Zhengzhou Tobacco Research Institute of CNTC, Henan Province, Zhengzhou, 450001, PR China.
Anhui Wannan Tobacco Co. Ltd, Xuancheng, An'Hui province, 242000, PR China.
BMC Microbiol. 2024 Nov 22;24(1):491. doi: 10.1186/s12866-024-03613-w.
Enterobacter ludwigii has been proven by numerous studies to be an effective plant growth promoter. Enterobacter ludwigii T977 was isolated from leaves of Nicotiana tabacum L. Yunyan 97 which showing high starch degrading ability. The optimal fermentation carbon source of strain T977 was starch, with optimal starch concentration as 2.5 g/L, and the most suitable fermentation nitrogen source for the strain T977 was ammonium acetate, with optimal concentration as 0.25 g/L. The spaying treatment of strain T977 could reduce the starch content of upper leaves from 3.77% to 1.43%, the total sugar and reducing sugar decreased slightly, the starch content of middle leaves decreased from 5.63% to 3.18%, the content of total sugar and reducing sugar increased in middle leaves, and the other chemical components were in the appropriate range. Here, we reported 4.77 MB whole genome of a starch-degrading E. ludwigii T977 that encodes 4501 proteins, 11 α-amylases in GH13 family were identified, and the amylase (GM000159) with signal peptide may play important role in degradation of starch in tobacco leaves. Our study may provide an effective microbiological mean for reducing starch content in tobacco leaves.
已有大量研究证明，阴沟肠杆菌是一种有效的植物生长促进剂。从表现出高淀粉降解能力的烟草（Nicotiana tabacum L. Yunyan 97）叶片中分离得到了阴沟肠杆菌 T977。该菌株 T977 的最佳发酵碳源是淀粉，最佳淀粉浓度为 2.5 g/L；最适合该菌株的发酵氮源是乙酸铵，最佳浓度为 0.25 g/L。T977 菌株的喷施处理可将上部叶片中的淀粉含量从 3.77%降低至 1.43%，总糖和还原糖略有下降，中部叶片中的淀粉含量从 5.63%降低至 3.18%，中部叶片中的总糖和还原糖含量增加，其他化学成分均在适宜范围内。在这里，我们报道了一株淀粉降解阴沟肠杆菌 T977 的 4.77MB 全基因组，该基因组编码 4501 种蛋白质，鉴定出 11 种 GH13 家族的α-淀粉酶，具有信号肽的淀粉酶（GM000159）可能在烟草叶片淀粉降解中发挥重要作用。我们的研究可能为降低烟草叶片中的淀粉含量提供了一种有效的微生物手段。
