PUB - Publikationen an der Universität Bielefeld

A full-length cDNA obtained from a vicia faba L. root nodule library [Plant Mol. Biol. 22 (1993) 957] which coded for the broad bean nodulin NVf32 was overexpressed in E. coli. The recombinant protein was purified under denaturing and native conditions. Native preparations were used for various enzymatic assays towards a chininase-like activity, which did not reveal any positive results. A highly specific antiserum was induced in rabbits by a preparation of denatured NVf32 protein. NVf32 could be detected only in root nodules of a minor fraction of the examined population. Though the genome of all individuals under examination contained VfNOD32 sequences, the occurrence of the protein seemed to be correlated with the presence of an additional copy of the gene. Immunohistology and Northern blotting confirmed the consistency of protein and RNA data. In nodules transcribing the VfNOD32 gene the protein accounts for up to 10% of the total protein. No detectable phenotype could be assigned to the presence of this nodulin. These data together with the well-documented homologies of NVf32 to the seed protein narbonin suggest that NVf32 does not carry out a function essential for nodule organogenesis or nitrogen fixation. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.