애기장대 잎에서 광음향법을 이용한 금 나노입자 추적

구연종,서정원 전남대학교 농업과학기술연구소 2017 농업생명과학연구동향 Vol.54 No.

ABSTRACT Gold nanoparticles (GNPs) are one of most widespread nanoparticles in use for biomedical applications, such as immunoassays, clinical, phototherapy of cancer cells, targeted delivery of drugs and optical bioimaging. Use of nanoparticles in plants has not yet been fully investigated however, only few methods are available for visualizing and quantifying nanoparticles to assess uptake, translocation and stability in planta. Recently, we found that GNPs can be easily detected quantitatively in leaves by laser-induced photoacoustic imaging and leaf temperature can be elevated by GNP mediated photothermal effect. Here, we detect 60 nm GNP with photoacoustic signal and find that (i) 60 nm GNP reached to the leaf tip from leaf petiole inside 4 hours, (ii) GNPs are finally localized in leaf vein, hydathode of leaf marginal part. This work demonstrates that nanoparticles can be rapidly taken up through the leaf vein and expected to be eliminated through leaf phloem or hydathode.

Characterization of a Methyl Jasmonate Specific Esterase in Arabidopsis

구연종,윤은실,서준성,김주곤,최양도 한국응용생명화학회 2013 Applied Biological Chemistry (Appl Biol Chem) Vol.56 No.1

Methyl jasmonate (MeJA)-specific methyl esterase of Arabidopsis (AtMJE) was identified and characterized. AtMJE has high substrate specificity to MeJA compared to other related substrates, methyl indole-3-acetate (MeIAA) and methyl salicylate (MeSA). Through enzyme kinetics analysis, we found AtMJE has similar level of substrate affinity to JA carboxyl methyltransferase (AtJMT). However, AtMJE has 10 times lower catalytic efficiency than AtJMT at low substrate concentrations. AtMJE gene expression was suppressed for 2 h after MeJA treatment, even though its expression recovered and was induced to maximum level within 8 h after treatment. AtMJE overexpressing plants (AtMJEox)showed enhanced MeJA methyl esterase activity demonstrating esterase activity of AtMJE in vivo. AtMJEox plants responded differentially to JA and MeJA in root growth. MeJA in the media could be a source for more JA production in AtMJEox plants,which resulted in root growth inhibition. In contrast, AtMJEox plants grown on JA containing media showed similar root growth inhibition as wild-type. These results show that AtMJE functions in altering JA/MeJA ratios in Arabidopsis and increased JA,because the conversion of MeJA to JA enhances JA responsive gene expression.

Movement of Metal Nanoparticle and GNP mediated Photothermal Impact in Arabidopsis

구연종 ( Yeonjong Koo ),자넷부라암 ( Janetbraam ) 한국환경농학회 2018 한국환경농학회 학술대회집 Vol.2018 No.-

The basic information to develop nanoparticle as a functional material is discovering nanoparticle movement in plant tissues. Two different methods were carried out to tracking nanoparticle in Arabidopsis. First, Arabidopsis was exposed to CdSe/CdZnS QDs with three different coatings, anionic, cationic, and relatively neutral, and nanoparticle movement was dramatically changed from the particle absorption into the plant root cell to the particle localization in plant leaves. T. ni caterpillars that fed on Arabidopsis exposed to QDs had reduced performance, and QD fluorescence was detected in both T. ni bodies and frass, demonstrating trophic transfer of intact QDs from plants to insects. Second, gold nanoparticle was applied to test the biological responses to photothermal effects of nanoparticles. The uptake of gold nanoparticle through Arabidopsis roots and translocation to leaves are reported through the photoacoustic signal detection. Furthermore, Arabidopsis leaves harboring GNPs and exposed to continuous laser or noncoherent light show elevated temperatures across the leaf surface and induced expression of heat-shock regulated genes. Overall, these results demonstrate that metal based nanoparticles are strong candidate as a substance carrier for manipulating plant physiology.

제초제 저항성 단백질 연구 현황과 CRISPR-Cas9 시스템을 활용한 제초제 저항성 토마토 개발 전략

김의연,박효선,구연종,양소희 전남대학교 농업과학기술연구소 2019 농업생명과학연구동향 Vol.57 No.-

The devlopment of herbicde-tolerant plants provide aconvenient farming method. The five most poular herbicdes are glyphosate, sulfonylureas/imdazolinoes, glufosinate, norflurasone and oxyfluorfen. Thes herbicdes inhibt 5-enolpyruvylshikmate-3phosphate synthase (EPS), acetohydroxyacid synthase (AHAS), glutamine synthetase (GS), Phytoen desaturase (PDS) and protporphyrinogen oxidase (PO), respectively. Inhibtion of EPS and AHAS reduces the biosynthesi of phenolic and branched amino acids, respectively, and inhibtion of GS and PDS enhances the production of reactive oxygen specis and induces plant necrosi. Inhibtion of PO decrease chlorphyl biosynthesi and inhibts plant photsynthesi. Thes herbicdes induce plant death by interacting with their target proteins therfore the devlopment of herbicde rsitant plants ibased on the discovery of mutant proteins insensitive tohes herbicdes. We rviewd the devlopment of herbicde-tolerant plants anderived target amino acids for the production of herbicde-tolerant proteins using the CRISPR/Cas9 sytem in tomatoes

