Isolation and identification of endophytic thermophilic bacteria YYFG3 from flue-cured tobacco and its protease activity

被引：0

作者：

Sun, Huizhong ^{[1
]}

Wang, Xiaodong ^{[1
]}

Zhu, Jinfeng ^{[2
]}

Li, Guangliang ^{[2
]}

Sun, Minghui ^{[2
]}

Xu, Zhicheng ^{[3
]}

Song, Yueqin ^{[1
]}

机构：

[1] College of Agriculture, Henan University of Science and Technology, Luoyang, 471003, Henan

[2] Henan Luohe Municipal Tobacco Corporation, Luohe, 462000, Henan

[3] College of Tobacco Science, Henan Agricultural University, Zhengzhou

来源：

Acta Tabacaria Sinica | 2015年 / 21卷 / 06期

关键词：

16S rDNA; Endophytic bacteria; Isolation; Nicotiana tabacum; Protease;

D O I：

10.16472/j.chinatobacco.2015.122

中图分类号：

学科分类号：

摘要：

Thermophilic bacteria strain producing protease YYFG3 was isolated from flue-cured tobacco (Nicotiana tabacum L.) by using solid culture medium and milk agar medium. The growth temperature was in the range of 30-65℃, and the optimum growth temperature was 55℃. The tolerance of pH was in the range of 5-9, and the optimum pH was 6-7. After 32h fermentation under the condition of 55℃, 180 r/min, protease activity reached the maximum value of 35.3 U/mL. Therefore, the YYFG3 was identified as a thermophilic strain producing protease. Morphological characteristics of strain YYFG3 were observed by optical microscope and scanning electron microscope, and related biochemical properties were measured. 16S rDNA was cloned and sequenced, and its phylogenetic tree was established. YYFG3 was classified into the genus Geobacillus, and temporarily named Geobacillus sp. YYFG3. It was concluded that strain YYFG3 can be used as good material for conventional mutation breeding and genome breeding of thermophilic bacteria producing proteinase and enjoyed a good prospect for further development and application. © 2015, Acta Tabacaria Sinica Editorial Department. All right reserved.

引用

页码：121 / 126

页数：5