Interspecies hydrogen transfer

Interspecies hydrogen transfer (IHT) is a form of interspecies electron transfer. It is a syntrophic process by which H₂ is transferred from one organism to another, particularly in the rumen and other anaerobic environments.

IHT was discovered between Methanobacillus omelianskii and an "S" organism in 1967 by Marvin Bryant, Eileen Wolin, Meyer Wolin, and Ralph Wolfe at the University of Illinois. It was shown in 1973 that this process occurs between Ruminococcus albus and Wolinella succinogenes.

This process affects the carbon cycle: methanogens can participate in interspecies hydrogen transfer combining H₂ and CO₂ to produce CH₄. Besides methanogens, acetogens, and sulfate-reducing bacteria can participate in IHT.