농업환경에서 메탄 발생 경로와 메타노젠의 다양성

문수빈,백지현,구연종 전남대학교 농업과학기술연구소 2022 농업생명과학연구동향 Vol.60 No.-

Methane is a potent greenhouse gas that is produced naturally through various bioogical processes, includin the decomposition of organic matter. Two common sources of methane production are cow dung and paddy soil. Cow dung is a rich source of organic matter and is widely used as a fertilizer and fuel. Methane production from cow dung occurs in the rumen of cows durin the digestion process, where the bacteria present in the rumen break down the organic matter and produce methane as a by-product. The major methanogens are members of the Archaea domain, specifically the genus Methan-obrevibacter. These methanogens are known to produce methane by breaking down the complex organic matter in the cow's stomach. Paddy soil is the soil used for cultivating paddy rice, which is flooded with water during the growing season. The flooded conditions create anaerobic conditions, which promote the growth of methanogenic bacteria is the soil. These bcteria brea down the organic matter in the soil and produce methane as a by-product, which is released into the atmosphere through the rice plant roots and the soil surface. The major methanogens are also member of the Archaea domain, but they belong to a different genus called Methanosaeta. Methanosaeta are known to produce methane by metabolizing acetate, which is produced by other microorganisms in the soil. In this report, we compare the methane production of two different agricultural methane sources n terms of bacterial diversity and biochemical pathways for methane production.

고추 재배지에서 완효성 비료의 아산화질소 발생 저감 효과 검정

백지현,이평호,구연종 한국응용생명화학회 2024 Journal of Applied Biological Chemistry (J. Appl. Vol.67 No.-

Nitrous oxide is a potent greenhouse gas with a significant impact on global warming and the depletion of the stratospheric ozone layer. The primary source of nitrous oxide in agricultural soils is the excessive application of inorganic nitrogen during the crop growth stage. This gas is generated through the nitrification followed by denitrification processes facilitated by soil bacteria. We confirmed that supplying nitrogen through controlled-release fertilizer can effectively decrease the production of nitrous oxide while maintaining similar pepper growth compared to urea fertilizer treatment. The microbial community analysis revealed a reduction in nitrification-denitrification-related bacteria, which were typically increased by using urea fertilizer, when controlled-release fertilizer was employed. Additionally, the amplification of nirK and nosZ genes associated with denitrification in the soil bacterial community remained at a lower level compared to the urea fertilizer treatment group. These findings suggest that the utilization of controlled-release fertilizers effectively mitigates nitrous oxide emissions by reducing the population of denitrification-associated bacteria. The findings of this paper highlight that slow-release fertilizer not only functions as a growth promoter for peppers but also serves as an environmentally friendly option capable of suppressing nitrous oxide generation.

Heterologous expression of bacterial trehalose biosynthetic genes enhances trehalose accumulation in potato plants without adverse growth effects

심재성,서주석,서준성,김용환,구연종,최양도,정춘균 한국식물생명공학회 2019 Plant biotechnology reports Vol.13 No.4

Trehalose is a non-reducing disaccharide found in various organisms, including bacteria, fungi, invertebrates, and plants. It plays essential roles in diverse biological processes such as stress resistance, metabolism, and development in plants. Despite the important role of trehalose, it is challenging to increase trehalose levels because of its negative effects on plant growth and development. In this study, we tested several combinations of different promoters and trehalose biosynthetic genes to efficiently accumulate trehalose in potato plants. Transgenic potato plants expressing TPSP (trehalose-6-phosphate synthase/ phosphatase) fusion gene under the control of Rd29A promoter increased trehalose content in response to high salt stress and did not show significant growth retardation. Although constitutive overexpression of plastid-targeted MTSH (maltooligosyltrehalose synthase/trehalohydrolase) fusion gene driven by CaMV 35S promoter remarkably accumulated trehalose, the transgenic potato plants showed a severely stunted phenotype. By contrast, stress-inducible expression of plastid-targeted MTSH under the control of Rd29A promoter led to trehalose accumulation without growth defects in response to high salt stress. Besides, tuber-specific expression of plastid-targeted MTSH driven by GBSS (granule-bound starch synthase) promoter specifically increased trehalose level in potato tubers without stunting growth. Consequently, we suggest that heterologous expression of TPSP and MTSH fusion genes driven by stress-inducible or tuber-specific promoters can be an effective strategy for accumulating trehalose in potato plants as well as minimizing its adverse effects on potato growth.

