Nitrogenase Interrelationship with Nodule Ureide and Lipid Components at Anthesis and Seed Maturity of Jack Bean

摘要

Nodule lipid, glyoxylate and ureide transformations associated with nitrogenase activity of Jack bean (Canavalia ensiformis(L.) DC.) were determined at anthesis, 72 day age from emergence (DAE), and with mature seed pod development at 149 DAE. Total nodule lipid content decreased about 86during seed development. Acylglycerides were dominant, 10.9 g kg−1nodule, with triacyl content decreasing from 55at anthesis to about 13at full seed set. Phosphatidylcholine composed about 39of total nodule glycerphosphatides, 9.03 g kg−1nodule at anthesis, decreasing to 16at full seed set. Oleic was the principal unsaturated fatty acid, 33.0at anthesis decreasing to 25.8at full seed set. Nitrogenase activity decreased from 617.8 nmol C2H4plant−1s−1at anthesis to 499.5 nmol C2H4plant−1s−1at full seed set. Key glyox-ylate cycle enzymes changed significantly with increase of isocitratase from 4.59 katal×10-6(μkat) kg−1to 18.36μkat kg−1nodule and decrease of malate synthetase from 32.47μkat kg−1to 4.25μkat kg−1nodule. Highly significant decreases occurred with purine catabolic enzymes; uricase decreased from 39.10μkat kg−1to 2.21μkat kg−1, allantoinase decreased from 4.08μkat kg−1to 1.36μkat kg−1and allantoicase decreased from 3.91μkat kg−1to 0.85μkat kg−1nodule. Ureide content decreased fro