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Updated: Aug 18, 2026

Visualization of Germinosomes and the Inner Membrane in Bacillus subtilis Spores
Published on: April 15, 2019
In situ determination of refractive index and size of Bacillus spores by light transmission
A Katz1, Alexandra Alimova, M Xu
1Department of Physics, The City College of New York, New York, New York 10031, USA. akatz@ccny.cuny.edu
Abstract:
Light-extinction measurements in the wavelength range of 400 to 1000 nm are performed in situ on Bacillus subtilis endospores during heat-shock-induced activation. Simultaneous information on particle size and refractive indices during activation is calculated from the transmission spectra by use of the Gaussian ray approximation of anomalous diffraction theory. During activation the refractive index of the core decreases from 1.51 to 1.39, and the size increases from 0.38 to 0.6 microm.
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