후코이단과 후코이단 이용 박테리아의 멜론 성장 촉진 효과 검증

양소희,길예지,오희정,구연종 한국환경농학회 2020 한국환경농학회지 Vol.39 No.1

BACKGROUND: Marine algae is a productive organism that is consumed as a nutritious food. However, large amounts of unused portions of the algae are incinerated as trash or dumped in the sea, causing pollution. Recycling algae is important for saving resources and conserving the environment. In this study, the fucoidan which is a major carbohydrate of marine algae was tested as a source of fertilizer for farming. METHODS AND RESULTS: The growth rate of the melon was examined after treating fucoidan and the melon growth factors, weight and length of stem were measured. To discover the mechanism of melon growth promotion of fucoidan, bacteria that decomposed fucoidan were isolated from soil and abalone. Bacillus wiedmannii and Stenotrophomonas pavanii were isolated from terrestrial soil and Pseudomonas sp. was isolated from abalone. Among these three bacteria, Pseudomonas sp. had the highest and most specific fucoidan-decomposing activity. When Pseudomonas sp. was treated with fucoidan on melon-growing soil, the growth of melon was relatively improved compared to the treatment with fucoidan alone. CONCLUSION: We found that fucoidan, the main carbohydrate of marine algae, promoted melon growth. Fucoidan-decomposing microorganisms were isolated from terrestrial soil and marine organism, and we found that these bacteria stimulated the effect of melon growth promotion of marine algae. This is the first report that confirms the fertilizer effect of marine algae and shows the use of bacteria with marine algae. .

돈분 액비의 아산화질소 발생 저감 효과 검정

이평호 ( Pyeong Ho Lee ),백지현 ( Ji Hyeon Baek ),구연종 ( Yeonjong Koo ) 한국환경농학회 2023 한국환경농학회지 Vol.42 No.4

This study focused on nitrous oxide, a major greenhouse gas produced in agricultural settings through bacterial nitrogen oxidation in aerobic soil. Nitrogen fertilizer in farmland is identified as a primary source of nitrous oxide. The importance of reducing excess nitrogen in soil to mitigate nitrous oxide production is well-known. The study investigated the use of liquefied pig manure as an alternative to urea fertilizer in conventional agriculture. Results showed a more than two-fold reduction in nitrous oxide emissions in pepper cultivation areas with liquefied pig manure compared to that with urea fertilizer. The population of Nitrosospira, a nitrous oxide-producing bacterium, decreased by over 10% with liquefied pig manure. Additionally, nirK and nosZ, which are related to the denitrification process, significantly increased in the urea fertilizer group, whereas levels in the liquefied pig manure group resembled those with no nitrogen treatment. In conclusion, the experiment confirmed that liquefied pig manure can serve as an eco-friendly nitrogen fertilizer, significantly reducing nitrous oxide production, a major contributor to the atmospheric greenhouse effect.

Agrobacterium을 이용한 토마토 떡잎에서 CRISPR-Cas9 시스템의 임시발현 시 토마토 떡잎 발달 단계에 따른 유전자교정 효율 변화

김의연 ( Euyeon Kim ),양소희 ( So Hee Yang ),박효선 ( Hyosun Park ),구연종 ( Yeonjong Koo ) 한국환경농학회 2021 한국환경농학회지 Vol.40 No.3

BACKGROUND: Before generating transgenic plant using the CRISPR-Cas9 system, the efficiency test of sgRNAs is recommended to reduce the time and effort for plant transformation and regeneration process. The efficiency of the sgRNA can be measured through the transient expression of sgRNA and Cas9 gene in tomato cotyledon; however, we found that the calculated efficiency showed a large variation. It is necessary to increase the precision of the experiment to obtain reliable sgRNA efficiency data from transient expression. METHODS AND RESULTS: The cotyledon of 11^th, 15^th, 19^th, and 23^rd-day-old tomato (Solanum lycopersicum cv. Micro-Tom) were used for expressing CRISPR-Cas9 transiently. The agrobacterium harboring sgRNA for targeting ALS2 gene of tomato was injected through the stomata of leaf adaxial side and the genomic DNA was extracted in 5 days after injection. The target gene edition was identified by amplifying DNA fragment of target region and analyzing with Illumina sequencing method. The target gene editing efficiency was calculated by counting base deletion and insertion events from total target sequence read. CONCLUSION: The CRISPR-Cas9 editing efficiency varied with tomato cotyledon age. The highest efficiency was observed at the 19-day-old cotyledons. Both the median and mean were the highest at this stage and the sample variability was also minimized. We found that the transgene of CRISPR-Cas9 system was strongly correlated with plant leaf development and suggested the optimum cotyledon leaf age for Agrobacterium-mediated transfection in tomato.