Publications by authors named "Anne-Catherine Ahn"

Haloalkaliphilic chemolithoautotrophic sulfur-oxidizing bacteria belonging to the genus are highly abundant in microbial communities found in soda lakes and dominant in full-scale bioreactors removing sulfide from industrial waste gases. Despite certain soda lakes being remote and unaffected by anthropogenic activities, haloalkaliphilic microorganisms, including strains, possess various antibiotic resistance genes. In this study, we investigated the impact of the antibiotic ampicillin on a co-culture of two species ARh2 and AL2, both experimentally and through analysis of antibiotic resistance.

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Food supplements are gaining popularity worldwide. However, harmful natural compounds can contaminate these products. In the case of algae-based products, the presence of toxin-producing cyanobacteria may cause health risks.

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The Synechococcales is a large cyanobacterial order comprising both unicellular and filamentous forms, with parietal thylakoid arrangement. Previously, this order has been the subject of taxonomic revisions with new families being erected. During studies of the phototrophic communities on the limestone walls of the Old Cathedral of Coimbra (UNESCO monument), a coccoid Aphanocapsa-like cyanobacterium was isolated.

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The continuous increase in sequenced genomes in public repositories makes the choice of interesting bacterial strains for future sequencing projects ever more complicated, as it is difficult to estimate the redundancy between these strains and the already available genomes. Therefore, we developed the Nextflow workflow "ORPER", for "ORganism PlacER", containerized in Singularity, which allows the determination the phylogenetic position of a collection of organisms in the genomic landscape. ORPER constrains the phylogenetic placement of SSU (16S) rRNA sequences in a multilocus reference tree based on ribosomal protein genes extracted from public genomes.

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The genus comprises sulfur-oxidizing bacteria thriving in soda lakes at high pH and salinity. Depending on the geographical location and the season, these lakes can strongly vary in temperature. To obtain a comprehensive understanding of the molecular and physiological adaptations to low temperature, we compared the responses of two strains to low (10°C) and high (30°C) temperatures.

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The genus includes haloalkaliphilic chemolithoautotrophic sulfur-oxidizing bacteria isolated from various soda lakes worldwide. Some of these lakes possess in addition to their extreme haloalkaline environment also other harsh conditions, to which needs to adapt. An example is arsenic in soda lakes in eastern California, which is found there in concentrations up to 3000 μM.

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Thioalkalivibrio is a genus of obligate chemolithoautotrophic haloalkaliphilic sulfur-oxidizing bacteria. Their habitat are soda lakes which are dual extreme environments with a pH range from 9.5 to 11 and salt concentrations up to saturation.

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