[Phenylalanyl-tRNA-synthase from human placenta: isolation and characteristics].
Phenylalanyl-tRNA synthetase (EC 6.1.1.20) from human placenta was isolated and purified using fractionation with polyethyleneglycol and chromatography on hydroxylapatite, heparin-Sepharose and mono-S. The enzyme purified 14800-fold with a 8% yield had a specific activity of 260 U./mg. The molecular mass of the native enzyme as determined by gel filtration was 270 +/- 13 kDa. The molecular masses of the enzyme subunits according to SDS-PAGE data were 74 +/- 4 kDa (alpha-subunit) and 63 +/- 3 (beta-subunit). The Km values for tRNA, ATP and phenylalanine in the aminoacylation reaction were 6.6 X 10(-8) M, 8.3 X 10(-5) M and 5.8 X 10(-6) M, respectively.
Zakharova
O D
OD
Kotenko
Iu G
IuG
Lavrik
O I
OI
D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D007700:Kinetics; D008970:Molecular Weight; D010652:Phenylalanine-tRNA Ligase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy
D010652:Phenylalanine-tRNA Ligase
Fenilalanil-tRNK-sintetaza iz platsenty cheloveka: vydelenie i kharakteristika.