식물에서 인의 역할과 인산염 고갈 위기 대응 방안

신나현(Na-Hyun Shin),조래현(Lae-Hyeon Cho) (사)한국식물생명공학회 2024 JOURNAL OF PLANT BIOTECHNOLOGY Vol.51 No.2

Phosphate, an important macronutrient required for plant growth, is involved in various processes, including energy metabolism, and is also a key component of nucleic acids and phospholipids. Phosphorus fertilizers are not reusable and phosphate rock, which is the only phosphorus fertilizer resource, is limited and becoming depleted. To address this issue, phosphate transporters that can absorb phosphate from underground soil and transport it to plant aerial parts have been identified in Arabidopsis and major crops, such as rice, wheat, barley, maize, and soybean. Phosphate in the soil is primarily absorbed through diffusion via phosphate gradients between the soil and plant and transported to the shoot via the xylem. The plant uses the acquired phosphate and it accumulates in the seeds, thereby influencing plant growth for the next generation. Symbiotic phosphate acquisition via arbuscular mycorrhizal fungi and the genes or quantitative trait loci involved in increased phosphate uptake with enhanced yield have been reported. However, besides climate, soil phosphate uptake is affected by various environmental factors such as soil water content, pH, texture, temperature, and element composition. Thus, developing crops with desired traits for high phosphate uptake and phosphate-use efficiency and cultivating them in appropriate environments is essential. This review provides comprehensive information on transporters and genes or quantitative trait loci that are known to enhance phosphate acquisition and transportation. Moreover, we discuss measures to address the problem of phosphorus depletion.

Application of Immobilization Technology in Solubilization of Rock Phosphate

Buddhi Charana Walpola,Ah Young Kim,Ju Hyeon Jeon,Min-Ho Yoon 한국토양비료학회 2014 한국토양비료학회지 Vol.47 No.4

Phosphates solubilizing bacterial strains belong to Pantoea, Burkholderia and Enterobacter were isolated and employed in assessing their solubilization ability of Ca phosphate and ER phosphate (Eppawala Rock Phosphate). Among the bacterial strains used, PSB-13 (Pantoea rodasii) showed higher Ca-phosphate solubilization (1100 μg ml<SUP>-1</SUP>) as well as rock phosphate solubilization (168 μg ml<SUP>-1</SUP>). The strain was then immobilized in agar to further assess its phosphate solubilization ability. According to the results, agar encapsulated strain solubilized 0.3%, 7.31%, 20.24%, and 20.62% more Ca-phosphate and 11.53%, 15.29%, 28.48%, 36.55% (respectively in 4 cycles) more ER- phosphate than free cells. The reuse efficiency of agar entrapped bacterial cells for Ca-phosphate and ER-phosphate solubilization was greater than that by freely suspended bacterial cells. In conclusion, immobilization could enhance the phosphate solubilization capacity of the strains and thus could be used effectively in enhancing solubilization of ER phosphate.

Phosphate Solubilization and Gene Expression of Phosphate-Solubilizing Bacterium Burkholderia multivorans WS-FJ9 under Different Levels of Soluble Phosphate

( Qingwei Zeng ),( Xiaoqin Wu ),( Jiangchuan Wang ),( Xiaolei Ding ) 한국미생물 · 생명공학회 2017 Journal of microbiology and biotechnology Vol.27 No.4

Phosphate-solubilizing bacteria (PSB) have the ability to dissolve insoluble phosphate and enhance soil fertility. However, the growth and mineral phosphate solubilization of PSB could be affected by exogenous soluble phosphate and the mechanism has not been fully understood. In the present study, the growth and mineral phosphate-solubilizing characteristics of PSB strain Burkholderia multivorans WS-FJ9 were investigated at six levels of exogenous soluble phosphate (0, 0.5, 1, 5, 10, and 20 mM). The WS-FJ9 strain showed better growth at high levels of soluble phosphate. The phosphate-solubilizing activity of WS-FJ9 was reduced as the soluble phosphate concentration increased, as well as the production of pyruvic acid. Transcriptome profiling of WS-FJ9 at three levels of exogenous soluble phosphate (0, 5, and 20 mM) identified 446 differentially expressed genes, among which 44 genes were continuously up-regulated when soluble phosphate concentration was increased and 81 genes were continuously down-regulated. Some genes related to cell growth were continuously up-regulated, which would account for the better growth of WS-FJ9 at high levels of soluble phosphate. Genes involved in glucose metabolism, including glycerate kinase, 2-oxoglutarate dehydrogenase, and sugar ABC-type transporter, were continuously down-regulated, which indicates that metabolic channeling of glucose towards the phosphorylative pathway was negatively regulated by soluble phosphate. These findings represent an important first step in understanding the molecular mechanisms of soluble phosphate effects on the growth and mineral phosphate solubilization of PSB.

