本文選題：炭樣小單孢菌 + 核苷類抗生素��； 參考：《江西師范大學》2013年碩士論文

【摘要】：新抗生素產(chǎn)生菌的分離、篩選是研發(fā)新抗生素的重要途徑之一，，課題組前期研究獲得的炭樣小單孢菌所產(chǎn)抗菌單體組分經(jīng)鑒定為一新型核苷類抗生素。該抗生素具有廣譜抗菌活性，但抗菌作用特點及作用機理不清楚。本研究以該抗生素和常用抗生素活性檢測靶菌分別作為試驗材料和試驗對象，研究抗生素的體外抗菌譜、抗菌方式、抗菌強度及其作用機理，為進一步開發(fā)炭樣小單孢菌產(chǎn)抗生素成為我國具有自主知識產(chǎn)權的新型抗生素奠定堅實的理論基礎，具有重大的理論研究和實踐應用價值。研究結果如下： （1）采用瓊脂擴散法和液體稀釋法分別測定了炭樣小單孢菌所產(chǎn)核苷類抗生素抗菌譜及其最低抑菌濃度和最低殺菌強度，表明該抗生素對常見的G+和G-均具有抗菌作用，為廣譜抗生素，并且對G+和G-的最低殺菌濃度（MBC）一般是最低抑菌濃度（MIC）的8～16倍。 （2）采用顯微觀察法研究了炭樣小單孢菌所產(chǎn)核苷類抗生素處理后的G+和G-細菌形態(tài)變化，結果顯示，在最低抑菌濃度的抗生素作用下，無論是G+、G-，細胞形態(tài)都發(fā)生明顯改變，許多細胞形體變長，甚至成絲狀，還有部分細胞開始破裂，并且，細胞的個體數(shù)目明顯減少。 （3）通過比較抗生素處理前后細胞對溶菌酶的敏感性及細胞壁的含量，表明炭樣小單孢菌所產(chǎn)核苷類抗生素的作用不影響細菌細胞壁的合成，但使細胞壁變厚。 （4）通過比較抗生素作用后細胞懸浮液的電導率變化，表明抗生素對細菌細胞膜的滲透性沒有明顯的影響，說明不影響細胞膜的結構與功能。 （5）采用孔雀石綠—磷鉬雜多酸分光光度法測定了抗生素對細胞GTP酶活性的影響，表明炭樣小單孢菌所產(chǎn)抗生素可促進細胞GTP酶的活性，進而增強了GTP酶的催化作用。 （6）采用G-250考馬斯亮藍法檢測了炭樣小單孢菌所產(chǎn)抗生素作用下G+和G-細菌細胞內蛋白質含量的變化，及其對大腸埃希氏菌無細胞表達系統(tǒng)體外合成蛋白質的影響，表明炭樣小單孢菌所產(chǎn)抗生素可抑制細胞蛋白質的合成。 從上述結果可以推斷，炭樣小單孢菌所產(chǎn)抗生素通過抑制細胞蛋白質的合成而抑制細胞的分裂，進而實現(xiàn)其抑/殺菌功能。但有關該抗生素抑制蛋白質合成的具體機制還有待進一步研究。
[Abstract]:Isolation and screening of new antibiotic producing bacteria is one of the important ways to develop new antibiotics. The antibiotic has broad-spectrum antibacterial activity, but its characteristics and mechanism are not clear. In this study, the antimicrobial spectrum, antimicrobial method, antibacterial intensity and its mechanism of antibiotics were studied by using the antibiotic and the commonly used antibiotic activity detection target bacteria as the test materials and experimental objects, respectively. It lays a solid theoretical foundation for the further development of carbon-like micromonosporium antibiotics as a new type of antibiotics with independent intellectual property rights in China, and has great theoretical research and practical application value. The results are as follows: 1) the antimicrobial spectrum of nucleosides produced by Micromonosporium carboniformis and its minimum inhibitory concentration and bactericidal intensity were determined by Agar diffusion method and liquid dilution method respectively. The results showed that the antibiotic had antimicrobial effect on both G and G-, and it was a broad-spectrum antibiotic. And the minimum bactericidal concentration (MBC) of G and G- was 816 times of the minimum inhibitory concentration (MICM). The morphological changes of G and G- bacteria were studied by microscopic observation after treatment with nucleoside antibiotics produced by Micromonospora. In the presence of antibiotics with the lowest inhibitory concentration, the morphology of the cells, no matter the G G, changed significantly, many of the cells became longer, even became filamentous, and some of the cells began to break down, and, By comparing the sensitivity of cells to lysozyme and cell wall content before and after antibiotic treatment, the results showed that the effect of nucleoside antibiotics produced by Micromonosporium carboniformis did not affect the synthesis of bacterial cell wall. But the thickening of the cell wall showed that antibiotics had no obvious effect on the permeability of bacterial cell membrane by comparing the changes of the electrical conductivity of the cell suspensions after the treatment of antibiotics. The results showed that the structure and function of cell membrane were not affected. (5) the effect of antibiotics on the activity of GTP enzyme was determined by malachite green-molybdenum heteropoly acid spectrophotometry, which indicated that the antibiotics produced by Micromonosporium Carboniformis could promote the activity of GTP enzyme. Furthermore, the catalytic activity of GTP enzyme was enhanced. (6) G-250 Coomassie brilliant blue method was used to detect the changes of protein contents in G and G- bacteria cells under the action of antibiotics produced by Micromonosporium carboniformis. And its effect on the protein synthesis of Escherichia coli acellular expression system in vitro, indicating that antibiotics produced by Micromonosporium carboniformis can inhibit the synthesis of cellular protein. The antibiotics produced by Micromonosporium carboniformis inhibit cell division by inhibiting the synthesis of cell proteins and thus achieve its inhibitory / bactericidal function. However, the mechanism of inhibition of protein synthesis by this antibiotic remains to be further studied.
【學位授予單位】：江西師范大學
【學位級別】：碩士
【學位授予年份】：2013
【分類號】：S482.28

