title: Comparison of base inclination of ribo-GC and deoxyribo-GC polymers, and synthesis of poly(rGrC)-poly(rGrC).
abstract: The inclination angle between the base normal and the helix axis, and the axes around which the bases incline, are measured for ribo-GC polymers in buffer by using flow linear dichroism (LD), and compared to measurements for deoxyribo-GC polymers in buffer and under dehydrating conditions. A new method is designed to synthesize poly(rGrC)-poly(rGrC), which is not available commercially, in large quantities. The LD of this RNA reveals inclination angles that are similar to the B-form DNA in buffer, although the axes are different. The CD of poly(dGdC)-poly(dGdC) under the dehydrating conditions is similar to poly(rGrC)-poly(rGrC), indicating it is in the A form, and the LD gives larger inclination angles than either the B form or the corresponding RNA. Poly(dG)-poly(dC) is in the A form in buffer. Comparison among poly(rG)-poly(rC) in buffer, and poly(dG)-poly(dC) in buffer under dehydrating conditions, reveals similar inclination angles and axes, although the LD shows that the DNA has the largest inclination angles. Except for poly(rGrC)-poly(rGrC), which has a unique reduced dichroism, all the axes for G are similar, as are the axes for C.
authors.affiliation: Department of Biochemistry and Biophysics, Oregon State University, Corvallis 97331-7305, USA.
authors.forename: X
authors.initials: X
authors.lastname: Jin
authors.forename: W C
authors.initials: WC
authors.lastname: Johnson
mesh_terms: D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry; D009690:Nucleic Acid Conformation; D011066:Poly C / Q000737:chemistry*; D011068:Poly G / Q000737:chemistry*; D011089:Polydeoxyribonucleotides / Q000737:chemistry*; D011131:Polyribonucleotides / Q000138:chemical synthesis* / Q000737:chemistry*; D012313:RNA / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013329:Structure-Activity Relationship
chemical_list: D011089:Polydeoxyribonucleotides; D011131:Polyribonucleotides; C095662:poly(rG-rC); D011068:Poly G; C008961:poly G-poly C; C019530:poly(dC-dG); D011066:Poly C; D012313:RNA; D004247:DNA