Open AccessNo Correlation between Native and Denatured Forms of tRNA Trp from Escherichia coli and the Resistant and Sensitive Molecules Characterised by Phosphorolysis
Author(s) -
THANG Minh Nguy,
BUCKINGHAM Richard Hugh,
DONDON Lilian
Publication year - 1975
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1975.tb04117.x
Subject(s) - phosphorolysis , polynucleotide phosphorylase , transfer rna , denaturation (fissile materials) , polynucleotide , escherichia coli , biology , biochemistry , amino acid , chemistry , enzyme , rna , purine nucleoside phosphorylase , purine , nuclear chemistry , gene
Some tRNA molecules in solution are sensitive to attack by polynucleotide phosphorylase while others are resistant, even with pure species of tRNA. Further analysis of this behaviour has revealed an underlying microheterogeneity in tRNA structure. In order to clarify the relation between the sensitive and resistant classes of tRNA, and the native and denatured forms with respect to amino acid acceptance, the phosphorolysis of tRNA Trp from Escherichia coli has been investigated. Native tRNA Trp is similar to species examined previously: resistant and sensitive classes are observed and the sensitive proportion increases with temperature. At 20°C both native and denatured tRNA Trp are stable under phosphorolysis conditions, and denatured tRNA Trp is found also to possess resistant and sensitive classes. About 10% of both native and denatured tRNA Trp is rapidly phosphorolysed at 20°C, but the rate of conversion of resistant denatured tRNA Trp to the sensitive class is about twice as fact as for the native form. Thus it can be concluded that the sensitive molecules of tRNA Trp attacked by polynucleotide phosphorylase are not due to denaturation.