Deinococcus radiodurans is a potent radiation resistant bacterium with immense potential in nuclear waste treatment. In this investigation, the translational and rotational dynamics of dilute suspensions of D. radiodurans cultured under controlled growth conditions was studied by the polarized and depolarized dynamic light-scattering (DLS) techniques. Additionally, confocal laser scanning microscopy was used for characterizing the cultured samples and also for identification of D. radiodurans dimer, tetramer, and multimer morphologies. The data obtained showed translational diffusion coefficients (DT) of 1.2 x 10(-9), 1.97 x 10(-9), and 2.12 x 10(-9) cm2 /s, corresponding to an average size of 3.61, 2.22, and 2.06 microm, respectively, for live multimer, tetramer, and dimer forms of D. radiodurans. Depolarized DLS experiments showed very slow rotational diffusion coefficients (DR) of 0.182/s for dimer and 0.098/s for tetramer morphologies. No measurable rotational diffusion was observed for multimer form. Polarized DLS measurements on live D. radiodurans confirmed that the bacterium is nonmotile in nature. The dynamics of the dead dimer and tetramer D. radiodurans were also studied using polarized and depolarized DLS experiments and compared with the dynamics of live species. The dead cells were slightly smaller in size when compared to the live cells. However, no additional information could be obtained for dead cells from the polarized and depolarized dynamic light-scattering studies.
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http://dx.doi.org/10.1529/biophysj.106.086520 | DOI Listing |
Int J Mol Sci
December 2024
Department of Advanced Prosthodontics, Graduate School of Medical and Dental Sciences, Institute of Science Tokyo, Yushima, Tokyo 1138549, Japan.
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January 2025
Departments of Ophthalmology, The University of Texas Southwestern Medical Center, Dallas, Texas, USA.
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View Article and Find Full Text PDFNat Commun
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International Centre for Quantum Materials, Collaborative Innovation Centre of Quantum Matter, Peking University, Beijing, China.
The anomalous photovoltaic effect (APE) in polar crystals is a promising avenue for overcoming the energy conversion efficiency limits of conventional photoelectric devices utilizing p-n junction architectures. To facilitate effective photocarrier separation and enhance the APE, polar materials need to be thinned down to maximize the depolarization field. Here, we demonstrate Janus MoSSe monolayers (~0.
View Article and Find Full Text PDFJ Phys Chem Lett
January 2025
Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics and School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China.
The most distinctive features of ferroelectrics are spontaneous polarization and depolarization. Ferroelectricity was first observed in Rochelle salt, a compound with a chiral component in which the molecular chirality is not affected by depolarization. For structurally chiral ferroelectrics (SCFs), such as triglycine sulfate, which lacks chiral components, the depolarization effect on chirality presents an intriguing and unexplored topic.
View Article and Find Full Text PDFNatl Sci Rev
January 2025
State Key Laboratory of Physical Chemistry of Solid Surfaces, School of Electronic Science and Engineering, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
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