TY - JOUR
T1 - Vacuum UV CD spectra of homopolymer duplexes and triplexes containing A.T or A.U base pairs
AU - Johnson, Kenneth H.
AU - Gray, Donald M.
AU - Sutherland, John C.
N1 - Funding Information:
We are grateful for support from NIH Research Grants GM-19060 (to DMG) and GM-35662 (to JCS), Grant AT-503 from the Robert A.Welch Foundation (to DMG), the Office of Health and Environmental Research, USDOE (JCS), and the NSLS-HFBR Faculty-Student Support Program. The NSLS is supported by the Office of Energy Research, USDOE.
PY - 1991/5/11
Y1 - 1991/5/11
N2 - Vacuum UV circular dlchroism (CD) spectra were measured down to 174 nm for five homopolymers, five duplexes, and four triplexes containing adenlne, uracll, and thymine. Near 190 nm, the CD bands of poly[d(A)] and poly[r(A)] were larger than the CD bands of the polypyrlmidlnes, poly[d(T)], poly[d(U)], and poly[r(U)]. Little change was observed In the 190 nm region upon formation of the duplexes (poly[d(A)-d(T)], poly[d(A)-d(U)], poly[r(A)-d(T)], poly[r(A)-d(U)], and poly[r(A) r(U)]) or upon formation of two of the triplexes (poly[d(T)-d(A)-d(T)] and poly[d(U) d(A) d(U)]). This showed that the purine strand had the same or a similar structure in these duplexes and triplexes as when free in solution. Both A-U and A-T base pairing Induced positive bands at 177 and 202 nm. For three triplexes containing poly[d(A)], the formation of a triplex from a duplex and a free pyrimidine strand induced a negative band centered between 210 and 215 nm. The Induction of a band between 210 and 215 nm indicated that these triplexes had aspects of the A conformation.
AB - Vacuum UV circular dlchroism (CD) spectra were measured down to 174 nm for five homopolymers, five duplexes, and four triplexes containing adenlne, uracll, and thymine. Near 190 nm, the CD bands of poly[d(A)] and poly[r(A)] were larger than the CD bands of the polypyrlmidlnes, poly[d(T)], poly[d(U)], and poly[r(U)]. Little change was observed In the 190 nm region upon formation of the duplexes (poly[d(A)-d(T)], poly[d(A)-d(U)], poly[r(A)-d(T)], poly[r(A)-d(U)], and poly[r(A) r(U)]) or upon formation of two of the triplexes (poly[d(T)-d(A)-d(T)] and poly[d(U) d(A) d(U)]). This showed that the purine strand had the same or a similar structure in these duplexes and triplexes as when free in solution. Both A-U and A-T base pairing Induced positive bands at 177 and 202 nm. For three triplexes containing poly[d(A)], the formation of a triplex from a duplex and a free pyrimidine strand induced a negative band centered between 210 and 215 nm. The Induction of a band between 210 and 215 nm indicated that these triplexes had aspects of the A conformation.
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U2 - 10.1093/nar/19.9.2275
DO - 10.1093/nar/19.9.2275
M3 - Article
C2 - 2041768
AN - SCOPUS:0025898636
SN - 0305-1048
VL - 19
SP - 2275
EP - 2280
JO - Nucleic Acids Research
JF - Nucleic Acids Research
IS - 9
ER -