부산대학교 도서관

Several bacterial strains of the Pseudomonas genus provide plant growth stimulation, plant protection against pests or bioremediation. Among these bacteria, P. fluorescens Pf29 Arp reduces the severity of take-all, a disease caused by the pathogenic fungus Gaeumannomyces graminis var. tritici ( Ggt) on wheat roots. In this study, we obtained a draft genome of Pf29 Arp and subsequent comparative genomic analyses have revealed that this bacterial strain is closely related to strains of the ' P. brassicacearum-like' subgroup including P. brassicacearum ssp. brassicacearum NFM421 and P. fluorescens F113. Despite an overall chromosomal organization similar to these strains, a number of features including antibiotic synthesis gene clusters from secondary metabolism are not found in the Pf29 Arp genome. But Pf29 Arp possesses different protein secretion systems including type III ( T3 SS) and type VI ( T6 SS) secretion systems. Pf29 Arp is the first Pseudomonas sp. strain described with four T6 SS clusters (cluster I, II, III and IV). In addition, some protein-coding genes involved in the assembly of these secretion systems are basally expressed during Pf29 Arp colonization of healthy wheat roots and display different expression patterns on necrotized roots caused by Ggt. These data suggest a role of T3 SS and T6 SS in the Pf29 Arp adaptation to different root environments. [ABSTRACT FROM AUTHOR]