Food, Environment, and Other Topics in Biotechnology
Microbiol. Biotechnol. Lett. 2013; 41(1): 105-111
https://doi.org/10.4014/kjmb.1210.10006
Byung-Kwon Jung 1, Yo-Hwan Kim 1 and Sang-Dal Kim 1*
Department of Applied Microbiology and Biotechnology, School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea
Biofilm formation of multifunctional plant growth promoting rhizobacterium (PGPR), Pseudomonas fluorescens 2112 is necessary for P. fluorescens 2112 to have a positive impact on the rhizosphere of red-pepper. This study investigated whether signal molecules of the quorum sensing AHLs are produced in order to confirm biofilm formative ability. Through the use of Petri dish bioassays a blue circle formed evidence of AHLs. It was confirmed that P. fluorescens 2112 produced six-carbon-chain-long AHLs by TLC bioassay. The bacterial density of P. fluorescens 2112 on the top and bottom of pepper plant roots was estimated as 3 × 105 and 8 × 103 CFU/g root, respectively. P. fluorescens 2112 exist more with high-density of 3.5 × 106 CFU/g soil at a depth of 1 cm but at a low-density of 1.1 × 10 CFU/g soil at a depth of 5 cm, from the surface of rhizosphere soil. In addition, biofilm formation of P. fluorescens 2112 on the epidermises and the tips of the red-pepper roots were confirmed visually by SEM. Thus, the production of AHLs by P. fluorescens 2112 brings about quorum sensing signaling and the formation of biofilm on the roots which has a positive effect on economically important crops such as red-pepper by additionally producing a variety of antifungal substances and auxin.
Keywords: Quorum sensing, biofilm, PGPR, biological control, P. fluorescens 2112
Youngseok Ham, Han-Saem Park, Minjun Kim, and Tae-Jong Kim
Microbiol. Biotechnol. Lett. 2023; 51(1): 32-36 https://doi.org/10.48022/mbl.2209.09008Rujikan Nasanit, Sopin Jaibangyang, Tikamporn Onwibunsiri, and Pannida Khunnamwong
Microbiol. Biotechnol. Lett. 2022; 50(2): 202-210 https://doi.org/10.48022/mbl.2202.02004Poonam Kanojiya, Rajashri Banerji, and Sunil D. Saroj*
Microbiol. Biotechnol. Lett. 2022; 50(1): 1-14 https://doi.org/10.48022/mbl.2111.11012