Biomaterial Database

Purification and characterization of mitochondrial ribonuclease P from Aspergillus nidulans. 1996

Y C Lee, and B J Lee, and D S Hwang, and H S Kang

Department of Microbiology, College of Natural Sciences, Seoul National University, Korea.

Mitochondrial ribonuclease (RNase) P from Aspergillus nidulans was purified to near homogeneity using whole-cell extract as the starting material. A 4400-fold purification with a yield of 5.2% was achieved by ammonium sulfate fractionation, heat treatment, and five types of column chromatography, including tRNA-affinity column chromatography. This enzyme, which has a molecular mass of 232 kDa determined by glycerol gradient sedimentation analysis, appears to be composed of seven polypeptides and an RNA moiety. These seven polypeptides consistently copurified with the RNase P activity through two ion-exchange chromatography columns and in a glycerol gradient. As judged by nuclease sensitivity, the enzyme requires an RNA component for its activity. The 3'-end-labeled RNAs that copurified with the enzyme displayed identical sequences but had variable lengths for the 5' end, indicating that they originated from a common RNA molecule, the putative RNA component of RNase P. The purified enzyme cleaved mitochondrial precursor tRNAHis, resulting in an 8-bp acceptor stem. This implies that the purified RNase P is a mitochondrial enzyme and that an additional guanylate residue (at position -1) of tRNAHis in A. nidulans mitochondria is generated by a mode that is analogous to the generation of their counterparts in prokaryotes and chloroplasts.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008928	Mitochondria	Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)	Mitochondrial Contraction,Mitochondrion,Contraction, Mitochondrial,Contractions, Mitochondrial,Mitochondrial Contractions
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D009690	Nucleic Acid Conformation	The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.	DNA Conformation,RNA Conformation,Conformation, DNA,Conformation, Nucleic Acid,Conformation, RNA,Conformations, DNA,Conformations, Nucleic Acid,Conformations, RNA,DNA Conformations,Nucleic Acid Conformations,RNA Conformations
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D004722	Endoribonucleases	A family of enzymes that catalyze the endonucleolytic cleavage of RNA. It includes EC 3.1.26.-, EC 3.1.27.-, EC 3.1.30.-, and EC 3.1.31.-.	Endoribonuclease
D001233	Aspergillus nidulans	A species of imperfect fungi from which the antibiotic nidulin is obtained. Its teleomorph is Emericella nidulans.	Aspergillus nidulellus,Emericella nidulans
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D012322	RNA Precursors	RNA transcripts of the DNA that are in some unfinished stage of post-transcriptional processing (RNA PROCESSING, POST-TRANSCRIPTIONAL) required for function. RNA precursors may undergo several steps of RNA SPLICING during which the phosphodiester bonds at exon-intron boundaries are cleaved and the introns are excised. Consequently a new bond is formed between the ends of the exons. Resulting mature RNAs can then be used; for example, mature mRNA (RNA, MESSENGER) is used as a template for protein production.	Precursor RNA,Primary RNA Transcript,RNA, Messenger, Precursors,RNA, Ribosomal, Precursors,RNA, Small Nuclear, Precursors,RNA, Transfer, Precursors,Pre-mRNA,Pre-rRNA,Pre-snRNA,Pre-tRNA,Primary Transcript, RNA,RNA Precursor,mRNA Precursor,rRNA Precursor,snRNA Precursor,tRNA Precursor,Pre mRNA,Pre rRNA,Pre snRNA,Pre tRNA,Precursor, RNA,Precursor, mRNA,Precursor, rRNA,Precursor, snRNA,Precursor, tRNA,Precursors, RNA,RNA Primary Transcript,RNA Transcript, Primary,RNA, Precursor,Transcript, Primary RNA,Transcript, RNA Primary