Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea.
Department of Environmental Engineering, Yonsei University, Wonju, 26493, Republic of Korea.
J Microbiol. 2021 May;59(5):491-499. doi: 10.1007/s12275-021-0679-6. Epub 2021 Mar 29.
Little is known about final spores components when bacteria undergo sporulation under different nutrient conditions. Different degrees of resistance and germination rates were observed in the three types of spores of Lysinibacillus boronitolerans YS11 (SD, Spores formed in Difco sporulation medium™; SC and SF, Spores formed in an agricultural byproduct medium with 10 mM CaCl and with 10 mM FeSO, respectively). Stronger UV resistance was recorded for SF with 1.8-2.3-fold greater survival than SC and SD under UV treatment. The three spore types showed similar heat resistances at 80°C, but survival rates of SC and SD were much higher (∼1,000 times) than those of SF at 90°C. However, germination capacity of SF was 20% higher than those of SD and SC on Luria-Bertani agar plates for 24 h. SF germinated more rapidly in a liquid medium with high NaCl concentrations than SC and SD, but became slower under alkaline conditions. Raman spectroscopy was used to analyze the heterogeneities in the three types of vegetative cells and their spores under different nutritional conditions. Exponentially grown-each vegetative cells had different overall Raman peak values. Raman peaks of SC, SD, and SF also showed differences in adenine and amide III compositions and nucleic acid contents. Our data along with Raman spectroscopy provided the evidence that spores formed under under different growth conditions possess very different cellular components, which affected their survival and germination rates.
关于细菌在不同营养条件下进行孢子形成时最终孢子成分知之甚少。在溶壁芽胞杆菌 YS11 的三种孢子（SD、在 Difco 孢子形成培养基中形成的孢子；SC 和 SF、分别在含有 10mM CaCl 和 10mM FeSO 的农业副产物培养基中形成的孢子）中观察到不同程度的抗性和发芽率。SF 具有更强的抗 UV 能力，在 UV 处理下比 SC 和 SD 的存活率高 1.8-2.3 倍。三种孢子类型在 80°C 时表现出相似的耐热性，但 SC 和 SD 的存活率比 SF 高约 1,000 倍，在 90°C 时则更高。然而，SF 的发芽能力在 Luria-Bertani 琼脂平板上 24 小时后比 SD 和 SC 高 20%。SF 在高 NaCl 浓度的液体培养基中比 SC 和 SD 发芽更快，但在碱性条件下则变慢。拉曼光谱用于分析不同营养条件下三种类型的营养细胞及其孢子的异质性。指数生长期的每个营养细胞具有不同的整体拉曼峰值。SC、SD 和 SF 的拉曼峰也显示出腺嘌呤和酰胺 III 组成和核酸含量的差异。我们的数据以及拉曼光谱提供了证据，表明在不同生长条件下形成的孢子具有非常不同的细胞成分，这影响了它们的存活率和发芽率。
