A BolA-like morphogene from the alga Chlamydomonas reinhardtii changes morphology and induces biofilm formation in Escherichia coli.

Escherichia coli BolA protein is a stress-inducible morphogene, regulates transcription, forms biofilms and interacts with monothiol glutaredoxins. Its presence has been documented in plants but its role remains enigmatic. This study attempts to functionally dissect the role of a BolA-domain-containing protein in the alga Chlamydomonas reinhardtii. Of the five C. reinhardtii bolA-like genes annotated for the presence of BolA-domain, the open reading frame with the highest similarity to algal systems was cloned and the protein over-expressed in E. coli. This over-expression did not affect E. coli growth but induced biofilm formation and changed its morphology, indicating functional conservancy. This is the first compelling evidence depicting the role of a plant BolA-like protein in morphogenetic pathway and biofilm formation. The implications of the phenotypic consequences of this heterologous expression are discussed.