Application of Immobilization Technology in Solubilization of Rock Phosphate

Walpola, Buddhi Charana,Kim, Ah Young,Jeon, Ju Hyeon,Yoon, Min-Ho Korean Society of Soil Science and Fertilizer 2014 한국토양비료학회지 Vol.47 No.4

Phosphates solubilizing bacterial strains belong to Pantoea, Burkholderia and Enterobacter were isolated and employed in assessing their solubilization ability of Ca phosphate and ER phosphate (Eppawala Rock Phosphate). Among the bacterial strains used, PSB-13 (Pantoea rodasii) showed higher Ca-phosphate solubilization ($1100{\mu}g\;ml^{-1}$) as well as rock phosphate solubilization ($168{\mu}g\;ml^{-1}$). The strain was then immobilized in agar to further assess its phosphate solubilization ability. According to the results, agar encapsulated strain solubilized 0.3%, 7.31%, 20.24%, and 20.62% more Ca-phosphate and 11.53%, 15.29%, 28.48%, 36.55% (respectively in 4 cycles) more ER-phosphate than free cells. The reuse efficiency of agar entrapped bacterial cells for Ca-phosphate and ER-phosphate solubilization was greater than that by freely suspended bacterial cells. In conclusion, immobilization could enhance the phosphate solubilization capacity of the strains and thus could be used effectively in enhancing solubilization of ER phosphate.

토양에서 분리한 Aspergillus sp. PS-104 균주에 의한 난용성 인산염 분해

강선철 ( Sun Chul Kang ),신승용 ( Seung Yong Shin ) 한국환경농학회 2007 한국환경농학회지 Vol.26 No.1

Phosphate-solubilizing microorganisms were isolated from soil around Kyungnam and Kyungbook regions using potato dextrose agar-calcium phosphate medium. A fungus with the greatest phosphate-solubilizing activity was selected and identified to Aspergillus sp. PS-104, based on the morphological characteristics of conidiophore and conidia; unbranching type of conidiophore, terminally swelling of conidiophore and septate of mycelium, in malt extract agar and potato dextrose agar media. The optimum temperature and initial pH to solubilize rock phosphate in potato dextrose broth-rock phosphate medium were 30℃ and pH 7.0, respectively. In these optimum conditions, phosphate-solubilizing activities of Aspergillus sp. PS-104 against four types of insoluble phosphate, tricalcium phosphate, aluminium phosphate, hydroxyapatite and rock phosphate, were quantitatively determined. As results, the maximum phosphate-solubilizing activity was obtained with tricalcium-phosphate (1,900 ppm) while minimum activity was obtained with hydroxyapatite (320 ppm). Futhermore, phosphate-solubilizing activity of Aspergillus sp. PS-104 was found higher when treated with nitrates as compared to the ammonium salts as a nitrogen sources.

