AUTHOR=van der Kolk Nienke , Wagner Alexander , Wagner Michaela , Waßmer Bianca , Siebers Bettina , Albers Sonja-Verena 

TITLE=Identification of XylR, the Activator of Arabinose/Xylose Inducible Regulon in Sulfolobus acidocaldarius and Its Application for Homologous Protein Expression

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.01066

DOI=10.3389/fmicb.2020.01066

ISSN=1664-302X

ABSTRACT=<p>The thermophilic archaeon <italic>Sulfolobus acidocaldarius</italic> can use different carbon sources for growth, including the pentoses D-xylose and L-arabinose. In this study, we identified the activator XylR (<italic>saci_2116</italic>) responsible for the transcriptional regulation of the pentose transporter and pentose metabolizing genes in <italic>S. acidocaldarius</italic>. A <italic>xylR</italic> deletion mutant showed growth retardation on D-xylose/L-arabinose containing media and the lack of transcription of the respective ABC transporter. In contrast to so far used promoters for expression in <italic>S. acidocaldarius</italic>, the xylR responsive promoters have a very low background activity. Finally, two XylR dependent promoters next to the long-established maltose inducible promotor were used to construct a high-throughput expression vector system for <italic>S. acidocaldarius</italic> to efficiently clone and express proteins in <italic>S. acidocaldarius</italic>.</p>