Leucyl-transfer ribonucleic acid synthetase in senescing tobacco leaves

[摘要]

1. The activity of leucyl-tRNA synthetase obtained from tobacco leaves declined by 50% over a period of 4 days senescence induced by detachment. In addition tRNA^Leu from senescing leaves was charged to a lesser extent than tRNA^Leu extracted from mature leaves immediately after detachment. 2. tRNA^Leu was charged with a synthetase preparation from either mature or senescent leaves and chromatographed on an RPC 3 column. The elution profile showed that the marked decline in specific activity of leucyl-tRNA synthetase in senescent leaves was not associated with a loss of acylation of any isoacceptor of tRNA^Leu.