title: The co-culture of Acidithiobacillus ferrooxidans and Acidiphilium acidophilum enhances the growth, iron oxidation, and CO2 fixation.
abstract: Although the synergetic interactions between chemolithoautotroph Acidithiobacillus ferrooxidans and heterotroph Acidiphilium acidophilum have drawn a share of attention, the influence of Aph. acidophilum on growth and metabolic functions of At. ferrooxidans is still unknown on transcriptional level. To assess this influence, a co-culture composed by At. ferrooxidans and Aph. acidophilum was successfully acclimated in this study. Depending on the growth dynamics, At. ferrooxidans in co-culture had 2 days longer exponential phase and 5 times more cell number than that in pure culture. The ferrous iron concentration in culture medium and the expression of iron oxidation-related genes revealed that the energy acquisition of At. ferrooxidans in co-culture was more efficient than that in pure culture. Besides, the analysis of CO2 fixation-related genes in At. ferrooxidans indicated that the second copy of RuBisCO-encoding genes cbbLS-2 and the positive regulator-encoding gene cbbR were up-regulated in co-culture system. All of these results verified that Aph. acidophilum could heterotrophically grow with At. ferrooxidans and promote the growth of it. By means of activating iron oxidation-related genes and the second set of cbbLS genes in At. ferrooxidans, the Aph. acidophilum facilitated the iron oxidation and CO2 fixation by At. ferrooxidans.
authors.affiliation: School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, Hunan, China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Liu
authors.forename: Huaqun
authors.initials: H
authors.lastname: Yin
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Dai
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Dai
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.forename: Huidan
authors.initials: H
authors.lastname: Jiang
authors.forename: Xueduan
authors.initials: X
authors.lastname: Liu
mesh_terms: D041801:Acidiphilium / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D042763:Acidithiobacillus / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D000222:Adaptation, Physiological; D002245:Carbon Dioxide / Q000378:metabolism*; D018920:Coculture Techniques; D003470:Culture Media; D015964:Gene Expression Regulation, Bacterial; D052836:Heterotrophic Processes; D007501:Iron / Q000378:metabolism*; D010084:Oxidation-Reduction; D012273:Ribulose-Bisphosphate Carboxylase / Q000235:genetics / Q000378:metabolism
chemical_list: D003470:Culture Media; D002245:Carbon Dioxide; D007501:Iron; D012273:Ribulose-Bisphosphate Carboxylase