title: Minor conformational changes of yeast tRNAPhe anticodon loop occur upon aminoacylation as indicated by Y base fluorescence.
abstract: The Y base fluorescence of highly purified yeast tRNAPhe was measured in order to detect possible conformational changes of the anticodon loop, which were induced as a consequence of aminoacylation. A small enhancement of Y base fluorescence intensity in the order of 5% was observed in situ during aminoacylation. The rotational mobility of the Y base of Phe-tRNAPhe and tRNAPhe was determined by measuring the fluorescence polarization at various temperatures between 5 degrees C and 35 degrees C. Differences in the fluorescence polarization of the Y base between these tRNAs were however not observed. These results confirm that minor changes in the microenvironment of the Y base occur upon aminoacylation, whereas significant conformational changes of the anticodon loop can be excluded.
mesh_terms: D000926:Anticodon / Q000378:metabolism*; D005454:Fluorescence Polarization; D006147:Guanine / Q000031:analogs & derivatives*; D008274:Magnesium / Q000494:pharmacology; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D010649:Phenylalanine / Q000378:metabolism; D010652:Phenylalanine-tRNA Ligase / Q000378:metabolism; D012343:RNA, Transfer / Q000378:metabolism*; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000032:analysis*
chemical_list: D000926:Anticodon; D012346:RNA, Transfer, Amino Acyl; C012099:wye; D010649:Phenylalanine; D006147:Guanine; D012343:RNA, Transfer; D010652:Phenylalanine-tRNA Ligase; D008274:Magnesium