Abstract
Recently, many genes involved in photoperception, signal transduction, and pilus biogenesis, which are responsible for cellular motility and phototaxis, have been identified in a unicellular motile cyanobacterium Synechocystis sp. PCC 6803. Meanwhile, a thermophilic cyanobacterium Thermosynechococcus elongatus BP-1, whose genome sequence was determined, also shows motility and phototaxis. Here, we report functional analysis of genes involved in motility and phototaxis by using T. vulcanus strain RKN which is closely related to T. elongatus. T. vulcanus forms slightly spreading colonies on agar plates under normal culture conditions. In the course of our study on glycosyltransferase, we found a certain strain of the glycosyltransferase mutants showed enhanced motility with negative phototaxis toward white light. Moreover, addition of glucanase to the agar plate significantly enhanced motility. We disrupted several genes involved in motility and phototaxis on the genetic background of the motile glycosyltransferase mutant. We will report phenotype of those disruptants.
