Baer D, Gudmestad N C
Department of Plant Pathology, North Dakota State University, Fargo 58105, USA.
Can J Microbiol. 1995 Oct;41(10):877-88. doi: 10.1139/m95-121.
The activity of four Clavibacter michiganensis subsp. sepedonicus strains against various cellulose substrates was investigated. Sixty-seven Clavibacter michiganensis subsp. sepedonicus strains grew well on media amended with carboxymethylcellulose, 64 strains produced zones of hydrolysis. Endoglucanase activity was optimal at 37 degrees C and pH 6.0 against carboxymethylcellulose incorporated in plate assays. Zymogram and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the presence of a protein band corresponding to the cellulolytic activity in the molecular weight (MW) range of approximately 28,000. Protein bands in the same range were detected in five Clavibacter michiganensis subsp. sepedonicus strains. Studies on crude enzyme extracts of Clavibacter michiganensis subsp. sepedonicus strain N-1-1 revealed that p-nitrophenyl beta-D-cellobioside (pNPC) was hydrolyzed, with optimal activity at 37 degrees C and pH 7.0.
研究了四株密执安棒杆菌亚种环腐亚种对各种纤维素底物的活性。六十七株密执安棒杆菌亚种环腐亚种菌株在添加羧甲基纤维素的培养基上生长良好，64株产生了水解圈。在平板试验中，内切葡聚糖酶对羧甲基纤维素的活性在37℃和pH 6.0时最佳。酶谱和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳显示存在一条分子量（MW）约为28,000的与纤维素分解活性相对应的蛋白带。在五株密执安棒杆菌亚种环腐亚种菌株中检测到相同范围内的蛋白带。对密执安棒杆菌亚种环腐亚种菌株N-1-1的粗酶提取物的研究表明，对硝基苯基β-D-纤维二糖苷（pNPC）被水解，在37℃和pH 7.0时活性最佳。
