Tungsten is Required for Lab Maintenance of Aigarchaeota Group 4
Aigarchaeota, a major group of microorganisms that are related to the ancestors of Eukaryotes, is found in geothermal and hydrothermal systems worldwide and consists of 9 genus-level groups. One of them, Aigarchaeota Group 4 (AigG4), was previously found to be abundant in corn stover incubations in Great Boiling Spring (GBS). This incubation sample was introduced into culture media containing corn stover or other substrates under a variety of conditions. Initially, AigG4 was only observed in culture media containing GBS water. AigG4 reconstructed genomes from environmental and laboratory samples contained multiple genes coding for hypothesized tungsten-utilizing enzymes, and ~1 µM tungsten was previously detected in GBS spring water, leading to the hypothesis that tungsten may be a necessary nutrient for AigG4. To test this, cultures containing AigG4 were introduced into an entirely artificial culture medium with corn stover in the absence or presence of 0.1 µM or 2 µM sodium tungstate. After two transfers in these media, AigG4 abundance in artificial medium with added tungstate was 2.8±1.0 x 10^6 16S rRNA gene copies/mL as determined by qPCR, similar to values in spring water medium positive controls with or without added tungsten (4.3±2.5 x 10^6 16S rRNA gene copies/mL), but AigG4 was below the level of detection (10^4 16S rRNA gene copies/mL) without added tungsten. Furthermore, expression of several of the AigG4 tungsten-utilizing enzymes were detected in the laboratory cultures using reverse transcriptase PCR. These results strongly suggest that tungsten is required for laboratory cultivation of AigG4.
Dimapilis, Joshua Robert
"Tungsten is Required for Lab Maintenance of Aigarchaeota Group 4,"
OSR Journal of Student Research: Vol. 5
, Article 257.
Available at: https://scholarworks.lib.csusb.edu/osr/vol5/iss1/257