• Parasites, Hosts and Diseases
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• 제52권2호
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• pp.131-135
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• 2014

Acanthamoeba cysts are resistant to unfavorable physiological conditions and various disinfectants. Acanthamoeba cysts have 2 walls containing various sugar moieties, and in particular, one third of the inner wall is composed of cellulose. In this study, it has been shown that down-regulation of cellulose synthase by small interfering RNA (siRNA) significantly inhibits the formation of mature Acanthamoeba castellanii cysts. Calcofluor white staining and transmission electron microscopy revealed that siRNA transfected amoeba failed to form an inner wall during encystation and thus are likely to be more vulnerable. In addition, the expression of xylose isomerase, which is involved in cyst wall formation, was not altered in cellulose synthase down-regulated amoeba, indicating that cellulose synthase is a crucial factor for inner wall formation by Acanthamoeba during encystation.

• Asian-Australasian Journal of Animal Sciences
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• 제25권6호
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• pp.800-805
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• 2012

Rice straw is an important roughage resource for ruminants in many rice-producing countries. In this study, a rice brittle mutant (BM, mutation in OsCesA4, encoding cellulose synthase) and its wild type (WT) were employed to investigate the effects of a cellulose synthase gene mutation on rice straw morphological fractions, chemical composition, stem histological structure and in situ digestibility. The morphological fractions investigation showed that BM had a higher leaf sheath proportion (43.70% vs 38.21%, p<0.01) and a lower leaf blade proportion (25.21% vs 32.14%, p<0.01) than WT. Chemical composition analysis showed that BM rice straw was significantly (p<0.01) higher in CP (crude protein), hemicellulose and acid insoluble ash (AIA) contents, but lower in dry matter (DM), acid detergent fiber (ADFom) and cellulose contents when compared to WT. No significant difference (p>0.05) was detected in neutral detergent fiber (NDFom) and ADL contents for both strains. Histological structure observation indicated that BM stems had fewer sclerenchyma cells and a thinner sclerenchyma cell wall than WT. The results of in situ digestion showed that BM had higher DM, NDFom, cellulose and hemicellulose disappearance at 24 or 48 h of incubation (p<0.05). The effective digestibility of BM rice straw DM and NDFom was greater than that of WT (31.4% vs 26.7% for DM, 29.1% vs 24.3% for NDFom, p<0.05), but the rate of digestion of the slowly digested fraction of BM rice straw DM and NDF was decreased. These results indicated that the mutation in the cellulose synthase gene could improve the nutritive value of rice straw for ruminants.

• Genes and Genomics
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• 제40권11호
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• pp.1237-1248
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• 2018

Introduction Cellulose microfibril is a major cell wall polymer that plays an important role in the growth and development of plants. The gene cellulose synthase A (CesA), encoding cellulose synthases, is involved in the synthesis of cellulose microfibrils. However, the regulatory mechanism of CesA gene expression is not well understood, especially during the early developmental stages. Objective To identify factor(s) that regulate the expression of CesA genes and ultimately control seedling growth and development. Methods The presence of cis-elements in the promoter region of the eight CesA genes identified in flax (Linum usitatissimum L. 'Nike') seedlings was verified, and three kinds of ethylene-responsive cis-elements were identified in the promoters. Therefore, the effect of ethylene on the expression of four selected CesA genes classified into Clades 1 and 6 after treatment with $10^{-4}$ and $10^{-3}M$ 1-aminocyclopropane-1-carboxylic acid (ACC) was examined in the hypocotyl of 4-6-day-old flax seedlings. Results ACC-induced ethylene either up- or down-regulated the expression of the CesA genes depending on the clade to which these genes belonged, age of seedlings, part of the hypocotyl, and concentration of ACC. Conclusion Ethylene might be one of the factors regulating the expression of CesA genes in flax seedlings.

