STUDIES OF LIGNIN BIOSYNTHESIS USING ISOTOPIC CARBON: IX. TAXONOMIC DISTRIBUTION OF THE ABILITY TO UTILIZE TYROSINE IN LIGNIFICATION

Abstract

A survey of various plant species for the ability to utilize L-tyrosine as a lignin precursor has been extended, and the results obtained on a total of 21 species, representing seven families of monocotyledons and five of dicotyledons, are presented. Only grasses were able to convert L-tyrosine and L-phenylalanine to lignin with about equal efficiency, although two members of the Compositae and possibly one monocotyledon, Triglochin maritima, showed evidence of some ability to utilize tyrosine. One species of Juncus, J. nodosus, was unable to use phenylalanine efficiently and another, J. balticus, yielded conflicting results with regard to the utilization of both compounds. The findings are discussed in relation to known lignification pathways and taxonomic relationships.