title: A methanotroph-based biorefinery: Potential scenarios for generating multiple products from a single fermentation.
abstract: Methane, a carbon source for methanotrophic bacteria, is the principal component of natural gas and is produced during anaerobic digestion of organic matter (biogas). Methanotrophs are a viable source of single cell protein (feed supplement) and can produce various products, since they accumulate osmolytes (e.g. ectoine, sucrose), phospholipids (potential biofuels) and biopolymers (polyhydroxybutyrate, glycogen), among others. Other cell components, such as surface layers, metal chelating proteins (methanobactin), enzymes (methane monooxygenase) or heterologous proteins hold promise as future products. Here, scenarios are presented where ectoine, polyhydroxybutyrate or protein G are synthesised as the primary product, in conjunction with a variety of ancillary products that could enhance process viability. Single or dual-stage processes and volumetric requirements for bioreactors are discussed, in terms of an annual biomass output of 1000 tonnesyear(-1). Product yields are discussed in relation to methane and oxygen consumption and organic waste generation.
authors.affiliation: Centre for Solid Waste Bioprocessing, School of Civil Engineering, School of Chemical Engineering, The University of Queensland, Brisbane 4072, Australia. Electronic address: pjstrong@gmail.com.
authors.forename: P J
authors.initials: PJ
authors.lastname: Strong
authors.affiliation: Biology Department, San Diego State University, San Diego, CA 92182-4614, United States.
authors.forename: M
authors.initials: M
authors.lastname: Kalyuzhnaya
authors.affiliation: Calysta, 1140 O'Brien Drive, Menlo Park, CA 94025, United States.
authors.forename: J
authors.initials: J
authors.lastname: Silverman
authors.affiliation: Centre for Solid Waste Bioprocessing, School of Civil Engineering, School of Chemical Engineering, The University of Queensland, Brisbane 4072, Australia.
authors.forename: W P
authors.initials: WP
authors.lastname: Clarke
mesh_terms: D000818:Animals; D056804:Biofuels / Q000382:microbiology; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology; D005285:Fermentation / Q000502:physiology*; D006801:Humans; D008697:Methane / Q000378:metabolism*; D010105:Oxygenases; D000091402:Prohibitins; D064091:Waste Disposal Facilities; D018505:Waste Management / Q000379:methods*
chemical_list: D056804:Biofuels; C000717328:PHB protein, human; D000091402:Prohibitins; D010105:Oxygenases; C021555:methane monooxygenase; D008697:Methane
keywords: Biocatalysis; Biogas; Methanotroph; PHB; pMMO