雷公根叶斑病菌SJTU59纤维素酶液的性质研究及纤维素酶基因保守区域的分析  

Characterization of Cellulase Solution Produced by Leptosphaerulina chartarum SJTU59 and Analysis of Conserved Regions of Cellulase Genes

作　　者：吴琼[1] 王猛[1] 李雅乾[1] 高士刚[1] 余传金[1] 孙佳楠[1] 张泰龙 陈捷[1] 

机构地区：[1]上海交通大学农业与生物学院农业部都市农业(南方)重点开放实验室,上海200240

出　　处：《中国生物工程杂志》2014年第3期61-67,共7页China Biotechnology

基　　金：国家"863"计划(2011AA10A205);国家玉米产业体系技术专项(CRAS-02)资助项目

摘　　要：将雷公根叶斑病菌SJTU59(Leptosphaerulina chartarum SJTU59)于玉米秸秆粉为唯一碳源的培养液中诱导培养,通过DNS(3,5-二硝基水杨酸)法检测,首次发现其可以产生纤维素酶。该纤维素酶液最佳反应温度为50℃,最佳反应pH为4.8,对低温,酸碱及部分金属离子具有一定的耐受能力。在50℃,pH 4.8条件下,其最大酶活力为6.383±0.196 U/ml。利用纤维素酶基因简并引物,通过PCR技术扩增得到了2个新的纤维素酶基因的保守区域,即glu-l1(1 512 bp)和glu-l2(429 bp)。通过氨基酸序列比对及系统进化分析发现,glu-l1编码的氨基酸序列GLU-L1与Thermoascus aurantiacus var.levisporus来源的β-1,4-葡聚糖酶(ABX79553)有62%的同源性,属于第3水解家族;glu-l2编码的氨基酸序列GLU-L2与Aspergillus fumigatus Af293来源的内切-β-1,3(4)-葡聚糖酶(XP_755769)有49%的同源性,属于第16水解家族。Leptosphaerulina chartarum SJTU59 was firstly detected to produce cellulase solution in corn stalk powder via DNS （3, 5-Dinitrosalicylic acid） method. Under the optimal reaction temperature （50℃） and the optimal reaction pH （4.8）, the enzyme activity of the cellulase solution was up to 6. 383 ± 0. 196 U/ml. The enzyme solution was relatively stable over a range of pH （pH 4.0 to pH 6.0） and temperature （20℃ to 60℃ ） while showing resistance to some metal ions tested. Two sets of degenerate primers were used for PCR amplification of the conserved regions of novel cellulase genes from L. chartarum SJTU59, named glu-ll （ 1 512 bp） and glu-12 （429 bp）. Via the homology analysis of amino acid sequence and phylogenetic analysis, GLU-L1 which has 62% homology with β-1,4-glucanases （ABX79553） from Thermoascus aurantiacus var. levisporus were inferred that a conserved region of cellulase of the glycoside hydrolase （GH） family 3, while GLU-L2 which has 49% homology with β-1, 3 （4）-glucanases （XP_755769） from Aspergillus fumigatus Af293 were inferred that a conserved region of cellulase of the glycoside hydrolase （GH） family 16.

关 键 词：雷公根叶斑病菌SJTU59 纤维素酶 保守区域 

分 类 号：Q814[生物学—生物工程]