The ultraviolet spectrum of deoxyribonucleic acids and their constituents

Protonated Polynucleotide Structures

“…Biochem., Vol. 6 in contrast to the absorbance data, where cytidine and guanosine give similar changes [8].…”

“…Hypochromism 250 mp and hyperchromism a t 280 mp. have been observed during acidification of dGMP [8], poly (G) and poly (G). poly (C) [lo, 111 and during the formation of the semiprotonated complex of poly (C) [17,40,41].…”

“…Three possible structures seem to be feasible: Nearly all of the many investigations on the titration behaviour of DNA have attributed the accompanying phenomena to the protonation of cytidine residues [l-61. Since most of these results are based primarily upon ultraviolet absorbance changes, it appears legitimate to ask, (a) if other bases than cytidine could behave in such a way as to cause similar spectral changes [7,8] and thus take part in the protonation of DNA, and (b) if ultraviolet spectrophotometry in general is a sensitive enough technique to study the problem of DNA titration.Recent work on the optical properties of dGMP this study was in progress our attention was drawn to two preliminary communications by Luck and Zimmer [13] concerning this additional Cotton effect at about 265 mp which is studied in more detail in the present paper. The data presented here indicate that guanine is at least partly responsible for the titration behaviour of DNA.…”

“…Three possible structures seem to be feasible: Nearly all of the many investigations on the titration behaviour of DNA have attributed the accompanying phenomena to the protonation of cytidine residues [l-61. Since most of these results are based primarily upon ultraviolet absorbance changes, it appears legitimate to ask, (a) if other bases than cytidine could behave in such a way as to cause similar spectral changes [7,8] and thus take part in the protonation of DNA, and (b) if ultraviolet spectrophotometry in general is a sensitive enough technique to study the problem of DNA titration.…”

DNA base composition of strains in the genera Rhodosporidium, Cystofilobasidium, and Rhodotorula determined by reversed-phase high-performance liquid chromatography.

“…Direct or indirect methods of determining guanine plus cytosine (G + C) content have been reported (1)(2)(3)(4)(5)(6)(7). Most investigators (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)) use the thermal denaturation (Tm) method with the formula of MARMUR and DoTY (2) because the reproducibility of the Tm method, which was an indirect determination, was better than that of the direct method, e.g., UV absorption spectrum of the enzymatic hydrolyzate of DNA (5).…”