Based on genomic annotation information, this study aimed to explore the β-1,3-/α-1,3-glucan synthetic pathway of Rhizobium pusense. It focused on the action mechanism and potential catalytic efficiency of β-D-fructofuranosidase, the key enzyme in the first step of this synthetic pathway. High-throughput bioinformatic statistical and comparative analysis was conducted by targeting and mining data of β-D-fructofuranosidase from other microbial sources. The results indicated that the sequence and structure of β-D-fructofuranosidase from Rhizobium pusense showed a high degree of similarity and conservation. It was clarified that the key sites Tyr196 and Asp257 in its active site played a crucial role in catalyzing the substrate. Through high - throughput targeted mining of the database, it was found that among the microorganisms with potential β-D-fructofuranosidase expression, there were 6007 bacterial sources and 746 fungal sources. Among them, the β-D-fructofuranosidase of the representative bacterial strain Francisella tularensis OHARA and the fungal strain Fusarium fujikuroi IMI 58289 had relatively high potential catalytic efficiencies, which were 10.73 and 27.40 L·mol−1·s−1 respectively. Further analysis suggested that differences in the size of the active cavity space and the bottleneck radius of β-D-fructofuranosidase from different sources were one of the reasons for the differences in their catalytic efficiencies. This study provides an important basis for a profound understanding of the synthesis mechanism of β-1,3-/α-1,3-glucan in Rhizobium pusense. It also lays the foundation for the development and utilization of other microbial resources for the efficient fermentation production of β-1,3-/α-1,3-glucan, and is of great significance for promoting the development of related fields.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |