Project description:Eubacterium limosum ATCC 8486 makes acetate and butyrate from various substrates and is found in the human intestine. The proteome of lactate-grown Eubacterium limosum was obtained in order to identify enzymes required for growth on this substrate, in particular to identify components that are unique to growth on lactate in comparison to other substrates for acetogenesis.
Project description:Eubacterium limosum ATCC 8486 makes acetate and butyrate from various substrates and is found in the human intestine. The proteome of L-carnitine-grown Eubacterium limosum was obtained in order to identify enzymes required for growth on L-carnitine, in particular to identify components that are unique to growth on L-carnitine in comparison to other substrates for acetogenesis, such as lactic acid. L-carnitine and derviatives are converted to trimethylamine (TMA) by certain members of the gut microbiome, metabolism of TMA is now tied to progression of cardiovascular disease. Demethylation of carnitine is observed during growth of Eubacterium limosum on this substrate, and does not produce TMA. Carnitine demethylation by organisms like Eubacterium limosum could lessen TMA production in the gut, thereby lessening the propensity towards atherorsclerosis caused by metabolism of TMA in the body. The carnitine proteome led to the description of a carnitine:tetrahydrofolate methyltransferase system. The key carnitine demethylating enzyme is a member of the widespread TMA methyltransferase protein superfamily.
Project description:Eubacterium limosum ATCC 8486 makes acetate and butyrate from various substrates and is found in the human intestine. The proteome of gamma-butyrobetaine -grown Eubacterium limosum was obtained in order to identify enzymes required for growth on gamma-butyrobetaine, in particular to identify components that are unique to growth on gamma-butyrobetaine in comparison to other substrates for acetogenesis, such as lactic acid, L-carnitine, or proline betaine. Gamma-butyrobetaine is converted to trimethylamine (TMA) by certain members of the gut microbiome. Subsequent liver metabolism of TMA is now tied to progression of cardiovascular disease. Demethylation of gamma-butyrobetaine is observed during growth of Eubacterium limosum on this substrate, and does not produce TMA. Gamma-butyrobetaine demethylation by organisms like Eubacterium limosum could lessen TMA production in the gut, thereby lessening the propensity towards atherosclerosis caused by metabolism of TMA in the body. This proteome led to discovery of gamma-butyrobetaine:tetrahydrofolate methyltransferase system. The key gamma-butyrobetaine demethylating enzyme is a member of the widespread TMA methyltransferase protein superfamily.
Project description:Proline betaine, and to a much lesser extent, N-methyl L-proline, are found in citrus fruits and often present in the human metabolome. However, most of the N-methyl L-proline found in an animal model metabolome is produced by the microbiota, yet organisms and enzymes capable of producing N-methyl proline in the anoxic intestine have been unknown. The anaerobe Eubacterium limosum ATCC 8486 makes acetate and butyrate from various substrates and is found in the human intestine. We found that this organism demethylates proline betaine and excretes N-methyl proline during growth. The proteome of proline betaine-grown Eubacterium limosum was obtained in order to identify enzymes required for growth on proline, in particular to identify components that are unique to growth on proline in comparison to other substrates for acetogenesis, such as lactic acid. Comparison of the proteomes of the bacteria on proline betaine and lactic acid led to identification of the proteins involved in a proline betaine:tetrahydrofolate methyltransferase system which was biochemically verified. The key proline betaine demethylating enzyme is a member of the widespread TMA methyltransferase protein superfamily.