Isolation and physiochemical properties of protein-rich nematode mitochondrial ribosomes.
In the present study, mitochondrial ribosomes of the nematode Ascaris suum were isolated and their physiochemical properties were compared to ribosomes of Escherichia coli. The sedimentation coefficient and buoyant density of A. suum mitochondrial ribosomes were determined. The sedimentation coefficient of the intact monosome was about 55 S. The buoyant density of formaldehyde-fixed ribosomes in cesium chloride was 1.40 g/cm(3), which suggests that the nematode mitoribosomes have a much higher protein composition than other mitoribosomes. The diffusion coefficients obtained from dynamic light scattering measurements were (1.48 +/- 0.04) x 10(-)(7) cm(2) s(-)(1) for 55 S mitoribosomes and (1.74 +/- 0.04) x 10(-)(7) cm(2) s(-)(1) for the 70 S E. coli monosome. The diameter of mitoribosomes was measured by dynamic light-scattering analysis and electron microscopy. Though the nematode mitoribosome has a larger size than the bacterial ribosome, it does not differ significantly in size from mammalian mitoribosomes.
Zhao
Feng
F
Department of Integrated Biosciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
Ohtsuki
Takashi
T
Yamada
Koji
K
Yoshinari
Shigeo
S
Kita
Kiyoshi
K
Watanabe
Yoh-Ichi
Y
Watanabe
Kimitsuna
K
D000818:Animals; D017165:Ascaris suum / Q000737:chemistry* / Q000166:cytology*; D002499:Centrifugation, Density Gradient; D004926:Escherichia coli / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D008928:Mitochondria / Q000737:chemistry* / Q000648:ultrastructure; D012269:Ribosomal Proteins / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism / Q000648:ultrastructure; D012270:Ribosomes / Q000737:chemistry* / Q000378:metabolism* / Q000648:ultrastructure; D013057:Spectrum Analysis
D012269:Ribosomal Proteins