Effect of uridine dethiolation in the anticodon triplet of tRNA(Glu) on its association with tRNA(Phe).
The effect of U(34) dethiolation on the anticodon-anticodon association between E. coli tRNA(Glu) and yeast tRNA(Phe) has been studied by the temperature jump relaxation technique. An important destabilization upon replacement of the thioketo group of s2U(34) by a keto group, was revealed by a lowering of melting temperature of about 20 degrees C. The measured kinetic parameters indicated that this destabilization effect was originated in an increase of dissociation and a decrease of association rate constants by a factor of 4 to 5. Modifications in both stacking interactions and flexibility in the anticodon loop would be responsible for this effect.
Houssier
C
C
Laboratoire de Chimie Macromoléculaire et Chimie Physique, Université de Liège, Belgium.
Degée
P
P
Nicoghosian
K
K
Grosjean
H
H
D000926:Anticodon / Q000378:metabolism* / Q000648:ultrastructure; D002942:Circular Dichroism; D009691:Nucleic Acid Denaturation; D012329:RNA, Bacterial / Q000378:metabolism; D012331:RNA, Fungal / Q000378:metabolism; D012343:RNA, Transfer / Q000378:metabolism*; D012345:RNA, Transfer, Amino Acid-Specific / Q000378:metabolism*; D012352:RNA, Transfer, Glu / Q000378:metabolism*; D012360:RNA, Transfer, Phe / Q000378:metabolism*; D013891:Thiouridine
D000926:Anticodon; D012329:RNA, Bacterial; D012331:RNA, Fungal; D012345:RNA, Transfer, Amino Acid-Specific; D012352:RNA, Transfer, Glu; D012360:RNA, Transfer, Phe; D013891:Thiouridine; D012343:RNA, Transfer