Isolation, characterization and colonization of 1-aminocyclopropane-1-carboxylate deaminase-producing bacteria XG32 and DP24.
Two 1-aminocyclopropane-1-carboxylate deaminase-producing bacterial strains (DP24 and XG32) were isolated from surface-sterilized tomato roots and rizhospere soil. The strains were identified as Pseudomonas fluorescens biovar. IV (XG2) and Erwinia herbicola (DP24) by physiological and biochemical tests, and 16S rRNA gene analysis. Both strains showed positive plant growth-promoting activity when inoculated into cucumber (Cucumis sativus), tomato (Lycopersicon esculentum), pepper (Capsicum annuum) and rapeseed (Brassica napus L.). Colonization ability and behavior of these two strains were determined by treating mutant strains with rifampicin and fluorescence in situ hybridization (FISH) assay with rRNA targeted probes, respectively. Both strains were endophytic colonizers of pepper plants. The behavior of the two strains was not identical. Strain XG32 only colonized the root and reached the max level of 27.7 × 10(7) c.f.u./g (fresh weight), after 12 days postinoculation, while strain DP24 was able to colonize the roots, stems and leaves. The max level was reached at 40.87 × 10(7) c.f.u./g (fresh weight) in the roots, 17 × 10(7) c.f.u./g in the stems after 7 days postinoculation and 44.84 × 10(7) c.f.u./g in the leaves after 12 days postinoculation.
Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China.
Mei-Xia
MX
Wang
Jia
J
Liu
Shuang-Lin
SL
Chen
Shu-Zhen
SZ
Yan
D058491:Bacterial Load; D015373:Bacterial Typing Techniques; D029688:Brassica napus / Q000254:growth & development; D002212:Capsicum / Q000254:growth & development; D019755:Carbon-Carbon Lyases / Q000096:biosynthesis* / Q000235:genetics*; D016000:Cluster Analysis; D018553:Cucumis sativus / Q000254:growth & development; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D060026:Endophytes / Q000145:classification / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D004885:Erwinia / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification*; D018551:Solanum lycopersicum / Q000254:growth & development / Q000382:microbiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D018517:Plant Roots / Q000382:microbiology; D011551:Pseudomonas fluorescens / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D058441:Rhizosphere; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; C033634:1-aminocyclopropane-1-carboxylate deaminase; D019755:Carbon-Carbon Lyases