• Research in Plant Disease
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• v.7 no.3
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• pp.145-149
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• 2001

A pathogenic bacterium was isolated from galls on Wistaria floibunda at Jinryang of Kyungsan, Kyungbuk, Korea in May, 2000. This bacterium was cultured and tested for pathogenicity on the host. Also its morphological and physiological characteristics were examined. Inoculation with the bacterium isolated from the gall caused the same symptoms as those under natural conditions. On the basis of bacteriological characteristics and pathogenecity on the host plant of the organism, the causal bacterium was identified as Pantoea agglomerans pv. milletiae. This is the first report of this bacterium to occur on W. floribunda plant in Korea. Therefore we proposed to name the disease as "bacterial gall of Wistaria floribunda" by P. agglomerans pv. milletiae.milletiae.

• Journal of Environmental Science International
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• v.30 no.5
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• pp.369-378
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• 2021

In this study, we investigated the effects of indole on biofilm formation inhibition in Pantoea agglomerans (P. agglomerans). In the biofilm growth assay, indole inhibited biofilm formation across all the growth time. Depending on biofilm growth stage, indole exhibited biofilm inhibition and anti-bacterial effects on planktonic cells. Through the analysis of the proportion rate between biofilm and Colony Forming Units (CFU) and inhibition rate of indole, we confirmed that depending on the biofilm stage of P. agglomerans, indole treatment timing was more important than the treatment duration. By comparing gene expression rates through rt-qPCR P.agglomerans affected by indole was found to significantly change quorum sensing (pagI/R) and indole transportation (bssS) gene expressions. Throughout all, indole exhibited both antimicrobial and anti-biofilm effects on P. agglomerans. In addition, we confirmed the anti-biofilm effects of indole on mature biofilm. In conclusion, indole as a signal molecule, can exhibit anti-biofilm effects through bacterial quorum sensing inhibition and indole affects. Therefore, indole can regulate biofilm bacteria especially gram-negative opportunistic pathogens.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.36-40
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• 2004

It is now widely accepted that immobilized microbial cells can overcome some of the problems associated with microbial survival stability, efficacy, storage, transportation and ease of application in agricultural environments. Pantoea agglomerans, a phosphate solubilizing bacterium, was immobilized in alginate, agar and gelatin carriers. All the three immobilfized carriers with bacterial cells of P. agglomerans were compared for solubilization of tricalcium phosphate in pure liquid cultures. While alginate beads were tested for phosphate solubilization on alternate days up to five days, agar beads and gelatin cubes were subjected for one time phosphate solubilization analysis after seven days. Both alginate and agar immobilized cells of P. agglomerans exhibited higher efficiency in increasing the solubilizaliun of tricalcium phosphate than gelatin immobilized cells. The culture filtrate of alginate bead inoculation treatment registered a rapid increase in soluble phosphate concentration upon incubation. A corresponding decrease in the pH of the medium was also observed in all the treatments.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.414-417
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• 2001

This research was compared the amount of phosphate solublized by Pantoea agglomerans which can solublize the insoluble phosphate salt hydroxyapatite with the phosphate produced by being treated with various acids. When P. agglomerans grows in the BY medium containing potassium dihydrogenphosphate of phosphate source without hydroxyapatite, it consumed 361mg/L phosphate, during 72hours cultivation. When 4% hydroxapatite was treated with 0.01N citric acid and oxalic aicd, the amount of solublized phosphate was 702mg/L and 537mg/L more than that by P.agglomerans. The maximum amount of solublized phosphate by P. agglomerans was 465mg/L after 48 hours cultivation.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.4
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• pp.188-193
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• 2005

Pantoea agglomerans immobilized in alginate solubilized four different rock phosphates efficiently under in vitro conditions. The solubilization pattern differed according to the rock phosphate source, where maximum solubilization of Morocco and Tunisia rock phosphates (215.6 and $186.1mg\;P\;L^{-1}$) on 6 days, Israel rock phosphate ($60.98mg\;P\;L^{-1}$) and tricalcium phosphate ($132.3mg\;P\;L^{-1}$) on 10 days and China rock phosphate ($48.8mg\;P\;L^{-1}$) on 12 days after inoculation was observed. The shelf life of the immobilized bacteria immobilized beads stored in two different temperatures was studied for six months. Beads stored at both room temperature as well as cold storage ($4^{\circ}C$) were found equally good in supporting the bacterial population as well as phosphate solubilizing activity. P. agglomerans immobilized in alginate might be exploited for large scale biosolubilization of rock phosphates intended for fertilizer use.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.4
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• pp.201-205
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• 2002

