Amino acid sequence analysis and characterization of a ribonuclease from starfish Asterias amurensis
| Autor: | Hiroko Kobayashi, Tadashi Itagaki, Naomi Motoyoshi, Norio Inokuchi |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
0301 basic medicine
biology Molecular mass RNase P Chemistry Starfish RNA General Medicine Ribonuclease Pancreatic biology.organism_classification Biochemistry 03 medical and health sciences 030104 developmental biology Complementary DNA Asterias Endoribonucleases biology.protein Animals Ribonuclease Amino Acid Sequence Molecular Biology Peptide sequence Cysteine |
| Zdroj: | Journal of biochemistry. 160(3) |
| ISSN: | 1756-2651 |
| Popis: | The aim of this study was to phylogenetically characterize the location of the RNase T2 enzyme in the starfish (Asterias amurensis). We isolated an RNase T2 ribonuclease (RNase Aa) from the ovaries of starfish and determined its amino acid sequence by protein chemistry and cloning cDNA encoding RNase Aa. The isolated protein had 231 amino acid residues, a predicted molecular mass of 25,906 Da, and an optimal pH of 5.0. RNase Aa preferentially released guanylic acid from the RNA. The catalytic sites of the RNase T2 family are conserved in RNase Aa; furthermore, the distribution of the cysteine residues in RNase Aa is similar to that in other animal and plant T2 RNases. RNase Aa is cleaved at two points: 21 residues from the N-terminus and 29 residues from the C-terminus; however, both fragments may remain attached to the protein via disulfide bridges, leading to the maintenance of its conformation, as suggested by circular dichroism spectrum analysis. The phylogenetic analysis revealed that starfish RNase Aa is evolutionarily an intermediate between protozoan and oyster RNases. |
| Databáze: | OpenAIRE |
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