세균의 인산 항상성: 인산 수송 단백질들의 역할

박윤미,방일수,Park, Yoon-Mee,Bang, Iel-Soo 한국미생물학회 2012 미생물학회지 Vol.48 No.2

인은 인지질, 탄수화물 및 핵산 등의 생분자 합성에 필요한 원소이다. 세균은 외부환경으로부터 인산이나 인산을 포함하는 영양소를 흡수하여 인을 얻고, 세포대사에 사용되고 남은 인산은 polyphosphate 형태로 저장한다. 현재까지 알려진 다섯 개의 인산 수송 시스템 중, 인산에 특이적으로 높은 친화력을 갖는 Pst 시스템이 가장 중요한 역할을 하며, 그 발현은 세포외부 인산 농도에 반응하는 PhoB-PhoR two component 신호전달 시스템에 의해 조절된다. 반응 조절 단백질 PhoB는 인산 대사뿐 아니라 이와 관계없는 유전자들의 전사를 조절하는 것으로 알려졌으며, 따라서 PhoB의 활성이 조절되지 않으면 많은 종류의 다른 표현형이 나타난다. 본 총설은 각 인산 수송 시스템의 기능이 결여된 세균의 표현형에 대한 최근 연구 결과를 토대로 다음과 같은 내용을 기술하였다. 첫째, 세포 내부 인산의 적정 농도 유지를 위한 인산 수송 시스템들의 역할, 둘째, 인산뿐 아니라 여타 환경 신호와 관련된 수송 시스템의 다양한 표현형, 그리고 마지막으로, 수송 시스템들 간 혹은 그 조절자들 간의 표현형 중복을 분류하여 제시하였다. 이러한 내용은 결국 세균의 대사, 적응반응 및 병원성 발현에 미치는 인산 항상성의 중요성을 강조한다. Phosphorous is an essential element for the synthesis of various biomolecules including phospholipids, carbohydrates and nucleic acids. Bacterial cells can uptake it as forms of phosphate and phosphate-containing nutrients from extracellular environments, and reserve extra phosphate to polyphosphate inside the cell. Among five phosphate transport systems, Pst plays central roles in phosphate transport, and its expression is coordinated by the regulation of PhoB-PhoR two component signal transduction system in response to extracellular levels of phosphate. Genomic studies on the response regulator PhoB reveal many genes independent of phosphate metabolism. Based on recent findings on phenotypes of bacteria lacking proper function of each phosphate transport system, this review discusses roles of phosphate transporters in maintaining optimum intracellular phosphate levels, and presents diverse phenotypes of phosphate transporters related with other environmental signals as well as phosphate, then finally points out functional redundancy among phosphate transport systems or their regulators, which emphasize importance of phosphate homeostasis in governing metabolism, adaptation, and virulence of bacteria.

활성 적니를 이용한 해수중의 인 흡착 특성

김이태 ( I Tae Kim ) 한국수처리학회 2013 한국수처리학회지 Vol.21 No.5

The objective of this study was to obtain basic information about phosphate adsorption by activated red mud(ARM)in sea water. The selective adsorption of phosphate ions from artificial sea water was examined along with other commercial adsorbents(Phosphate-outⓡ(Germany, EHEIM Company), PhosBanⓡ(USA, Two-little fish Company)). According to the application of the activated red mud, the influence of pH and alkalinity were observed which is in the hands of the stability problem during the application of adsorbent was verified. Activated red mud analysis mainly Ca, Fe, Al, Si, and Mg as the complex was composed and the state mineral Hematite (Fe2O3) and Calcite (Ca(CO3)) were identified as valid for phosphate adsorption with Gibbsite (Al(OH)3), Brucite (Mg3(OH)6), Portlandite (Ca(OH)2) respectively. Activated red mud for phosphate removal in seawater was 80% (initial phosphate concentration of 1mg / L condition). It was a higher value than the commercial product (Phosphate-outTM: 68%, PhosBanTM: 71%). In seawater by activated red mud for phosphate adsorption was 0.8mgPO42?P/g(activated red mud). pH variation of the activated red mud phosphate adsorption capacity was sensitive to the pH change and the phosphate adsorption capacity at the range of pH> 4 or less was higher than in natural seawater pH range from 7.5 to 8.5 range, the relative phosphate adsorption capacity dropped significantly. Under the current conditions for the removal of phosphate in sea water of the appropriate dosage of the activated red mud 0.8 - 1.0g / L had a fair value of infusion conditions. Also, activated red mud secondary leaching of hazardous substances do not occur in water from dissolution experiments.

Influence of Different pH Conditions and Phosphate Sources on Phosphate Solubilization by Pantoea agglomerans DSM3493

Buddhi Charana Walpola,Mi-Jung Keum,Min-Ho Yoon 한국토양비료학회 2012 한국토양비료학회지 Vol.45 No.6

Pantoea agglomerans DSM3493 was isolated from green house soils collected from Chungchugnam-do province, Gongju-Gun area in South Korea and phosphate solubilization and organic acid production of the strain were assessed using three types of insoluble phosphate sources (Ca phosphate, Fe phosphate and Al phosphate) under three different pH conditions (7, 8 and 9). The highest Ca phosphate solubilization (651 μg mL^-1) was recorded at pH 7 followed by pH 8 and 9 (428 and 424 μg mL^-1 respectively). The solubilization rate was found to be 80.4, 98.1 and 88.7 μg mL^-1 (for Fe phosphate containing medium) and 9.3, 12.1 and 29.8 μg mL^-1 (for the Al phosphate containing medium) respectively at pH 7, 8 and 9. Though increasing pH of the medium caused reduction in the rate of solubilization of Ca phosphate, solubilization of Fe and Al phosphates enhanced with increasing pH. By contrast, the highest amount of organic acid was produced with Ca phosphate while the lowest was recorded with the presence of Al phosphate. Among the organic acids, gluconic acid production was found to be the highest, followed by oxalic acid and citric acid regardless the source of phosphate. Results can thus be concluded that the production of organic acids appears to play a significant role in the inorganic phosphate solubilization.