The growth conditions of Pantoea aggicmerans, a phosphate solubilizing organism, were studied In our laboratory to determine the optimal conditions. Pantoea aggionerans showed the highest growth rate at 30$\^{C}$, pH 7.0 and 2 vvm, after 50 h cultivation. A certain relationship between pH and phosphate concentration was evident when the glucose concentration in the me dium was changed. Increasing glucose concentration increased the pH buffer action of the broth. At glucose concentrations higher than the optimum concentration of 0.2 M, the cell growth was retarded. P. agglomerans consumed glucose as a substrate to produce organic acids which caused the pH decrease in the culture medium. The phosphate concentration in the medium was increased by the presence of the organic acids, which solubilized insoluble phosphates such as hydroxyapa-tite.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.364-367
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• 2000

토양속의 인산 가용화를 위한 Pantoea agglomerans 배양의 최적조건과 균주 고정화를 위한 안정성을 조사한 결과 $30^{\circ}C$, pH 7.0, 공기유량 2vvm에서 각각의 흡광도 값이 51시간에서1.756과 1,713, 50시간대에 1.819로써 가장 균의 성장이 활발한 것으로 나타났으며, 1% $CaCl_2$ 용액에서 172시간대에 흡광도값 2.361로 가장 안정하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.41-45
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• 2004

A phosphate solubilizig bacterium, Pantoea agglomerans, was isolated from rhizosphere soils collected from Chungbuk area. A greenhouse experiment was conducted to study the effect of combined application of rock phosphate and P. agglomerans inoculation on plant growth and phosphate accumulation of rice (Oryza sativa L.). Apart from control that received no inputs, six treatments were planned as follows; 1) seed bacterization, 2) free cell inoculation and 3) bacteria immobilized beads inoculation, individually and in combination with 1 and 2.5 g of rock phosphate per pot. The results showed that plant growth and phosphate uptake were significantly enhanced as a result of bacterial inoculation. Bacterial inoculation in the form of immobilized beads and 1 g of rock phosphate was found to affect positively the rice plant growth and phosphorus accumulation than other treatments. The available phosphate concentration of the pot mixture also found improved as a result of P. agglomerans inoculation. A positive correlation was observed between the phosphate concentration in the pot mixture and phosphate accumulation in plant.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.586-589
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• 2001

In this study, phosphate was produced through the solublization of hydroxyapatite and rock phosphate by Pantoea agglomerans, and it was examined the possibility of solublizing insoluble phosphate salt by immobilized P. agglomerans on Ca-alginate bead as support. 520mg/L of phosphate was solublized when P. agglomerans was cultured in HY meclium at $30^{\circ}C$, pH7, 100rpm, during 48hours culture. And solublized phosphate amount was 86.09mg/L when hydroxyapatite in the HY medium was exchanged to rock phosphate. In case of being used immobilized P. agglomerans. 740mg/L of phosphate was solublized in the HY medium, during 120hrs in the same condition. And 182mg/L of phosphate was solublized when rock phosphate was added instead of hydroxyapatite.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.494-501
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• 2013

Two phosphate solubilizing Pantoea strains (P. agglomerans and P. rodasii) were employed in elucidating their phosphate solubilizing potential under different carbon and nitrogen sources, pH, temperature and salt conditions. Plant growth promoting characteristics such as ACC deaminase activity, indole acetic acid (IAA), HCN, ammonia, and siderophore production of the two strains were assessed in vitro. Potential applicability of the strains as bio-inoculants was also evaluated in pot experiments conducted under green house conditions. Phosphate solubilization measured as the amount of phosphorous released into the medium was recorded as 810 and $788{\mu}g\;ml^{-1}$ respectively by P. agglomerans and P. rodasii. Glucose at the rate of 2% was found be the best carbon source, while $(NH_4)_2SO_4$ was the best nitrogen source for both strains. Despite a slight decrease in phosphate solubilization observed at higher temperature, pH and salt concentrations, both strains could withstand against a range of temperature ($30-35^{\circ}C$), pH (7-9) and the presence of NaCl (up to 5%) without much compromising the phosphate solubilization. Different plant growth promoting traits (ACC deaminase activity, IAA, HCN, ammonia, and siderophore production) of the strains and their ability to promote the growth of green gram seedlings indicate that both strains possess high potential to be used as bio-inoculants.