Exoribonuclease from Saccharomyces cerevisiae: effect of modifications of 5' end groups on the hydrolysis of substrates to 5' mononucleotides

Journal Article · Thu Mar 30 04:00:00 EST 1978 · Biochem. Biophys. Res. Commun.; (United States)

DOI:https://doi.org/10.1016/0006-291X(78)91586-3· OSTI ID:6550273

Stevens, A

Using poly(A) as a substrate, an exoribonuclease has been purified from the high-salt wash of ribosomes of Saccharomyces cerevisiae. The product of the reaction of the exoribonuclease is 5' AMP. Hydrolysis of (/sup 3/H)(pA)/sub 3/(/sup 14/C)(pA)/sub n/ shows that both labels are released at the same rate, suggesting that the enzyme acts in a processive manner. Removal of the terminal phosphate of poly(A) with alkaline phosphatase reduces the rate of hydrolysis by 80%. Treatment of the terminally dephosphorylated poly(A) with polynucleotide kinase restores the activity. Two 5' capped mRNA's have been tested and they are hydrolyzed slowly, if at all, by the enzyme. In contrast, phage T4 mRNA, ribosomal RNA, and encephalomyocarditis viral RNA are hydrolyzed at greater than 50% of the rate of poly(A).

• Research Organization: Oak Ridge National Lab., TN
• OSTI ID: 6550273
• Journal Information: Biochem. Biophys. Res. Commun.; (United States), Journal Name: Biochem. Biophys. Res. Commun.; (United States) Vol. 81:2; ISSN BBRCA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
550300 -- Cytology
59 BASIC BIOLOGICAL SCIENCES
BIOCHEMISTRY
CARBON 14 COMPOUNDS
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHEMISTRY
DECOMPOSITION
ENZYMES
ESTERASES
FUNGI
HYDROLASES
HYDROLYSIS
LABELLED COMPOUNDS
LABELLING
LYSIS
MESSENGER-RNA
MICROORGANISMS
NUCLEIC ACIDS
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANOIDS
PHOSPHATASES
PHOSPHOTRANSFERASES
PLANTS
RIBOSOMES
RNA
RNA-ASE
SACCHAROMYCES
SACCHAROMYCES CEREVISIAE
SOLVOLYSIS
SUBSTRATES
TRANSFERASES
YEASTS