title: Effect of carbonic anhydrase on silicate weathering and carbonate formation at present day CO₂ concentrations compared to primordial values.
abstract: It is widely recognized that carbonic anhydrase (CA) participates in silicate weathering and carbonate formation. Nevertheless, it is still not known if the magnitude of the effect produced by CA on surface rock evolution changes or not. In this work, CA gene expression from Bacillus mucilaginosus and the effects of recombination protein on wollastonite dissolution and carbonate formation under different conditions are explored. Real-time fluorescent quantitative PCR was used to explore the correlation between CA gene expression and sufficiency or deficiency in calcium and CO₂ concentration. The results show that the expression of CA genes is negatively correlated with both CO₂ concentration and ease of obtaining soluble calcium. A pure form of the protein of interest (CA) is obtained by cloning, heterologous expression, and purification. The results from tests of the recombination protein on wollastonite dissolution and carbonate formation at different levels of CO₂ concentration show that the magnitudes of the effects of CA and CO₂ concentration are negatively correlated. These results suggest that the effects of microbial CA in relation to silicate weathering and carbonate formation may have increased importance at the modern atmospheric CO₂ concentration compared to 3 billion years ago.
authors.affiliation: Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
authors.forename: Leilei
authors.initials: L
authors.lastname: Xiao
authors.affiliation: Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Lian
authors.affiliation: Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
authors.forename: Jianchao
authors.initials: J
authors.lastname: Hao
authors.affiliation: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
authors.forename: Congqiang
authors.initials: C
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
authors.forename: Shijie
authors.initials: S
authors.lastname: Wang
mesh_terms: D001272:Atmosphere / Q000737:chemistry; D001407:Bacillus / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D017610:Calcium Compounds / Q000494:pharmacology; D002245:Carbon Dioxide / Q000494:pharmacology*; D002254:Carbonates / Q000737:chemistry*; D002256:Carbonic Anhydrases / Q000235:genetics / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D017640:Silicates / Q000737:chemistry* / Q000494:pharmacology; D012825:Silicon / Q000032:analysis; D012995:Solubility; D014887:Weather
chemical_list: D017610:Calcium Compounds; D002254:Carbonates; D012333:RNA, Messenger; D011994:Recombinant Proteins; D017640:Silicates; D002245:Carbon Dioxide; D002256:Carbonic Anhydrases; C031293:calcium silicate; D012825:Silicon