response Regulatory Protein Promotes Antioxidant Defenses of Salmonella journal September 2010
Genome Sequence of the Haloalkaliphilic Methanotrophic Bacterium Methylomicrobium alcaliphilum 20Z journal December 2011

Cited By (16)

Metabolic engineering of methanotrophs and its application to production of chemicals and biofuels from methane: Biofuel energy consumption-Economic growth relationship: An empirical investigation of Brazil journal August 2016
Building a genome engineering toolbox in nonmodel prokaryotic microbes journal May 2018
Biological conversion of methane to chemicals and fuels: technical challenges and issues journal February 2018
A modular approach for high-flux lactic acid production from methane in an industrial medium using engineered Methylomicrobium buryatense 5GB1 journal April 2018
Methane utilization in Methylomicrobium alcaliphilum 20ZR: a systems approach journal February 2018
Muconic acid production from methane using rationally-engineered methanotrophic biocatalysts journal January 2019
Methanol-based acetoin production by genetically engineered Bacillus methanolicus journal January 2020
Industrial biomanufacturing: The future of chemical production journal January 2017
Development of a CRISPR/Cas9 System for Methylococcus capsulatus In Vivo Gene Editing journal March 2019
Biological conversion of methane to putrescine using genome-scale model-guided metabolic engineering of a methanotrophic bacterium Methylomicrobium alcaliphilum 20Z journal June 2019
Efficient production of d-lactate from methane in a lactate-tolerant strain of Methylomonas sp. DH-1 generated by adaptive laboratory evolution journal September 2019
Role of the malic enzyme in metabolism of the halotolerant methanotroph Methylotuvimicrobium alcaliphilum 20Z journal November 2019
Fatty Acid Biosynthesis Pathways in Methylomicrobium buryatense 5G(B1) journal January 2017
Oxygen-limited metabolism in the methanotroph Methylomicrobium buryatense 5GB1C journal January 2017
Two Experimental Protocols for Accurate Measurement of Gas Component Uptake and Production Rates in Bioconversion Processes journal April 2019
A Prospective Study on the Fermentation Landscape of Gaseous Substrates to Biorenewables Using Methanosarcina acetivorans Metabolic Model journal August 2018