• Bulletin of the Korean Chemical Society
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• 제18권6호
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• pp.648-653
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• 1997

Acetolactate synthase was purified from Escherichia coli MF2000/pTATX containing Arabidopsis thaliana acetolactate synthase gene. Purification steps included DEAE cellulose ion exchange column chromatography, phenyl sepharose hydrophobic column chromatography, hydroxylapatite affinity column chromatography, and Mono-Q HPLC. Molecular weight was estimated to be ∼65 KDa and purification fold was 109 times. The enzyme showed a pH optimum of 7 and the $K_M$ value was 5.9 mM. The purified enzyme was not inhibited by any of the end products, valine, leucine, and isoleucine.

• Parasites, Hosts and Diseases
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• 제50권4호
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• pp.361-364
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• 2012

The mature cyst of Acanthamoeba is highly resistant to various antibiotics and therapeutic agents. Cyst wall of Acanthamoeba are composed of cellulose, acid-resistant proteins, lipids, and unidentified materials. Because cellulose is one of the primary components of the inner cyst wall, cellulose synthesis is essential to the process of cyst formation in Acanthamoeba. In this study, we hypothesized the key and short-step process in synthesis of cellulose from glycogen in encysting Acanthamoeba castellanii, and confirmed it by comparing the expression pattern of enzymes involving glycogenolysis and cellulose synthesis. The genes of 3 enzymes, glycogen phosphorylase, UDP-glucose pyrophosphorylase, and cellulose synthase, which are involved in the cellulose synthesis, were expressed high at the 1st and 2nd day of encystation. However, the phosphoglucomutase that facilitates the interconversion of glucose 1-phosphate and glucose 6-phosphate expressed low during encystation. This report identified the short-cut pathway of cellulose synthesis required for construction of the cyst wall during the encystation process in Acanthamoeba. This study provides important information to understand cyst wall formation in encysting Acanthamoeba.

• The Plant Pathology Journal
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• 제39권5호
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• pp.466-485
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• 2023

Crop productivity can be obstructed by various biotic and abiotic stresses and thus these stresses are a threat to universal food security. The information on the use of viruses providing efficacy to plants facing growth challenges owing to stress is lacking. The role of induction of pathogen-related genes by microbes is also colossal in drought-endurance acquisition. Studies put forward the importance of viruses as sustainable means for defending plants against dual stress. A fundamental part of research focuses on a positive interplay between viruses and plants. Notably, the tomato yellow leaf curl virus (TYLCV) and tomato chlorosis virus (ToCV) possess the capacity to safeguard tomato host plants against severe drought conditions. This study aims to explore the combined effects of TYLCV, ToCV, and drought stress on two tomato cultivars, Money Maker (MK, UK) and Shalala (SH, Azerbaijan). The expression of pathogen-related four cellulose synthase gene families (CesA/Csl) which have been implicated in drought and virus resistance based on gene expression analysis, was assessed using the quantitative real-time polymerase chain reaction method. The molecular tests revealed significant upregulation of Ces-A2, Csl-D3,2, and Csl-D3,1 genes in TYLCV and ToCV-infected tomato plants. CesA/Csl genes, responsible for biosynthesis within the MK and SH tomato cultivars, play a role in defending against TYLCV and ToCV. Additionally, physiological parameters such as "relative water content," "specific leaf weight," "leaf area," and "dry biomass" were measured in dual-stressed tomatoes. Using these features, it might be possible to cultivate TYLCV-resistant plants during seasons characterized by water scarcity.