【參考文獻】

相關期刊論文 前10條

1 蔚慧;楊林華;李志民;;綠色木霉代謝產(chǎn)物對黑曲霉和荔枝炭疽抑菌機理的研究[J];安徽農(nóng)業(yè)科學;2009年31期

2 柳煥章;劉建釵;周敬霄;;微生物間拮抗的研究方法與農(nóng)業(yè)應用[J];安徽農(nóng)業(yè)科學;2011年03期

3 ;Screening antagonistic microbes for seedling blight of rice and study on antagonistic mechanisms[J];Journal of Northeast Agricultural University(English Edition);2007年02期

4 劉長庭;抗生素臨床應用、細菌耐藥機制及其新藥——“β-內酰胺類抗菌素臨床應用及研究進展”研討會紀要[J];當代醫(yī)學;2000年05期

5 胡海峰,朱寶泉,龔炳永;生物活性物質的篩選與新藥研究[J];國外醫(yī)藥(抗生素分冊);1998年06期

6 程元榮,黃威;小單孢菌產(chǎn)生的生物活性物質[J];國外醫(yī)藥(抗生素分冊);1998年06期

7 甘亞,呂丁;抗真菌藥物的作用機制[J];國外醫(yī)藥(抗生素分冊);1998年06期

8 張宏印,李電東;博萊霉素作用機制研究進展[J];國外醫(yī)藥(抗生素分冊);1999年06期

9 徐錚,曹永兵,姜遠英;麥角甾醇生物合成途徑中的抗真菌藥作用靶酶[J];國外醫(yī)藥(抗生素分冊);2001年05期

10 程振泰;莊鴻;黃喜桂;黃穎楨;林如;鄭衛(wèi);;小單孢菌產(chǎn)生的扁枝衣霉素B的研究[J];海峽藥學;2006年05期

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