TRANSFER RNA, III. RECONSTITUTION OF ALANINE ACCEPTOR ACTIVITY FROM FRAGMENTS PRODUCED BY SPECIFIC CLEAVAGE OF tRNAAlaII AT ITS ANTICODON*,†
Abstract
This report describes experiments showing that tRNAAla II can be cleaved specifically at the G residue of its anticodon to give “half” molecules in high yield. Neither of these fragments has alanine-acceptor activity, but this activity can be reconstituted by mixing the fragments in the presence of Mg+2. In dilute salt, on the other hand, the active complex dissociates spontaneously at 25° into the two fragments. Thus, both “halves” of tRNAAla II are necessary for acceptor activity and, in the presence of Mg+2, combination of these fragments to give an active duplex is thermodynamically favorable.
Footnotes
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↵ ‡ Fulbright fellow on leave from the University of Tokyo.
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↵ § USPHS training grant fellow (5 T05 GM-1668).
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↵ ** Career Research Scientist of the Health Research Council of the City of New York (I-200), to whom reprint requests should be sent.
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↵ * Part II: Schulman, L. H., and R. W. Chambers, these PROCEEDINGS, 61, 308 (1968).
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↵ † This work was supported by grants from USPHS (6 GM-07262) and the American Cancer Society (P-476).
