摘要
通过筛选高效纤维素降解细菌用于聚羟基丁酸酯(PHB)的生产,可以降低原料成本。采用刚果红染色法从天津北大港湿地的土壤中筛选具有降解纤维素能力的菌株,比较透明圈的大小后分离获得1株纤维素降解菌株SX-5,根据菌株的形态和生理生化特征并结合分子生物学手段,鉴定菌株SX-5属于芽孢杆菌属(Bacillus sp.),其16S rDNA序列与芽孢杆菌属的同源性为99%。该菌株在pH5.5~7.5、温度25℃~41℃范围内可以利用纤维素进行生长,其最适pH 6.5,最适生长温度35℃。同时,通过比较不同碳源,发现其在玉米秸秆作为唯一碳源的培养基中具有较高的产酶活性。利用该菌株进行聚羟基丁酸酯(PHB)的合成,构建了从纤维素进行PHB合成的途径,成功获得36%的PHB产量。该研究为木质纤维素类农产品的开发和利用提供了良好的菌种资源和科学依据,同时为降低PHB的生产成本提供了新的思路和途径。
To screen highly efficient cellulose degrading bacteria,and develop a bacterial for PHB production,the raw material cost can be reduced.A cellulolytic bacterium SX-5 was screened and isolated from the soil of Tianjin Beidagang wetland by Congo red staining and the size of the transparent circle was compared.The strain SX-5 was identified as Bacillus sp.based on morphological,physiological and biochemical characteristics and 16 S rDNA sequence similarity(99%).The strain was detected at pH 5.5~7.5 and temperature 25℃~41℃within the range,cellulose can be used for growth,its optimum pH 6.5,the optimum growth temperature of 35℃.At the same time,by comparing different carbon sources,it was found in jade rice straw as the only carbon source of the medium has a higher enzyme production activity.By constructing the pathway of PHB,the SX-5 can produce 36%PHB from corn straw powder.This study provides a good strain resource and scientific basis for the development and utilization of lignocellulosic agricultural products,and provides a new idea and way to reduce the production cost of PHB.
作者
薛玮
喻恬
李祖慧
朱紫倩
任秋婷
吴弘
Xue Wei;Yu Tian;Li Zuhui;Zhu Ziqian;Ren Qiuting;Wu Hong(College of Life Science,Tianjin Normal University,Tianjin,300387)
出处
《基因组学与应用生物学》
CAS
CSCD
北大核心
2020年第9期4047-4052,共6页
Genomics and Applied Biology
基金
国家大学生创新创业训练计划项目(No.201810065003)
天津师范大学引进人才基金项目(No.5RL147)共同资助
