Study advances on the mechanism of soil microbial carbon fixation and associated influencing factors

doi:10.17521/cjpe.2023.0379

Abstract

Abstract:

Soil microorganisms are key drivers of carbon (C) cycling in terrestrial ecosystems not only by facilitating soil organic C decomposition and CO₂ emission, but sequestering atmospheric CO₂ into soil organic C through microbial C fixation. Due to the ubiquitous presence of microorganisms in soils, microbial C fixation is vital for terrestrial ecosystem C cycle globally. In this paper, we explored the mechanisms and determinants of soil microbial C fixation based on data collections and analyses to address the following the three issues: 1) the pathways and processes of autotrophic microbial C fixation in soil; 2) the pathways and processes of heterotrophic microbial C fixation in soil; and 3) the impacts of soil properties, ecosystem types, and climate change (i.e., warming and precipitation change) on microbial C fixation. Overall, the paper provides insights into the dynamics of C fixation in terrestrial ecosystems which is helpful for better understanding the uncertainty of soil C pool in the relationship to microbial C fixation, and which also lays a theoretical foundation for advancing of C cycling models under climate change.

Key words: autotrophic microbial carbon fixation, heterotrophic microbial carbon fixation, carbon fixation pathway, carbon cycle, climate change

GUO Qiang, HAN Zi-Chen, XIA Yun, YANG Liu-Ming, FAN Yue-Xin, YANG Yu-Sheng. Study advances on the mechanism of soil microbial carbon fixation and associated influencing factors[J]. Chin J Plant Ecol, 2024, 48(11): 1406-1421.

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途径 Pathway	能量来源 Energy source	微生物类群 Microbial community	环境 Environment	关键酶 Key enzyme	参考文献 Reference
卡尔文循环 Calvin-Benson-Bassham Cycle	光能 Solar	变形菌门、聚球藻属、原绿球藻属等 Proteobacteria, Synechococcus, Prochlorococcus et al.	好氧 Aerobic	核酮糖1,5-双磷酸羧化酶/加氧酶和磷酸核酮糖激酶 Rubisco and Ribulose phosphate kinase	Paul et al., 2000; Bar-Even et al., 2010
还原性乙酰辅酶A循环 Reductive Acetyl-CoA Cycle	氢气 Hydrogen	杨氏梭菌、产乙酸菌、产甲烷菌等 Clostridiumljungdahlii, Homoacetogen, Methanogenus et al.	厌氧 Anaerobic	乙酰辅酶A合成酶-CO脱氢酶 Acetyl coenzyme A synthetase and CO dehydrogenase enzyme	Ragsdale, 1997; Beulig et al., 2016
还原性三羧酸循环 Reductive Tricarboxylic Acid Cycle	光能、单质硫 Solar, sulfur	泥生绿菌、绿色硫黄细菌等 Chlorobiumlimicola, Chlorobiumthiosulfatophilumy et al.	厌氧 Anaerobic	2 -酮戊二酸合成酶和ATP -柠檬酸裂解酶 2-Ketoglutarate synthase, ATP-citrate lyase	Evans et al., 1966; Ivanovsky et al., 1980; Bar-Even et al., 2010
3-羟基丙酸循环 3-hydroxypropionate Cycle	光能 Solar	绿弯菌门等 Chloroflexaceae et al.	好氧 Aerobic	丙二酰辅酶A还原酶、丙二酰辅酶A合成酶和丙二酰辅酶A裂解酶 Malonyl-coenzyme A reductase, Malonyl- coenzyme A synthetase, Malonyl coenzyme A lyase	Strauss & Fuchs, 1993; Herter et al., 2001; Bar-Even et al., 2010
3-羟基丙酸/4-羟基丁酸循环 3-hydroxypropionate/4-hydroxybutyrate Cycle	氢气、单质硫 Hydrogen, sulfur	嗜泉古菌门、金属球菌、硫叶菌属、古球菌属等 Crenarchaeota, Metallosphaeraseduia, Sulfolobus, Archaeoglobus et al.	好氧 Aerobic	乙酰辅酶A丙酰辅酶A羧化酶、甲基丙二酰辅酶A变位酶和4 -羟基丁酰辅酶A脱水酶 Acetyl coenzyme A propionyl coenzyme A carboxylase, Methylmalonyl-coenzyme A transferase, 4-Hydroxybutyryl-coenzyme A dehydratase	Berg et al., 2007; Huber et al., 2008; Bar-Even et al., 2010
二羧酸/4-羟基丁酸循环 Dicarboxylate/4- hydroxybutyrate Cycle	氢气、单质硫 Hydrogen, sulfur	嗜泉古菌、热变形菌目、除硫球菌目等 Crenarchaeal, Thermoproteales, Desulfurococcales et al.	厌氧 Anaerobic	4-羟基丁酰基辅酶A脱水酶 4-Hydroxybutyryl coenzyme A dehydrogenase	Bar-Even et al., 2010; Berg et al., 2010b

