The aminoacylation of structurally variant phenylalanine tRNAs from mitochondria and various nonmitochondrial sources by bovine mitochondrial phenylalanyl-tRNA synthetase.
Bovine mitochondrial (mt) phenylalanine tRNA (tRNAPhe) was purified on a large scale using a new hybridization assay method developed by the authors. Although its melting profile suggested a loose higher order structure, presumably influenced by the apparent loss of D loop-T loop interaction necessary for forming a rigid L-shaped tertiary structure, its aminoacylation capacity catalyzed by mt phenylalanyl-tRNA synthetase (PheRS) was nearly equal to that of Escherichia coli tRNAPhe. Misaminoacylation was not observed for the mt tRNAPhe-mt PheRS system. Comparing the aminoacylation efficiencies of several combinations of tRNAPheS and PheRSs from various sources, including bovine mitochondria, bovine and yeast cytosols, E. coli, Thermus thermophilus, and Sulfolobus acidocaldarius, it was clarified that mt PheRS was able to aminoacylate all the above mentioned tRNAPhe species, albeit with varying degrees of efficiency. This broad charging spectrum suggests that mt PheRS possesses a relatively simple recognition mechanism toward its substrate, tRNAPhe.
Kumazawa
Y
Y
Department of Industrial Chemistry, Faculty of Engineering, University of Tokyo, Japan.
Yokogawa
T
T
Hasegawa
E
E
Miura
K
K
Watanabe
K
K
D000215:Acylation; D000604:Amino Acyl-tRNA Synthetases / Q000502:physiology*; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D015342:DNA Probes; D014644:Genetic Variation; D008930:Mitochondria, Liver / Q000201:enzymology / Q000378:metabolism*; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010652:Phenylalanine-tRNA Ligase / Q000235:genetics / Q000502:physiology*; D012313:RNA / Q000378:metabolism*; D000077278:RNA, Mitochondrial; D012345:RNA, Transfer, Amino Acid-Specific / Q000235:genetics*; D012360:RNA, Transfer, Phe / Q000235:genetics* / Q000378:metabolism; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D013816:Thermodynamics
D015342:DNA Probes; D000077278:RNA, Mitochondrial; D012345:RNA, Transfer, Amino Acid-Specific; D012360:RNA, Transfer, Phe; D012313:RNA; D000604:Amino Acyl-tRNA Synthetases; D010652:Phenylalanine-tRNA Ligase