Polyhydroxyalkanoate compositions and microbial cultures for making the same
Embodiments of the invention relate to the microbial production of polyhydroxyalkanoic acids, or polyhydroxyalkanoates (PHA), from substrates which cannot be used as a source of carbon and/or energy for microbial growth or PHA synthesis and which have microbial and environmental toxicity. According to one embodiment of the invention, a process for the production of PHA is provided wherein an enzyme such as methane monooxygenase is used to convert volatile organic compounds into PHA through the use of microorganisms that are unable to use volatile organic compounds as a source of carbon for growth or PHA production.
1. A polyhydroxyalkanoate (PHA) composition comprising a polyhydroxyalkanoate and cell components from methane-monooxygenase-microorganisms (MMO-microorganisms) and PHA microorganisms wherein said MMO-microorganisms are capable of oxidizing volatile organic compounds (VOCs) into MMO-oxidized forms of the VOCs, wherein said PHA microorganisms are capable of using the MMO-oxidized forms of the VOCs as a source of carbon for PHA production, and wherein said MMO-microorganisms and said PHA microorganisms are different microorganisms.
2. The composition of claim 1 , wherein said polyhydroxyalkanoate comprises a carbon backbone wherein at least one of said carbons comprising said backbone is derived from a non-methane organic compound that is oxidized by methane monooxygenase.
3. The composition of claim 2 , wherein said polyhydroxyalkanoate is selected from the group consisting of polyhydroxybutyrate (PHB), polyhydroxybutyrate-covalerate (PHBV), and polyhydroxyhexanoate (PHHx).
4. The composition of claim 1 , wherein said cell components are non-polyhydroxyalkanoate materials derived from PHA microorganisms and MMO-microorganisms.
5. The composition of claim 1 , wherein said PHA microorganisms are selected form the group consisting of naturally-occurring and genetically-engineered microorganisms, wherein the microorganisms are bacteria or fungi capable of using the MMO-oxidized form of the VOCs as a source of carbon for PHA production.
6. The composition of claim 2 , wherein said non-methane organic compound is a volatile organic compound.
7. The composition of claim 6 , wherein said VOCs are selected from the group consisting of highly evaporative, carbon-based chemical substances; chemical compounds that are gases at room temperature and contain carbon; and/or compounds comprising carbon which participate in atmospheric photochemical reactions.
8. The composition of claim 6 , wherein said VOCs are selected from the group consisting of hydrocarbons, halocarbons, and oxygenates.
9. The composition of claim 6 , wherein said VOCs are selected from the group consisting of: methylene chloride (dichloromethane); ethane; 1,1,1-trichloroethane (methyl chloroform); 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113); trichlorofluoromethane (CFC-11); dichlorodifluoromethane (CFC-12); chlorodifluoromethane (HCFC-22); trifluoromethane (HFC-23); 1,2-dichloro-1,1,2,2-tetrafluoroethane (CFC-114); chloropentafluoroethane (CFC-115); 1,1,1-trifluoro 2,2-dichloroethane (HCFC-123); 1,1,1,2-tetrafluoroethane (HFC-134a); 1,1-dichloro-1-fluoroethane (HCFC-141b); 1-chloro-1,1-difluoroethane (HCFC-142b); 2-chloro-1,1,1,2-tetrafluoroethane (HCFC-124); pentafluoroethane (HFC-125); 1,1,2,2-tetrafluoroethane (HFC-134); 1,1,1-trifluoroethane (HFC-143a); 1,1-difluoroethane (HFC-152a); parachlorobenzotrifluoride (PCBTF); cyclic, branched, or linear completely methylated siloxanes; acetone; perchloroethylene (tetrachloroethylene); propane; 3,3-dichloro-1,1,1,2,2-pentafluoropropane (HCFC-225ca); 1,3-dichloro-1,1,2,2,3-pentafluoropropane (HCFC-225cb); 1,1,1,2,3,4,4,5,5,5-decafluoropentane (HFC43-10mee); difluoromethane (HFC-32); ethylfluoride (HFC-161); 1,1,1,3,3,3-hexafluoropropane (HFC-236fa); 1,1,2,2,3-pentafluoropropane (HFC-245ca); 1,1,2,3,3-pentafluoropropane (HFC-245ea); 1,1,1,2,3-pentafluoropropane (HFC-245eb); 1,1,1,3,3-pentafluoropropane (HFC-245 fa); 1,1,1,2,3,3-hexafluoropropane (HFC-236ea); 1,1,1,3,3-pentafluorobutane (HFC-365mfc); chlorofluoromethane (HCFC-31); 1-chloro-1-fluoroethane (HCFC-151a); 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a); butane; 1,1,1,2,2,3,3,4,4-nonafluoro-4-methoxy-butane (C 4 F 9 OCH 3 ); 2-(difluoromethoxymethyl)-1,1,1,2,3,3,3-heptafluoropropane ((CF 3 ) 2 CFCF 2 OCH 3 ); 1-ethoxy-1,1,2,2,3,3,4,4,4-nonafluorobutane (C 4 F 9 OC 2 H 5 ); 2-(ethoxydifluoromethyl)-1,1,1,2,3,3,3-heptafluoropropane ((CF 3 ) 2 CFCF 2 OC 2 H 5 ); methyl acetate and perfluorocarbon compounds which fall into these classes: (i) cyclic, branched, or linear, completely fluorinated alkanes; (ii) cyclic, branched, or linear, completely fluorinated ethers with no unsaturations; (iii) cyclic, branched, or linear, completely fluorinated tertiary amines with no unsaturations; and (iv) sulfur containing perfluorocarbons with no unsaturations and with sulfur bonds only to carbon and fluorine.