Abstract
Both 1 and 2 dimensional peptide mapping techniques were used to compare the 180 kdalton subunits from maize chloroplast and type II nuclear DNA-dependent RNA polymerases (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6). Despite their similar molecular mass, these 180 kdalton subunits are not the same. Also, 2-dimensional tryptic maps of the 160, 43 and 28 kdalton polypeptides from maize type II nuclear RNA polymerase and of the 140, 42 and 27 kdalton polypeptides from maize chloroplast RNA polymerase show that each of these 6 polypeptides is unique.