Complete genome sequence of the nitrogen-fixing bacterium Azospirillum humicireducens type strain SgZ-5(T).

The Azospirillum humicireducens strain SgZ-5(T), belonging to the Order Rhodospirillales and the Family Rhodospirillaceae, was isolated from a microbial fuel cell inoculated with paddy soil. A previous work has shown that strain SgZ-5(T) was able to fix atmospheric nitrogen involved in plant growth promotion. Here we present the complete genome of A. humicireducens SgZ-5(T), which consists of a circular chromosome and six plasmids with the total genome size of 6,834,379 bp and the average GC content of 67.55%. Genome annotations predicted 5969 protein coding and 85 RNA genes including 14 rRNA and 67 tRNA genes. By genomic analysis, we identified a complete set of genes that is potentially involved in nitrogen fixation and its regulation. This genome also harbors numerous genes that are likely responsible for phytohormones production. We anticipate that the A. humicireducens SgZ-5(T) genome will contribute insights into plant growth promoting properties of Azospirillum strains.