title: The class IId bacteriocin thuricin-17 increases plant growth.
abstract: The mechanisms by which many plant growth promoting rhizobacteria (PGPR) affect plants are unknown. We recently isolated a rhizosphere bacterium (Bacillus thuringiensis NEB17), that promotes soybean growth and screened the liquid growth medium in which it grew for plant growth stimulating materials. We have also shown that it produces a bacteriocin (named by us as thuricin-17 and a member of the recently described class IId bacteriocins). Here we show that application of this bacteriocin to leaves (spray) or roots (drench) directly stimulates the growth of both a C(3) dicot (soybean) and a C(4) monocot (corn). This growth stimulation is similar in nature to that previously seen when plants are treated with Nod factors. Strain NEB17 contains three copies of the gene for thuricin 17 that code for identical amino acid sequences. These two lines of evidence suggest that the dual functions of these proteins may have constrained their evolution. This is the first report of direct plant growth enhancement by a bacteriocin.
authors.affiliation: Department of Oriental Medicine Materials, Dongshin University, 252 Daeho-dong, Naju, Jeonnam, 520-714, South Korea.
authors.forename: Kyung Dong
authors.initials: KD
authors.lastname: Lee
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Gray
authors.forename: Fazli
authors.initials: F
authors.lastname: Mabood
authors.forename: Woo-Jin
authors.initials: WJ
authors.lastname: Jung
authors.forename: Trevor
authors.initials: T
authors.lastname: Charles
authors.forename: Scott R D
authors.initials: SR
authors.lastname: Clark
authors.forename: Anh
authors.initials: A
authors.lastname: Ly
authors.forename: Alfred
authors.initials: A
authors.lastname: Souleimanov
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Zhou
authors.forename: Donald Lawrence
authors.initials: DL
authors.lastname: Smith
mesh_terms: D000595:Amino Acid Sequence; D001413:Bacillus thuringiensis / Q000235:genetics / Q000378:metabolism; D001430:Bacteriocins / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010788:Photosynthesis / Q000187:drug effects; D063245:Plant Development; D018515:Plant Leaves / Q000187:drug effects* / Q000254:growth & development; D018517:Plant Roots / Q000187:drug effects* / Q000254:growth & development; D010944:Plants / Q000187:drug effects*; D053204:Root Nodules, Plant / Q000187:drug effects / Q000254:growth & development; D013025:Glycine max / Q000187:drug effects / Q000254:growth & development; D003313:Zea mays / Q000187:drug effects / Q000254:growth & development
chemical_list: D001430:Bacteriocins; C059740:thuricin