TY  - JOUR
AU  - Kang, Kyongok
AU  - Ma, Yue
AU  - Sadakane, Koichiro
TI  - Direct visualization of local activities of long DNA strands via image–time correlation
JO  - European biophysics journal
VL  - 50
IS  - 8
SN  - 0175-7571
CY  - New York
PB  - Springer
M1  - FZJ-2021-05932
SP  - 1139 - 1155
PY  - 2021
AB  - Bacteriophages with long DNA genomes are of interest due to their diverse mutations dependent on environmental factors. By lowering the ionic strength of a hydrophobic (PPh4Cl) antagonistic salt (at 1 mM), single long T4 DNA strand fluctuations were clearly observed, while condensed states of T4 DNA globules were formed above 5–10 mM salt. These long DNA strands were treated with fluorescently labeled probes, for which photo bleaching is often unavoidable over a short time of measurement. In addition, long (few tens of μm) length scales are required to have larger fields of view for better sampling, with shorter temporal resolutions. Thus, an optimization between length and time is crucial to obtain useful information. To facilitate the challenge of detecting large biomacromolecules, we here introduce an effective method of live image data analysis for direct visualization and quantification of local thermal fluctuations. The motions of various conformations for the motile long DNA strands were examined for the single- and multi-T4 DNA strands. We find that the unique correlation functions exhibit a relatively high-frequency oscillatory behavior superimposed on the overall slower decay of the correlation function with a splitting of amplitudes deriving from local activities of the long DNA strands. This work shows not only the usefulness of an image–time correlation for analyzing large biomacromolecules, but also provides insight into the effects of a hydrophobic antagonistic salt on active T4 bacteriophage long DNA strands, including thermal translocations in their electrostatic interactions.
LB  - PUB:(DE-HGF)16
C6  - pmid:34499211
UR  - <Go to ISI:>//WOS:000694572400001
DO  - DOI:10.1007/s00249-021-01570-0
UR  - https://juser.fz-juelich.de/record/904362
ER  -