A novel bacteriocin, thuricin 17, produced by plant growth promoting rhizobacteria strain Bacillus thuringiensis NEB17: isolation and classification.
OBJECTIVE
The aim of this study was to identify and characterize a compound produced by the plant growth promoting bacterium, Bacillus thuringiensis non-Bradyrhizobium Endophytic Bacterium 17.


RESULTS
The bacterial peptide was analysed and purified via HPLC. Using the disk diffusion assay this peptide inhibited the growth of 16/19 B. thuringiensis strains, 4/4 Bacillus cereus strains, among others, as well as a Gram-negative strain Escherichia coli MM294 (pBS42). Both bactericidal and bacteristatic effects were observed on B. cereus ATCC 14579 and bactericidal effects were observed on B. thuringiensis ssp. thuringiensis Bt1267. The molecular weight of the peptide was estimated via SDS-PAGE and confirmed with Matrix Assisted Laser Desorption Ionization Quadrapole Time of Flight mass spectrometry; its weight is 3162 Da. The peptide is biologically active after exposure to 100 degrees C for 15 min, and within the pH range 1.00-9.25. Its activity disappeared when treated with proteinase K and protease, but not with alpha-amylase or catalase.


CONCLUSIONS
We conclude that this is the first report of a bacteriocin produced by a plant growth promoting rhizobacteria (B. thuringiensis) species and have named the bacteriocin thuricin 17.


CONCLUSIONS
Our work has characterized a bacteriocin produced by a plant growth promoting bacterium. This strain is previously reported to increase soya bean nodulation.
Department of Plant Science, McGill University-Macdonald Campus, St Anne-de-Bellevue, QC, Canada.
E J
EJ
Gray
K D
KD
Lee
A M
AM
Souleimanov
M R
MR
Di Falco
X
X
Zhou
A
A
Ly
T C
TC
Charles
B T
BT
Driscoll
D L
DL
Smith
D000900:Anti-Bacterial Agents / Q000145:classification / Q000302:isolation & purification* / Q000494:pharmacology; D001407:Bacillus / Q000187:drug effects; D001413:Bacillus thuringiensis / Q000737:chemistry* / Q000254:growth & development; D001430:Bacteriocins / Q000145:classification / Q000302:isolation & purification* / Q000494:pharmacology; D002374:Catalase / Q000378:metabolism; D002474:Cell-Free System; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D015169:Colony Count, Microbial / Q000379:methods; D003470:Culture Media; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D019286:Endopeptidase K / Q000378:metabolism; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D010447:Peptide Hydrolases / Q000378:metabolism; D010455:Peptides / Q000145:classification / Q000302:isolation & purification / Q000494:pharmacology; D000516:alpha-Amylases / Q000378:metabolism
D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D003470:Culture Media; D010455:Peptides; C059740:thuricin; D002374:Catalase; D000516:alpha-Amylases; D010447:Peptide Hydrolases; D019286:Endopeptidase K