Abstract
To improve soil environment, utilization of terrestrial cyanobacteria attracts public attention. Nevertheless, the mechanism of desiccation tolerance of this organism has not yet been elucidated. Our previous report revealed that in desiccation tolerant cyanobacterium Abnabaena sp. PCC 7120, expression of genes for trehalose synthesis(all0168 and all0167) and hydrolysis(all0166) was up-regulated by desiccation. Trehalose is a nonreducing disaccharide, which is thought to protect cellular components against various stresses and to be involved in signal transduction as well. A small amount of trehalose was accumulated by desiccation in Abnabaena wild type. Gene disruption of all0168 resulted in a decrease in trehalose level and desiccation tolerance in comparison with wild type, whereas diruption of all0166 resulted in an increase in them. We compared the gene expression profile of wild type and all0168 disruptant by microarray analysis. We will disccuss the role of trehalose in desiccation tolerance of Abnabaena based on these results.
