Biomaterial Database

Yeast proteinase yscB inactivates the leucyl tRNA synthetase in extracts of Saccharomyces cerevisiae. 1991

I F Larrinoa, and C F Heredia

Instituto de Investigaciones Biomédicas del CSIC, Facultad de Medicina de la UAM, Madrid, Spain.

The aminoacyl-tRNA synthetases are inactivated in extracts of Saccharomyces cerevisiae preferentially to other yeast enzymes and the rate of inactivation greatly increases in extracts of nitrogen-starved cells. The intensity of inactivation varies for the different synthetases. Under conditions in which more than 80 per cent of the leucyl and isoleucyl-tRNA synthetases are inactivated, the activities of the synthetases for serine and arginine remain unchanged and the synthetases for other amino acids are inactivated to different extents. We have analyzed the characteristics of inactivation of the leucyl-tRNA synthetase, and identified the inactivating agent as the yeast proteinase yscB by the following criteria: co-induction of both activities by nitrogen starvation; same pattern of sensitivity to yeast proteinase inhibitors; co-purification through a procedure designed to purify the proteinase yscB and lack of inactivating activity in extracts of a nitrogen-starved yeast mutant lacking proteinase yscB.

UI	MeSH Term	Description	Entries
D007935	Leucine-tRNA Ligase	An enzyme that activates leucine with its specific transfer RNA. EC 6.1.1.4.	Leucyl T RNA Synthetase,Leu-tRNA Ligase,Leucine-tRNA Synthetase,Leu tRNA Ligase,Leucine tRNA Ligase,Leucine tRNA Synthetase,Ligase, Leu-tRNA,Ligase, Leucine-tRNA,Synthetase, Leucine-tRNA
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D009584	Nitrogen	An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
D011480	Protease Inhibitors	Compounds which inhibit or antagonize biosynthesis or actions of proteases (ENDOPEPTIDASES).	Antiprotease,Endopeptidase Inhibitor,Endopeptidase Inhibitors,Peptidase Inhibitor,Peptidase Inhibitors,Peptide Hydrolase Inhibitor,Peptide Hydrolase Inhibitors,Peptide Peptidohydrolase Inhibitor,Peptide Peptidohydrolase Inhibitors,Protease Antagonist,Protease Antagonists,Antiproteases,Protease Inhibitor,Antagonist, Protease,Antagonists, Protease,Hydrolase Inhibitor, Peptide,Hydrolase Inhibitors, Peptide,Inhibitor, Endopeptidase,Inhibitor, Peptidase,Inhibitor, Peptide Hydrolase,Inhibitor, Peptide Peptidohydrolase,Inhibitor, Protease,Inhibitors, Endopeptidase,Inhibitors, Peptidase,Inhibitors, Peptide Hydrolase,Inhibitors, Peptide Peptidohydrolase,Inhibitors, Protease,Peptidohydrolase Inhibitor, Peptide,Peptidohydrolase Inhibitors, Peptide
D012441	Saccharomyces cerevisiae	A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.	Baker's Yeast,Brewer's Yeast,Candida robusta,S. cerevisiae,Saccharomyces capensis,Saccharomyces italicus,Saccharomyces oviformis,Saccharomyces uvarum var. melibiosus,Yeast, Baker's,Yeast, Brewer's,Baker Yeast,S cerevisiae,Baker's Yeasts,Yeast, Baker
D012697	Serine Endopeptidases	Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.	Serine Endopeptidase,Endopeptidase, Serine,Endopeptidases, Serine