An Antifungal Chitosanase from Bacillus subtilis SH21

Molecules

Linshu Jiang¹  Yuanxiang Pang¹  Yu Jia¹  Jianjun Yang¹  Junhua Jin¹  Xinyue Chen¹  Tong Li¹  Hui Liu¹  Hongxing Zhang¹  Yuanhong Xie¹  Yanling Hao² 

[1] Key Laboratory of Agricultural Product Detection and Control of Spoilage Organisms and Pesticides, Beijing Laboratory for Food Quality and Safety, Beijing Engineering Laboratory of Probiotics Key Technology Development, Beijing Engineering Technology Research Center of Food Safety Immune Rapid Detection, Food Science and Engineering College, Beijing University of Agriculture, Beijing 102206, China;Key Laboratory of Functional Dairy Science of Beijing and Chinese Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China;

关键词: Bacillus subtilis;    antifungal chitosanase;    Fusarium solani;    structure analysis;   

DOI  :  10.3390/molecules26071863

来源: DOAJ

【 摘 要 】

Bacillus subtilis SH21 was observed to produce an antifungal protein that inhibited the growth of F. solani. To purify this protein, ammonium sulfate precipitation, gel filtration chromatography, and ion-exchange chromatography were used. The purity of the purified product was 91.33% according to high-performance liquid chromatography results. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis and liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis revealed that the molecular weight of the protein is 30.72 kDa. The results of the LC–MS/MS analysis and a subsequent sequence-database search indicated that this protein was a chitosanase, and thus, we named it chitosanase SH21. Scanning and transmission electron microscopy revealed that chitosanase SH21 appeared to inhibit the growth of F. solani by causing hyphal ablation, distortion, or abnormalities, and cell-wall depression. The minimum inhibitory concentration of chitosanase SH21 against F. solani was 68 µg/mL. Subsequently, the corresponding gene was cloned and sequenced, and sequence analysis indicated an open reading frame of 831 bp. The predicted secondary structure indicated that chitosanase SH21 has a typical a-helix from the glycoside hydrolase (GH) 46 family. The tertiary structure shared 40% similarity with that of Streptomyces sp. N174. This study provides a theoretical basis for a topical cream against fungal infections in agriculture and a selection marker on fungi.

【 授权许可】

Unknown