發(fā)布時(shí)間：2018-04-03 08:33

  本文選題：鏈霉菌702　切入點(diǎn)：農(nóng)抗702　出處：《江西農(nóng)業(yè)大學(xué)》2013年博士論文

【摘要】：鏈霉菌702是江西農(nóng)業(yè)大學(xué)應(yīng)用微生物實(shí)驗(yàn)室從土壤中分離篩選到的具有獨(dú)立知識(shí)產(chǎn)權(quán)的一株鏈霉菌,其所產(chǎn)抗真菌組分農(nóng)抗702經(jīng)結(jié)構(gòu)鑒定為多烯大環(huán)內(nèi)酯類新結(jié)構(gòu)化合物。本論文主要以水稻紋枯病菌為供試病原菌,從細(xì)胞、亞細(xì)胞、生理生化、分子生物學(xué)等方面研究了農(nóng)抗702的抑菌機(jī)理及防病促生機(jī)制,主要研究結(jié)果如下：農(nóng)抗702為淡黃色粉末狀物質(zhì),熔點(diǎn)170-173.5℃,旋光度為[α]D23.7=+4.3425.(c =1.09 in MeOH),紫外光譜表明在318 nm,303 nm,290nm處有三個(gè)典型吸收峰,符合多烯類抗生素圖譜特征；紅外光譜表明其含有C=O、C=C、C-O、OH和CH2。農(nóng)抗702對(duì)熱較穩(wěn)定,溫度超過60℃活性開始下降；在強(qiáng)酸強(qiáng)堿條件下活性不穩(wěn)定,pH 5-6時(shí)活性穩(wěn)定。研究農(nóng)抗702對(duì)病菌菌絲生長(zhǎng)、菌核形成和萌發(fā)、孢子萌發(fā)的抑制作用,借助電鏡觀察其對(duì)菌絲超顯微形態(tài)和結(jié)構(gòu)的影響。結(jié)果表明,農(nóng)抗702對(duì)病菌菌絲生長(zhǎng)抑制作用明顯,處理菌絲干癟和皺縮,細(xì)胞膜輪廓不清、破損,細(xì)胞器嚴(yán)重?fù)p傷,空泡化。農(nóng)抗702明顯抑制病菌菌核的形成、萌發(fā)和孢子的萌發(fā)。通過農(nóng)抗702作用后的水稻紋枯病菌相對(duì)電導(dǎo)率增加72.2%,蛋白質(zhì)、核酸、Mg2+、K+離子等胞內(nèi)物質(zhì)均發(fā)生了不同程度的滲漏；麥角甾醇含量降低了92.0%,細(xì)胞膜的結(jié)構(gòu)不完整；清除脂質(zhì)過氧化物、自由基的能力下降。隨著農(nóng)抗702濃度的提高,病菌的侵染因子羧甲基纖維素酶、多聚半乳糖醛酸酶、果膠甲基半乳糖醛酸酶的活性均有不同程度下降。農(nóng)抗702處理水稻葉片后,明顯提高水稻抗紋枯病作用。農(nóng)抗702處理水稻秧苗,稻苗體內(nèi)的過氧化物酶,多酚氧化酶、苯丙氨酸解氨酶、過氧化氫酶等防御酶酶活性較高,對(duì)超氧化物歧化酶無顯著的影響。農(nóng)抗702處理水稻葉片后,葉片中的p-1,3葡聚糖酶活顯著提高,上調(diào)的蛋白質(zhì)點(diǎn)數(shù)較多,蛋白質(zhì)點(diǎn)表達(dá)豐度差異顯著。低濃度農(nóng)抗702促進(jìn)水稻種子萌發(fā)、胚根和芽的生長(zhǎng),根系活力提高,但含糖量下降。種子中的淀粉酶活性、蛋白質(zhì)含量隨農(nóng)抗702濃度的升高先升后降。施加鏈霉菌702菌劑后土壤細(xì)菌和霉菌數(shù)量均有所減少,放線菌數(shù)量增加,降低了硝化細(xì)菌和亞硝化細(xì)菌的菌數(shù),提高了好氣性纖維素分解菌菌數(shù),而土壤微生物不同生理類群的變化,加速了土壤養(yǎng)分循環(huán),增強(qiáng)了水稻的養(yǎng)分吸收,從而促進(jìn)水稻生長(zhǎng)。綜上所述,結(jié)合多烯大環(huán)內(nèi)酯類抗生素對(duì)真菌的作用機(jī)理,初步推斷農(nóng)抗702對(duì)病原真菌的抑菌機(jī)理是：農(nóng)抗702穿過細(xì)胞壁,與真菌細(xì)胞膜上的麥角甾醇相互結(jié)合形成麥角甾醇—抗生素復(fù)合物,增加菌體細(xì)胞膜的滲透性,進(jìn)而使酶活性降低,供能不足,抑制菌體呼吸代謝、能量代謝,最終導(dǎo)致病原真菌的細(xì)胞膜破損,細(xì)胞器嚴(yán)重?fù)p傷,生長(zhǎng)發(fā)育受到抑制,菌絲形態(tài)嚴(yán)重變形,直到死亡。另外,農(nóng)抗702能夠誘導(dǎo)水稻產(chǎn)生抗性酶,促進(jìn)種子的萌發(fā)。土壤配施鏈霉菌702提高了秧苗素質(zhì),促進(jìn)有益微生物的生長(zhǎng),抑制有害微生物的生長(zhǎng)。
[Abstract]:The 702 is Streptomyces isolated and screened with independent intellectual property rights of a strain from the soil of Jiangxi Agricultural University applied microbiology laboratory, the production of antifungal components of agricultural antibiotic 702 by structure identified as new compounds of polyene macrolide. This thesis mainly with Rhizoctonia solani as tested pathogens from the cells. Subcellular, physiological and biochemical, molecular biology and other aspects of the antibacterial mechanism of agricultural antibiotic 702 and preventing diseases and promoting growth mechanism, the main results are as follows: agricultural antibiotic 702 is light yellow powder like material, the melting point of 170-173.5 Deg. C, rotation [alpha (C =1.09]D23.7 =+4.3425. in MeOH), UV Vis spectra showed that at 318 nm. 303 nm 290nm, there are three typical absorption peaks, with polyene antibiotic spectrum; infrared spectra showed that it contains C=O, C=C, C-O, OH and CH2. Nongkang 702 stable for heat, the temperature above 60 DEG C activity began to decline in the strong acid; Under the condition of alkali activity is not stable, stable activity at pH 5-6. The research of agricultural growth of 702 anti mycelium, sclerotium formation and germination, inhibition of spore germination, electron