Characterization of a new transcription factor of the MerR family of Bizionia argentinensis

SIEIRA RODRIGO; PELLIZZA LEONARDO; ARÁN MARTÍN; ZORREGUIETA ÁNGELES

Santa Fe

Congreso; LIV SAB ANNUAL MEETING; 2018

SAIB

The marine genera belonging to the Flavobacteriaceae family are largely responsible for the remineralization of organic matter in the oceans and have a great environmental importance in aquatic ecosystems. However, there is still scarce information about their biological cycles and the molecular mechanisms that regulate them. In this scenario, the bacterium Bizioniaargentinensis, isolated in the National Antarctic Territory, constitutes an interesting model for the study of these marine bacteria since it has suitable characteristics for its management in the laboratory and its genome was sequenced. In this context, from a structural genomic study of B. argentinensis a new transcription factor belonging to the superfamily of the transcription factors MerR, named BA40, has been identified and characterized. Our preliminary studies showed that the protein level of BA40 is increased after exposing the bacteria to a medium lacking of nutrients, acting as a shock protein related to stress by oligotrophy. In order to elucidate a consensus DNA sequence to which BA40 was specifically bound, a high affinity selection method was used from random DNA sequences (SELEX). Using this technique, we were able to select a consensus sequence of 8 bp for which BA40 showed 21 times more affinity than a random sequence of the same length. Finally, we optimized molecular biology tools to generate mutants of B. argentinensis lacking the MerR gene in order to complement our results and identify the genetics targets of the transcription factor using ChIP-seq