Energy Metabolism and Extracellular Electron Transfer of Methanosarcina and Methanothrix

doi:10.13560/j.cnki.biotech.bull.1985.2025-0997

Abstract

Abstract:

Aceticlastic methanogens are the primary drivers of methane production in natural environments, contributing approximately two-thirds of global biogenic methane. This review systematically summarizes the physiology, morphology, substrate utilization, core metabolic pathways, and electron transfer and energy conservation mechanisms of two representative aceticlastic methanogens—Methanosarcina and Methanothrix. We comprehensively compare their differences in acetate activation strategies, coenzyme regeneration pathways, and energy conservation modes, revealing their metabolic adaptations and ecological niche differentiation under varying environmental conditions. The review further highlights research progresses in extracellular electron transfer, including direct interspecies electron transfer, microbial electrochemical corrosion, and extracellular respiration, and elucidates their underlying molecular mechanisms and energy conservation strategies. This review provides an integrated perspective on the metabolic networks and electron flow regulation of aceticlastic methanogens and lays a theoretical foundation for future studies on their environmental adaptation and metabolic control.

Key words: aceticlastic methanogens, Methanosarcina, Methanothrix, electron transport chain, extracellular electron transfer, direct interspecies electron transfer

ZHOU Jin-jie, LI Meng. Energy Metabolism and Extracellular Electron Transfer of Methanosarcina and Methanothrix[J]. Biotechnology Bulletin, 2026, 42(2): 17-29.

Figures/Tables 3

References 83

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项目 Item		Ⅰ型甲烷八叠球菌 Type Ⅰ Methanosarcina	Ⅱ型甲烷八叠球菌 Type Ⅱ Methanosarcina	甲烷丝菌 Methanothrix
形态		不规则球形，直径0.8-4.0 μm，常形成多细胞团聚体		杆形，长2.0-6.0 μm，宽0.8-1.3 μm，包裹于管状鞘结构中
底物		乙酸，甲基化合物，H₂/CO₂，甲基化合物/H₂	乙酸，甲基化合物	乙酸
乙酸亲和力		低	低	高
生长速率		快	快	慢
乙酸降解关键酶		Ack， Pta	Ack， Pta	Acs
电子传递系统组成		Ech， Frh， Vht， Fpo， Hdr， Mtr	Rnf， MmcA， Fpo， Hdr， Mtr	Fpo， Hdr， Mtr
胞外电子传递
吸收电子	DIET	+	+	+
	Fe（0）	+	+	+
	316L stainless steel	+	NA¹	+
释放电子	Fe（Ⅲ）	+	+	NA¹
释放电子	AQDS	+	+	NA¹
代表种		M. barkeri	M. acetivorans	Mx. soehngenii

项目 Item		Ⅰ型甲烷八叠球菌 Type Ⅰ Methanosarcina	Ⅱ型甲烷八叠球菌 Type Ⅱ Methanosarcina	甲烷丝菌 Methanothrix
形态		不规则球形，直径0.8-4.0 μm，常形成多细胞团聚体		杆形，长2.0-6.0 μm，宽0.8-1.3 μm，包裹于管状鞘结构中
底物		乙酸，甲基化合物，H₂/CO₂，甲基化合物/H₂	乙酸，甲基化合物	乙酸
乙酸亲和力		低	低	高
生长速率		快	快	慢
乙酸降解关键酶		Ack， Pta	Ack， Pta	Acs
电子传递系统组成		Ech， Frh， Vht， Fpo， Hdr， Mtr	Rnf， MmcA， Fpo， Hdr， Mtr	Fpo， Hdr， Mtr
胞外电子传递
吸收电子	DIET	+	+	+
	Fe（0）	+	+	+
	316L stainless steel	+	NA¹	+
释放电子	Fe（Ⅲ）	+	+	NA¹
释放电子	AQDS	+	+	NA¹
代表种		M. barkeri	M. acetivorans	Mx. soehngenii

产甲烷古菌 Methanogen	电子供体细菌 Electro-donating bacteria	电子供体 Electron donor	产甲烷古菌DIET关键蛋白 Key protein DIET of methanogenic archaeon	参考文献 Reference
Type Ⅰ Methanosarcina
M. barkeri	Geobacter metallireducens Geobacter grbiciae Rhodoferax ferrireducens Rhodopseudomonas palustris¹	Ethanol Ethanol Glucose Light， thiosulfate	Fpo， HdrABC NA² NA² Ech， Vht， HdrED， Fpo	［60］［61］［59］［58］
M. mazei	G. metallireducens	Ethanol	NA²	［59］
Type Ⅱ Methanosarcina
M. acetivorans	G. metallireducens	Ethanol	Fpo， MmcA， Rnf， HdrED	［49］
M. horonobensis	G. metallireducens	Ethanol	NA²	［62］
Methanothrix
Mx. harundinacea	G. metallireducens Geobacter hydrogenophilus Rhodoferax ferrireducens	Ethanol， propanol， butanol Ethanol Glucose	HdrED NA² NA²	［57，63］［59］［59］
Mx. thermoacetophila	G. metallireducens	Ethanol	MspA， Sqp， Fpo， HdrED， HdrABC	［36］
Mx. soehngenii	G. metallireducens	Ethanol	NA²	［59］

产甲烷古菌 Methanogen	电子供体细菌 Electro-donating bacteria	电子供体 Electron donor	产甲烷古菌DIET关键蛋白 Key protein DIET of methanogenic archaeon	参考文献 Reference
Type Ⅰ Methanosarcina
M. barkeri	Geobacter metallireducens Geobacter grbiciae Rhodoferax ferrireducens Rhodopseudomonas palustris¹	Ethanol Ethanol Glucose Light， thiosulfate	Fpo， HdrABC NA² NA² Ech， Vht， HdrED， Fpo	［60］［61］［59］［58］
M. mazei	G. metallireducens	Ethanol	NA²	［59］
Type Ⅱ Methanosarcina
M. acetivorans	G. metallireducens	Ethanol	Fpo， MmcA， Rnf， HdrED	［49］
M. horonobensis	G. metallireducens	Ethanol	NA²	［62］
Methanothrix
Mx. harundinacea	G. metallireducens Geobacter hydrogenophilus Rhodoferax ferrireducens	Ethanol， propanol， butanol Ethanol Glucose	HdrED NA² NA²	［57，63］［59］［59］
Mx. thermoacetophila	G. metallireducens	Ethanol	MspA， Sqp， Fpo， HdrED， HdrABC	［36］
Mx. soehngenii	G. metallireducens	Ethanol	NA²	［59］