microscope observation of the effect of micro morphology and structure of mycelia with. The results showed that the agricultural antibiotic 702 on mycelial growth inhibition and treatment of dry mycelium and cell membrane shrinkage, unclear contour, damaged organelles, serious injury, vacuolization. Formation of agricultural antibiotic 702 significantly inhibited the germination of Sclerotinia sclerotiorum, germination and spore. The agricultural antibiotic 702 after rhizoctoniasolani relative conductivity increased by 72.2%, protein, nucleic acid, Mg2+, K+ ions are intracellular substances leaking in different degrees; ergosterol content was reduced by 92%, the cell membrane structure is not complete; eliminating lipid peroxide, decreased ability of free radicals. With the increase of the concentration of agricultural antibiotic 702, bacteria infection factor Suo Jiaji Cellulase, polygalacturonase, pectin methyl galacturonate activity of all enzymes decreased in different degrees. The agricultural antibiotic 702 rice leaves after treatment, significantly improve the effect of rice sheath blight. The agricultural antibiotic 702 processing of rice seedling in rice seedlings, peroxidase, polyphenol oxidase, phenylalanine ammonia lyase, peroxidase and other defense enzymes high activity, no significant effect on superoxide dismutase. Nongkang 702 rice leaves after treatment, significantly improve the living p-1,3 glucanase in leaves, up-regulated protein spots more protein spots expressed significant difference. The low concentration of agricultural antibiotic 702 promote seed germination, radicle and shoot growth, root vigor improve, but sugar content decreased. The seeds of amylase activity, protein content increased with concentration of agricultural antibiotic 702 and then decreased. The number of soil bacteria and fungi were less applied Streptomyces 702 agent Less, the number of actinomycetes increased, reducing the number of bacteria nitrifying bacteria and denitrifying bacteria, improve aerobic cellulose decomposing bacteria number and soil microbial physiological groups change, accelerated soil nutrient cycling, enhance rice nutrient absorption, so as to promote the growth of rice. In summary, combined with the mechanism of polyene macrolide antibiotics on fungi, antibacterial mechanism preliminarily concluded the agricultural antibiotic 702 against pathogenic fungi is: agricultural antibiotic 702 through the cell wall, ergosterol and fungal cell membrane on ergosterol: antibiotic combine to form complexes, the increase of permeability of cell membrane, the enzyme activity decreased, energy supply shortage suppression bacterial respiratory metabolism, energy metabolism, resulting in damaged cell membrane of pathogenic fungi, organelles serious damage, growth inhibited the mycelial morphology severely deformed, until death. In addition, the agricultural antibiotic 702 can It is enough to induce rice to produce resistant enzymes and promote seed germination. Soil mixed Streptomyces 702 improves seedling quality, promotes beneficial microorganism growth and inhibits harmful microorganism growth.

【學(xué)位授予單位】：江西農(nóng)業(yè)大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2013
【分類號(hào)】：S435.11;S476
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本文編號(hào)：1704427