|MadSci Network: Microbiology|
Sorry, I cannot give specific answers to your questions but I can generalize some. Without doing any research, I assume that Syntrophmonas is a component of the digestive tract of ruminants and as such, the oxidation of butryate to acetate (and even the further oxidation of acetate to C02 and water )is a reasonable source of ATP, which in turn can do whatever the organism needs to do for growth and survival. If hydrogen is a product of Syntrophomonas under rumen conditions, then this is presumably an activity essential to its survival and growth.
Similarly, among the several methanobacteria there may well be a member that can utilize hydrogen (or even carbon monoxide) in the production of methane.
As to whether any two microorganisms can thrive or even survive in an anaerobic digestor--this is a question the answer to which depends on the evironment in a given anaerobic digestor, such as pH, nutrients available, temperature, turnover rate, etc and so I don't think there is a definitive answer to your question. The answer then is "possibly". This is about the best I can offer.
J. R. D. McCormick
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