TY - JOUR
T1 - When Ends Meet
T2 - Circular DNA Stretches Differently in Elongational Flows
AU - Li, Yanfei
AU - Hsiao, Kai Wen
AU - Brockman, Christopher A.
AU - Yates, Daniel Y.
AU - Robertson-Anderson, Rae M.
AU - Kornfield, Julia A.
AU - San Francisco, Michael J.
AU - Schroeder, Charles M.
AU - McKenna, Gregory B.
N1 - Publisher Copyright:
© 2015 American Chemical Society.
PY - 2015/8/25
Y1 - 2015/8/25
N2 - Chain topology has a profound impact on the flow behavior of single macromolecules. For circular polymers, the absence of free ends results in a unique chain architecture compared to linear or branched chains, thereby generating distinct molecular dynamics. Here, we report the direct observation of circular DNA dynamics in transient and steady flows for molecular sizes spanning the range of 25.0-114.8 kilobase pairs (kbp). Our results show that the longest relaxation times of the rings follow a power-law scaling relation with molecular weight that differs from that of linear chains. Also, relative to their linear counterparts, circular DNA molecules show a shifted coil-to-stretch transition and less diverse "molecular individualism" behavior as evidenced by their conformational stretching pathways. These results show the impact of chain topology on dynamics and reveal commonalities in the steady state behavior of circular and linear DNA that extends beyond chain architecture. (Figure Presented).
AB - Chain topology has a profound impact on the flow behavior of single macromolecules. For circular polymers, the absence of free ends results in a unique chain architecture compared to linear or branched chains, thereby generating distinct molecular dynamics. Here, we report the direct observation of circular DNA dynamics in transient and steady flows for molecular sizes spanning the range of 25.0-114.8 kilobase pairs (kbp). Our results show that the longest relaxation times of the rings follow a power-law scaling relation with molecular weight that differs from that of linear chains. Also, relative to their linear counterparts, circular DNA molecules show a shifted coil-to-stretch transition and less diverse "molecular individualism" behavior as evidenced by their conformational stretching pathways. These results show the impact of chain topology on dynamics and reveal commonalities in the steady state behavior of circular and linear DNA that extends beyond chain architecture. (Figure Presented).
UR - http://www.scopus.com/inward/record.url?scp=84940099208&partnerID=8YFLogxK
U2 - 10.1021/acs.macromol.5b01374
DO - 10.1021/acs.macromol.5b01374
M3 - Article
AN - SCOPUS:84940099208
SN - 0024-9297
VL - 48
SP - 5997
EP - 6001
JO - Macromolecules
JF - Macromolecules
IS - 16
ER -