Methanothermobacter thermautotrophicus strain and variants thereof

Abstract

Provided herein is an isolated Methanothermobacter microorganism that is (a) a microorganism of Methanothermobacter thermautotrophicus strain UC 120910, deposited on Dec. 21, 2010, with the American Type Culture Collection (ATCC) under ATCC® Patent Deposit Designation No. PTA-11561, (b) a variant of the microorganism of Methanothermobacter thermautotrophicus strain UC 120910, or (c) a progeny of the microorganism of Methanothermobacter thermautotrophicus strain UC 120910, wherein the variant or progeny retains the phenotypic characteristics of the microorganism of Methanothermobacter thermautotrophicus strain UC 120910. Also provided herein is a substantially pure culture or monoculture comprising the Methanothermobacter microorganism of the disclosure. A system for converting electric power into methane, comprising a biological reactor having at least a cathode, an anode, a presently disclosed Methanothermobacter microorganism, water, and carbon dioxide, and method of using the system for converting electricity into methane are further provided herein.

1 .- 134 . (canceled) 
     
     
         135 . A microorganism produced by a method comprising culturing a microorganism of  Methanothermobacter thermautotrophicus  strain UC 120910, deposited on Dec. 21, 2010, with the American Type Culture Collection (ATCC®) under ATCC® Patent Deposit Designation No. PTA-11561 in a bioreactor, wherein a gas mixture comprising hydrogen gas and carbon dioxide gas is supplied to the bioreactor, wherein the microorganism produced by the method retains the methane production efficiency per molecule of carbon dioxide (CO 2 ) of the microorganism of ATCC® Patent Deposit Designation No. PTA-11561, which is at least or about 25 CO 2  molecules converted to methane per CO 2  molecule converted to cellular material. 
     
     
         136 . The microorganism of claim  1 , which:
 a. returns to at least 80% of the methane productivity level in the operating state within 20 minutes, after an exposure of at least 10 minutes to oxygen (e.g. oxygen in ambient air) or carbon monoxide.   b. exhibits the methane production efficiency while exhibiting a doubling time of at least or about 72 hours.   c. exhibits the methane production efficiency for at least 30 days.   d. survives in a stationary phase or a nearly stationary phase having a doubling time of at least or about 72 hours for at least 30 days.   e. returns to at least 80% of the methane productivity level in the operating state within 20 minutes of re-supplying hydrogen or electricity, after being in a dormant state for at least 2 hours as induced by interrupting or ceasing hydrogen supply or electricity.   
     
     
         137 . A culture medium comprising a microorganism of claim  1  and a gas mixture comprising hydrogen gas and carbon dioxide gas. 
     
     
         138 . The culture medium of claim  3 , wherein the culture medium is in a bioreactor and the gas mixture is supplied to the bioreactor. 
     
     
         139 . A culture comprising a microorganism of claim  1 . 
     
     
         140 . A method of producing methane from carbon dioxide, comprising supplying a gas mixture comprising hydrogen gas and carbon dioxide gas to a culture of claim  5 . 
     
     
         141 . A method for producing a progeny of a microorganism of  Methanothermobacter thermautotrophicus  strain UC 120910, deposited on Dec. 21, 2010, with the American Type Culture Collection (ATCC®) under ATCC® Patent Deposit Designation No. PTA-11561, the method comprising reproducing or multiplying a microorganism of  Methanothermobacter thermautotrophicus  strain UC 120910. 
     
     
         142 . A system for producing methane from carbon dioxide, comprising a supply of carbon dioxide, a source of reducing power, and methanogenic microorganisms cultured at a temperature of about 50 degrees C. or higher and a pH of about 8 to about 10 or about 8.5 to about 11, optionally, wherein the methanogenic microorganisms are cultured at a redox potential below −100 mV. 
     
     
         143 . The system of  claim 142 , wherein (i) the source of reducing power comprises hydrogen gas, (ii) the supply of carbon dioxide is carbon dioxide from an industrial process or carbon dioxide from the environment, or (iii), both (i) and (ii). 
     
     
         144 . The system of  claim 142 , wherein the methanogenic microorganisms exhibit a methane production efficiency that is at least or about 25 CO 2  molecules converted to methane per CO2 molecule converted to cellular material, produces at least or about 96 molecules of methane per 100 molecules of carbon dioxide supplied to the microorganisms, and/or produces at least or about 17 grams of methane from carbon dioxide per 1 gram of cellular material produced from carbon dioxide. 
     
     
         145 . The system of  claim 142 , wherein the methanogenic microorganisms are capable of returning to at least 80% of the methane productivity in the operating state within 20 minutes of re-supplying hydrogen or electricity after being in a dormant state for at least 2 hours. 
     
     
         146 . The system of  142 , wherein the microorganisms are hydrogenotrophic methanogenic microorganisms. 
     
     
         147 . The system of  claim 142 , wherein the microorganisms belong to the genus  Methanothermobacter.    
     
     
         148 . The system of  claim 147 , wherein the microorganisms are microorganisms of the species  thermautotrophicus  or of the species  marburgensis.    
     
     
         149 . The system of  claim 142 , wherein the methanogenic microorganisms are cultured in a bioreactor, optionally wherein the bioreactor has a total capacity of about 750,000 gal. 
     
     
         150 . A method of culturing a methanogenic microorganism for methane production, comprising culturing a methanogenic microorganism under conditions comprising a temperature of 50 degrees C. or higher, an alkaline pH, and a pressure within a range from about 0.5 atmospheres to about 500 atmospheres. 
     
     
         151 . The method of  claim 150 , wherein the temperature is about 50 degrees C. to about 100 degrees C. 
     
     
         152 . The method of  claim 151 , wherein the temperature is about 60 degrees C. to about 80 degrees C. 
     
     
         153 . The method of  claim 150 , wherein the pH is about 8.0, about 8.5, about 9.0, or about 9.5.