Tissue proteins of some cryptogams: the amide, tyrosine and tryptophan contents

Abstract

The amide, tyrosine and tryptophan contents of protein prepns. from the photosynthesizing tissues, expressed as % of the protein-N, were respectively 5.52, 2.43 and 1.7 for Lunularia cruciata, 4.92-5.14, 2.06-25 and 1.13-1.19 for Pteridium aquilinum, and 531, 2.6 and 1.43 for Selaginella sp. These values are of much the same magnitude as those obtained with leaf proteins of the angiosperms, but the tryptophan contents of the P. aquilinum prepns. are lower than any encountered heretofore. The amide, tyrosine and tryptophan contents of protein prepns. from leaves of Trifolium subterraneum were 5.29-5.39, 2.53-2.64 and 1.62-1.75 respectively, as % of the protein-N (similar to other legumes), and the amide content of the petiole protein was 5.91.