途径 Pathway	能量来源 Energy source	微生物类群 Microbial community	环境 Environment	关键酶 Key enzyme	参考文献 Reference
卡尔文循环 Calvin-Benson-Bassham Cycle	光能 Solar	变形菌门、聚球藻属、原绿球藻属等 Proteobacteria, Synechococcus, Prochlorococcus et al.	好氧 Aerobic	核酮糖1,5-双磷酸羧化酶/加氧酶和磷酸核酮糖激酶 Rubisco and Ribulose phosphate kinase	Paul et al., 2000; Bar-Even et al., 2010
还原性乙酰辅酶A循环 Reductive Acetyl-CoA Cycle	氢气 Hydrogen	杨氏梭菌、产乙酸菌、产甲烷菌等 Clostridiumljungdahlii, Homoacetogen, Methanogenus et al.	厌氧 Anaerobic	乙酰辅酶A合成酶-CO脱氢酶 Acetyl coenzyme A synthetase and CO dehydrogenase enzyme	Ragsdale, 1997; Beulig et al., 2016
还原性三羧酸循环 Reductive Tricarboxylic Acid Cycle	光能、单质硫 Solar, sulfur	泥生绿菌、绿色硫黄细菌等 Chlorobiumlimicola, Chlorobiumthiosulfatophilumy et al.	厌氧 Anaerobic	2 -酮戊二酸合成酶和ATP -柠檬酸裂解酶 2-Ketoglutarate synthase, ATP-citrate lyase	Evans et al., 1966; Ivanovsky et al., 1980; Bar-Even et al., 2010
3-羟基丙酸循环 3-hydroxypropionate Cycle	光能 Solar	绿弯菌门等 Chloroflexaceae et al.	好氧 Aerobic	丙二酰辅酶A还原酶、丙二酰辅酶A合成酶和丙二酰辅酶A裂解酶 Malonyl-coenzyme A reductase, Malonyl- coenzyme A synthetase, Malonyl coenzyme A lyase	Strauss & Fuchs, 1993; Herter et al., 2001; Bar-Even et al., 2010
3-羟基丙酸/4-羟基丁酸循环 3-hydroxypropionate/4-hydroxybutyrate Cycle	氢气、单质硫 Hydrogen, sulfur	嗜泉古菌门、金属球菌、硫叶菌属、古球菌属等 Crenarchaeota, Metallosphaeraseduia, Sulfolobus, Archaeoglobus et al.	好氧 Aerobic	乙酰辅酶A丙酰辅酶A羧化酶、甲基丙二酰辅酶A变位酶和4 -羟基丁酰辅酶A脱水酶 Acetyl coenzyme A propionyl coenzyme A carboxylase, Methylmalonyl-coenzyme A transferase, 4-Hydroxybutyryl-coenzyme A dehydratase	Berg et al., 2007; Huber et al., 2008; Bar-Even et al., 2010
二羧酸/4-羟基丁酸循环 Dicarboxylate/4- hydroxybutyrate Cycle	氢气、单质硫 Hydrogen, sulfur	嗜泉古菌、热变形菌目、除硫球菌目等 Crenarchaeal, Thermoproteales, Desulfurococcales et al.	厌氧 Anaerobic	4-羟基丁酰基辅酶A脱水酶 4-Hydroxybutyryl coenzyme A dehydrogenase	Bar-Even et al., 2010; Berg et al., 2010b