Characterization of the germination kinetics of individual Nosema bombycis spores using phase contrast microscopy imaging and Raman spectroscopy

摘要

We used phase-contrast microscopy and laser tweezers Raman spectroscopy to monitor the changes of intracellular components during the spore germination of microsporidian Nosema bombycis under artificial conditions. The kinetics of image brightness of individual spores showed three-phase profile. The Raman intensities of trehalose, nucleic acid, and protein showed little changes prior to germination, but dramatically decreased once germinated, which was consistent with the kinetics of brightness of the spore. The time of spore germination (?T_(germ)) was essentially identical, but the initial time of germination (T_(lag)) showed obvious heterogeneity. These results demonstrate that the firing of the polar tube is not performed via trehalose transformation to the spore's osmosis during germination. Phase-contrast microscopy imaging and Raman spectroscopy provide a more comprehensive approach to understanding the germination of microsporidian spores.