title: Growth of non-phototrophic microorganisms using solar energy through mineral photocatalysis.
abstract: Phototrophy and chemotrophy are two dominant modes of microbial metabolism. To date, non-phototrophic microorganisms have been excluded from the solar light-centered phototrophic metabolism. Here we report a pathway that demonstrates a role of light in non-phototrophic microbial activity. In lab simulations, visible light-excited photoelectrons from metal oxide, metal sulfide, and iron oxide stimulated the growth of chemoautotrophic and heterotrophic bacteria. The measured bacterial growth was dependent on light wavelength and intensity, and the growth pattern matched the light absorption spectra of the minerals. The photon-to-biomass conversion efficiency was in the range of 0.13-1.90‰. Similar observations were obtained in a natural soil sample containing both bacteria and semiconducting minerals. Results from this study provide evidence for a newly identified, but possibly long-existing pathway, in which the metabolisms and growth of non-phototrophic bacteria can be stimulated by solar light through photocatalysis of semiconducting minerals.
authors.affiliation: School of Earth and Space Sciences, Peking University, Beijing 100871, PR China.
authors.forename: Anhuai
authors.initials: A
authors.lastname: Lu
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Song
authors.initials: S
authors.lastname: Jin
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.forename: Xiao-Lei
authors.initials: XL
authors.lastname: Wu
authors.forename: Cuiping
authors.initials: C
authors.lastname: Zeng
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Hongrui
authors.initials: H
authors.lastname: Ding
authors.forename: Ruixia
authors.initials: R
authors.lastname: Hao
authors.forename: Ming
authors.initials: M
authors.lastname: Lv
authors.forename: Changqiu
authors.initials: C
authors.lastname: Wang
authors.forename: Yueqin
authors.initials: Y
authors.lastname: Tang
authors.forename: Hailiang
authors.initials: H
authors.lastname: Dong
mesh_terms: D042763:Acidithiobacillus / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects*; D042481:Alcaligenes faecalis / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects*; D001419:Bacteria / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects*; D001674:Bioelectric Energy Sources; D018533:Biomass; D008903:Minerals / Q000378:metabolism*; D052817:Phototrophic Processes; D012993:Solar Energy; D013472:Sunlight
chemical_list: D008903:Minerals