The tellurite-reducing bacterium Alteromonas macleodii from a culture of the toxic dinoflagellate Prorocentrum foraminosum

Irina A Beleneva; Kseniya V Efimova; Marina G Eliseikina; Vasilii I Svetashev; Tatiana Yu Orlova

doi:10.1016/j.heliyon.2019.e02435

The tellurite-reducing bacterium Alteromonas macleodii from a culture of the toxic dinoflagellate Prorocentrum foraminosum

Heliyon. 2019 Sep 25;5(9):e02435. doi: 10.1016/j.heliyon.2019.e02435. eCollection 2019 Sep.

Authors

Irina A Beleneva¹, Kseniya V Efimova¹, Marina G Eliseikina^{1

2}, Vasilii I Svetashev¹, Tatiana Yu Orlova¹

Affiliations

¹ A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, ul. Palchevskogo 17, Vladivostok, 690041, Russia.
² Far Eastern Federal University, ul. Sukhanova 8, Vladivostok, 690950, Russia.

Abstract

The Alteromonas macleodii strain 2328 was isolated from a clonal culture of the toxic dinoflagellate Prorocentrum foraminosum. The strain exhibits a resistance to high K₂TeO₃ concentrations (2500 μg/mL). A study of the growth dynamics of the strain exposed to K₂TeO₃ has shown a longer lag phase and a reduced stationary phase compared to those during cultivation with no toxicant. The fatty acids profile is dominated by 16:1 (n-7), 16:0, 17:1, 15:0, 18:1 (n-7), and 17:0. The 2328 strain belongs to the Gammaproteobacteria and is related to the genus Alteromonas with 99-100% sequence similarity to some intra-genome allele variants (paralogues) of 16S rRNA from A. macleodii. A phylogenetic reconstruction (ML and NJ), based on HyHK amino acid sequences, has revealed that the analyzed 2328 strain forms a common cluster with A. macleodii strains. In the presented work, the ability of A. macleodii to reduce potassium tellurite to elemental tellurium has been recorded for the first time. Bacteria reduce potassium tellurite to Te (0), nanoparticles of which become distributed diffusely and in the form of electron-dense globules in cytoplasm. Large polymorphous metalloid crystals are formed in the extracellular space. Such feature of the A. macleodii strain 2328 makes it quite attractive for biotechnological application as an organism concentrating the rare metalloid.

Keywords: Alteromonas macleodii; Biotechnology; Fatty acid profile; Genetics; Microbiology; Phenotypic properties; Phylogenetic analysis; Resistance to potassium tellurite; Toxicology; Transmission electron microscopy.