• 약학회지
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• 제43권1호
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• pp.68-76
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• 1999

Phenoxazinone synthase catalyzes the oxidative condensation of two molecules of substituted o-aminophenol to the phenoxazinone chromophore of actinomycin. Mutant strain, Streptomyces sp. V-8-M-1 producing higher phenoxazinone synthase, was obtained from Streptomyces sp. V-8 by treatment of N-methyl-N'-nitro-N-nitrosoguanidine. The phenoxazinone synthase was purified from extract of mutant strain of Streptomyces sp. V-8-M-l by successive steps of streptomycin sulfate, ammonium sulfate precipitation. DEAE-cellulose and Sephadex G-200 column chromatography. Molecular weight of the enzyme was 360,000 daltons. The enzyme was composed of octamer of a single subunit of 45,000 daltons. The Km value and Vmax value for 3-HAA were $14.9{\;}{\mu}M$ and 9.5 mg/U, respectively. The optimal pH and temperature for the enzyme activity were 9.0 and $25~30^{\circ}C$, respectively. Treatment of the enzyme with group specific reagents, phenylglyoxal, p-hydroxymercury-benzoate, Nbromosuccinimide, 5.5'-dithiobis-nitrobenzoic acid and ethylmaleimide resulted in loss of enzyme activity, which shows arginine and cysteine residues are at or near the active site.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 추계학술대회
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• pp.215-215
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• 2017

• Weed & Turfgrass Science
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• 제3권3호
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• pp.165-173
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• 2014

국내에 등록된 제초제의 효율적 사용을 위해서 제초제저항성관리위원회에서 제시한 제초제 작용기작별 분류를 기초로 23그룹으로 분류하였다. 세부그룹으로는 acetyl CoA carboxylase 억제제, acetolactate synthase 억제제, photosystem과 억제제, protoporphyrinogen oxidase 억제제, carotenoid biosynthesis 억제제, enolpyruvyl shikimate-3-phosphate synthase 억제제, glutamine synthetase 억제제, dihydropteroate synthetase 억제제, 세포분열 저해제(mitosis inhibitors), cellulose 생합성억제제, oxidative phosphorylation uncouplers, 지방산 및 지질생합성 억제제, synthetic auxins, auxin transport 억제제, potential nucleic acid Inhibitors 혹은 non-descript mode of action으로 나누었다. 이와 같은 그룹화 기준을 토대로 국내 등록되어 사용중인 논 제초제 성분들을 그룹화 하였다. 따라서, 이러한 약제 작용기작 관련 정보를 농약사용자에게 제공함으로써 특정약제의 연용과 중복사용을 방지하여 국내에서 제초제 저항성잡초 발생 문제를 줄일 수 있을 것으로 기대된다.

• 원예과학기술지
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• 제28권6호
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• pp.1039-1050
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• 2010

당근은 서양뿐만 아니라 중국 및 한국과 같은 아시아 전역에서 요리로 많이 이용되는 유용한 작물 중 하나이다. 그러나 당근 종자 표면에는 모(毛)가 존재하고 이 종모는 발아율을 증가시키기 위해 제거해야 한다. 더욱이 종모 처리는 시간과 인력 및 자본의 소비와 같은 추가적인 손실을 동반하였다. 이러한 문제점을 방지하기 위해 단모종자를 이용하여 모형성과 관련된 유전자의 연구가 필요하다. 당근 종모의 발달은 2차 세포벽의 합성단계 동안 cellulose의 합성 과정과 연관되어 있음을 바탕으로, EST profiling을 통해 종모와 관련된 유전자를 탐색하고자 하였다. 당근 종모 형성에 관련된 유전자 발현을 조사하기 위해, 성숙 초기 단계의 단모종자 659-1개체와 유모종자 677-14개체를 이용하여 cDNA library를 구축하였다. 단모종자 659-1개체와 유모종자 677-14개체에서 확보된 EST 염기서열의 NCBI database BLASTX 분석을 통한 EST profiling 결과, 172개와 224개의 unigene은 이미 알려진 단백질 염기서열과 상동성을 보였으며 나머지 233개와 192개의 unigene은 확인되지 않는 유전자들이었다. EST는 추정되는 기능에 따라 16개의 category로 그룹화되었다. 전체 EST 중 29개의 unigene이 2차 세포벽 합성 단계 동안 cellulose의 합성 pathway상의 종모 형성을 조절하는 유전자로 추정되며, 실제로 종모 발달과 관련된 14개의 unigene이 유모종자 계통에서만 발견되었다.