Difference Between 70S Ribosomes and 80S Ribosomes, RNA, Micromolecules

Difference Between 70S Ribosomes and 80S Ribosomes

	70S Ribosome	80S Ribosome
Presence	In prokaryotes (bacteria).	In eukaryotes (algae, fungi,higher plants and animals).
Sedimentation Coefficient Size	64S-72S (average 69S) Relatively smaller.	79-85S in fungi, 80S in mammals. Relatively larger.
Molecular wt.	4 million (4 x 106)	4 million (4 x 106)
Subunits	Small 30S and large 50S	Small 408 and large 60S
RNA	3 molecules of RN A : 16S RNA in 30S subunit 23S and 58 RNA in 50S subunit	4 molecules of RN A : 16S-18S RNA in 40S subunit. 25S-29S, 5.8S and 5S RNA in 60S subunit.
MW of RNA	16S RNA-550,000 23S RNA-l.100,000 5S RNA-40,000	18S RNA-700,000* 28S RNA-1.700,000* 5.8S RNA-51,000* 5S RNA-3,000.*
No. of proteins	21(S1-S21) in small subunit** 34(S1-L34) in large subunit Total in prokaryotes : 50.60 proteins.	33 in small subunit.* 49 in large subunit.* Total in eukaryotes: 70-80 proteins.
Average MW of protein	18,000.**	21,000.**
No. of amino acids	~8,000.	~16000.
RNA-Protein ratio	2:1	1:1
1st critical Mg++ level.	0.5 micromoles of Mg++ per micromoles of phosphorus	0.3-0.1 micromoles of Mg++ per micromoles of phosphorus
2st critical Mg++ level.	0.3 micromoles of Mg++ per micromoles of phosphorus	0.15 micromoles of Mg++ per micromoles of phosphorus.

Index >> Ribosomes >> Difference Between 70S Ribosomes and 80S Ribosomes