Changes of aspartate aminotransferase activity, its isoform pattern, and free amino acids content in peanut cotyledons during seed germination

After imbibition of peanut seeds, the concentration of free amino acids in cotyledons increases probably due to hydrolysis of reserve proteins. That i ncrease was accompanied by a stimulation of aspartate aminotransferase (AAT , EC 1.6. 1.1) activity especially pronounced between first and sixth day o f imbibition. peanut cotyledons contained several AAT isoforms which could be visualized after polyacrylamide gel electrophoresis (PAGE). Native PAGE of extracts item cotyledons of dry seeds demonstrate three active bonds. Th e intensity of these bands increased reaching a maximum after 6th day of im bibition. An additional band appears transientely on 6th day, but is not vi sible after 14 days of incubation. A fastest band appears on this latter da y. IT germination takes place under hypersalinity conditions, the AAT activ ity severely diminishes and the free amino acid concentration raises. The p ossibilities of different types of AAT regulation are discussed.