Uranium(VI) interactions with Pseudomonas sp. PS-0-L, V4-5-SB and T5-6-I
Year of publication
2023
Authors
Kasko, Jenna Janina; Li, Xiaodong; Müller, Katharina; Ge, Janling; Vettese, Gianni Francesco; Law, Gareth; Siitari-Kauppi, Marja; Huittinen, Nina; Raff, Johannes; Bomberg, Malin; Herzig, Merja
Abstract
<p>Pseudomonas sp. are indigenous inhabitants of ombrotrophic bogs which can survive in acidic, nutrient-poor environments with wide temperature fluctuations. Their interactions with contaminant radionuclides can influence radionuclide biogeochemistry in boreal environment. Here, uranium (U(VI)) bioassociation by Pseudomonas sp. PS-0-L, V4-5-SB and T5-6-I isolated from a boreal bog was studied by a combination of batch contact experiments, spectroscopy and microscopy. All strains removed U from the solution and the U bioassociation efficiency was affected by the nutrient source, incubation temperature, time and pH. Highest U bioassociation occurred in the strains PS-0-L (0.199 mg U/g<sub>BDW</sub>) and V4-5-SB (0.223 mg U/g<sub>BDW</sub>). Based on in-situ attenuated total reflection Fourier transformation infrared spectroscopy (ATR FT-IR) analyses, the most likely functional groups responsible for U binding were the cell surface carboxyl groups. In addition, transmission electron microscopy with energy dispersive X-ray spectroscopy (TEM/EDX) showed dense intra-cellular round- and needle-like U accumulations in the cytoplasm and near to the inner cell membrane. The presence of U with phosphorus was indicated in elemental mapping. Modelled data showed ≡ S<sup>O</sup>OH<sup>x−1</sup> and ≡ S<sup>O</sup>CO<sub>2</sub>H<sup>x−1</sup> as the dominant surface sites, contributing to the negative cell surface charge. The U removal efficiency depended on the U(VI) speciation under different pH conditions. At pH 5, the main species reacting with bacterial cell surfaces was UO<sub>2</sub><sup>2+</sup>, while at pH 9 UO<sub>2</sub>(OH)<sub>2</sub> and UO<sub>2</sub>(OH)<sub>3</sub><sup>-</sup> dominated the reactions. Further, U bioassociation increased with increasing aqueous U(VI) concentrations. Our data suggests U bioassociation on 1) outer cell membrane/cell wall associated carboxyl groups (e.g., proteins), and 2) intracellular phosphate groups (e.g., phospholipids).</p>
Show moreOrganizations and authors
University of Helsinki
Law Gareth
Vettese Gianni Francesco
Kasko Jenna Janina
Siitari-Kauppi Marja
Herzig Merja
Li Xiaodong
Publication type
Publication format
Article
Parent publication type
Journal
Article type
Original article
Audience
ScientificPeer-reviewed
Peer-ReviewedMINEDU's publication type classification code
A1 Journal article (refereed), original researchPublication channel information
Journal
Parent publication name
Volume
159
Article number
105829
ISSN
Publication forum
Publication forum level
1
Open access
Open access in the publisher’s service
Yes
Open access of publication channel
Partially open publication channel
License of the publisher’s version
CC BY
Self-archived
Yes
License of the self-archived publication
CC BY
Other information
Fields of science
Chemical sciences; Geosciences; Plant biology, microbiology, virology; Environmental engineering
Keywords
[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Internationality of the publisher
International
Language
English
International co-publication
Yes
Co-publication with a company
No
DOI
10.1016/j.apgeochem.2023.105829
The publication is included in the Ministry of Education and Culture’s Publication data collection
Yes