Influence of Different pH Conditions and Phosphate Sources on Phosphate Solubilization by Pantoea agglomerans DSM3493

Walpola, Buddhi Charana,Keum, Mi-Jung,Yoon, Min-Ho Korean Society of Soil Science and Fertilizer 2012 한국토양비료학회지 Vol.45 No.6

Pantoea agglomerans DSM3493 was isolated from green house soils collected from Chungchugnam-do province, Gongju-Gun area in South Korea and phosphate solubilization and organic acid production of the strain were assessed using three types of insoluble phosphate sources (Ca phosphate, Fe phosphate and Al phosphate) under three different pH conditions (7, 8 and 9). The highest Ca phosphate solubilization ($651{\mu}g\;mL^{-1}$) was recorded at pH 7 followed by pH 8 and 9 (428 and $424{\mu}g\;mL^{-1}$ respectively). The solubilization rate was found to be 80.4, 98.1 and $88.7{\mu}g\;mL^{-1}$ (for Fe phosphate containing medium) and 9.3, 12.1 and $29.8{\mu}g\;mL^{-1}$ (for the Al phosphate containing medium) respectively at pH 7, 8 and 9. Though increasing pH of the medium caused reduction in the rate of solubilization of Ca phosphate, solubilization of Fe and Al phosphates enhanced with increasing pH. By contrast, the highest amount of organic acid was produced with Ca phosphate while the lowest was recorded with the presence of Al phosphate. Among the organic acids, gluconic acid production was found to be the highest, followed by oxalic acid and citric acid regardless the source of phosphate. Results can thus be concluded that the production of organic acids appears to play a significant role in the inorganic phosphate solubilization.

HDPE/EPDM/Boron Carbide/Triphenyl Phosphate 블렌드의 상용화제 첨가에 따른 난연성 및 기계적 물성 연구

신범식(Bum Sik Shin),정승태(Seung Tae Jung),전준표(Joon Pyo Jeun),김현빈(Hyun Bin Kim),오승환(Seung Hwan Oh),강필현(Phil Hyun Kang) 한국고분자학회 2012 폴리머 Vol.36 No.5

난연제 triphenyl phosphate는 HDPE(high-density polyethylene)/EPDM(ethylene-propylene diene monomer)/boron carbide 내에서 miscibility가 좋지 못하여 고분자의 기계적 물성을 크게 저하시킨다. HDPE/EPDM/boron carbide/triphenyl phosphate 블렌드의 분산성을 향상시키기 위해서 상용화제로 PE-g-MAH(polyethylene-graft-maleic anhydride)를 사용하여 블렌딩하였다. Triphenyl phosphate 함량이 증가할수록 인장강도를 크게 저하시킴을 확인하였다. 하지만 상용화제 첨가로 인하여 기계적 물성이 향상되는 것을 확인하였다. Triphenyl phosphate의 분산성의 향상은 SEM 분석을 통해서 확인하였다. HDPE/EPDM/boron carbide/triphenyl phosphate의 내열성과 난연성을 측정하기 위해서 TGA 분석과 LOI 분석을 진행하였다. 분산성이 향상됨에 따라서 triphenyl phosphate 첨가제의 기본적인 특성인 내열성과 난연성이 향상되었으며, 그 결과로 자기 소화성인 21% 이상의 한계산소지수(LOI)를 가지는 HDPE/EPDM/boron carbide/triphenyl phosphate 블렌드를 얻을 수 있었다. It was known that triphenyl phosphate wasn`t homogeneously dispersed in HDPE/EPDM/boron carbide blends, which caused the decrease in mechanical properties. HDPE, EPDM, boron carbide, and triphenyl phosphate were blended with PE-g-MAH(polyethylene-graft-maleic anhydride) as a compatiblizer for improving the miscibility of triphenyl phosphate. Tensile strength of HDPE/EPDM/boron carbide blends decreased with increasing the contents of triphenyl phosphate for flammability. However, the mechanical properties of HDPE/EPDM/boron carbide/triphenyl phosphate blends increased by the addition of compatiblizer because triphenyl phosphate was homogeneously mixed in the blend system. The homogeneous dispersibility of triphenyl phosphate was confirmed by using scanning electron microscopy (SEM). Increased thermal stability and flammability derived from high miscibility of triphenyl phosphate were confirmed by the results of thermogravimetric analysis (TGA) and limiting oxygen index (LOI). A self-extinguishing HDPE/ EPDM/boron carbide/triphenyl phosphate blend was successfully fabricated with more than 21% LOI.