以氢为营养（Hydrogenotrophic）
| 底物利用类型和反应 Substrate utilization and reactions | 标准吉布斯自由能 △_G_0 (kj/mol CH4) | 产甲烷古菌 Methanogens | | --------------------------------------------- | --------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | +CO_2→CH_4+2H_2O$ | −135 | Methanobacteriales：_Methanobacterium_、_Methanobrevibacter_、_Methanothermobacter_、_Methanothermus_ Methanococcales：_Methanocaldococcus_、_Methanotorris_、_Methanococcus_、_Methanothermococcus_ Methanocellales：_Methanocella_ Methanomicrobiales：_Methanocalculus_、_Methanocorpusculum_、_Methanoculleus_、_Methanofollis_、_Methanogenium_、_Methanolacinia_、_Methanomicrobium_、_Methanoplanus_、_Methanolinea_、_Methanoregula_、_Methanosphaerula_ Methanosarcinales：_Methanosarcina_ Methanopyrales：_Methanopyrus_ | | →CH_4+3CO_2+2H_2O$ | −130 | Methanobacteriales：_Methanobacterium_、_Methanobrevibacter_、_Methanothermobacter_ Methanococcales：_Methanococcus_、_Methanothermococcus_、_Methanotorris_ Methanocellales：_Methanocella_ Methanomicrobiales：_Methanocalculus_、_Methanocorpusculum_、_Methanoculleus_、_Methanofollis_、_Methanogenium_、_Methanolacinia_、_Methanolinea_、_Methanomicrobium_、_Methanoplanus_、_Methanoregula_、_Methanosphaerula_、_Methanospirillum_ | | +CO_2→2CH_3COOH+CH_4$ | −112 | Methanomicrobiales：_Methanogenium_、_Methanofollis_ | | +4(CH_3)_2CHOH→CH_4+4CH_3COCH_3+ 2H_2O$ | −37 | Methanobacteriales：_Methanobacterium_ Methanomicrobiales：_Methanocorpusculum_、_Methanoculleus_、_Methanofollis_、_Methanogenium_、_Methanolacinia_ | | +2H_2O→CH_4+3CO_2$ | −196 | Methanobacteriales：_Methanothermobacter_ Methanosarcinales：_Methanosarcina_ |