Zn isotope fractionation during interaction with phototrophic biofilm
Abstract
This study addresses Zn isotopic fractionation during its sorption and excretion with a mature phototrophic biofilm using both a batch reactor and an open drip flow reactor (DFR). Short-term batch adsorption experiments demonstrated an enrichment in heavier isotopes larger than that induced by biofilm's Zn uptake, in general agreement with previous results for aquatic micro-organisms. Presumably, the adsorption of heavy isotopes was controlled by the formation of strong covalent bonds with the surface moieties rather than the kinetics of diffusion through the boundary layer to the biofilm surface. The rapid physico-chemical passive desorption was driven by the exchange of H⁺/Zn²⁺ ions with a highly negative isotopic enrichment factor (e.g. ε⁶⁶Znexcretion of − 1.4 ± 0.35‰). The Zn efflux dominated by diffusion due to the osmotic biofilm–solution gradient favored lighter isotope release (e.g. ε⁶⁶Znexcretion of − 0.40 ± 0.07‰ for wet biofilm in the DFR). The passive physico-chemical processes of Zn diffusion and H⁺/Zn²⁺ ion exchange are capable of inducing greater isotopic separation between solution and biomass compared to the active (intracellular) uptake. Regardless of the nature of aquatic microorganisms, the biomass enrichment with heavy isotopes during adsorption and uptake and preferential release of light isotopes seem to be general characteristics of aquatic biota
Related
- Characterization of NfnAB of Heliomicrobium modesticaldum, an Electron Bifurcating Enzyme Involved in Phototrophic Energy Conversion
- The interaction between NC(p7)1-55 and p6 may regulate interactions with nucleic acids during assembly through modulation of Gag folding.
- Interaction-specific early wheat responses to Zymoseptoria tritici share enhanced defense-related transcription during incompatibility
- An orphan LuxR regulator controls plant developmental reprogramming during interaction with Novosphingobium resinovorum HR1a
- Structural control over equilibrium silicon and oxygen isotopic fractionation: A first-principles density-functional theory study
BibTeX
@article{coutaud2026isotope,
title = {{Zn isotope fractionation during interaction with phototrophic biofilm}},
author = {Aude Coutaud and Merlin Méheut and Jérôme Viers and Jean-Luc Rols and Oleg Pokrovsky},
journal = {Chemical Geology},
year = {2026},
month = sep,
doi = {10.1016/j.chemgeo.2014.10.004},
url = {https://hal.science/hal-05748940v1},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Zn isotope fractionation during interaction with phototrophic biofilm
AU - Aude Coutaud
AU - Merlin Méheut
AU - Jérôme Viers
AU - Jean-Luc Rols
AU - Oleg Pokrovsky
PY - 2026
DA - 2026/09/14
JO - Chemical Geology
DO - 10.1016/j.chemgeo.2014.10.004
UR - https://hal.science/hal-05748940v1
AB - This study addresses Zn isotopic fractionation during its sorption and excretion with a mature phototrophic biofilm using both a batch reactor and an open drip flow reactor (DFR). Short-term batch adsorption experiments demonstrated an enrichment in heavier isotopes larger than that induced by biofilm's Zn uptake, in general agreement with previous results for aquatic micro-organisms. Presumably, the adsorption of heavy isotopes was controlled by the formation of strong covalent bonds with the surface moieties rather than the kinetics of diffusion through the boundary layer to the biofilm surface. The rapid physico-chemical passive desorption was driven by the exchange of H⁺/Zn²⁺ ions with a highly negative isotopic enrichment factor (e.g. ε⁶⁶Znexcretion of − 1.4 ± 0.35‰). The Zn efflux dominated by diffusion due to the osmotic biofilm–solution gradient favored lighter isotope release (e.g. ε⁶⁶Znexcretion of − 0.40 ± 0.07‰ for wet biofilm in the DFR). The passive physico-chemical processes of Zn diffusion and H⁺/Zn²⁺ ion exchange are capable of inducing greater isotopic separation between solution and biomass compared to the active (intracellular) uptake. Regardless of the nature of aquatic microorganisms, the biomass enrichment with heavy isotopes during adsorption and uptake and preferential release of light isotopes seem to be general characteristics of aquatic biota
SN - 0009-2541
ER -