GENETIC AND MOLECULAR ANALYSIS OF ERWINIA AMYLOVORA EPS ENCODING GENES

M. Menggad, J. Laurent, J. Paulin
Among our set of single insertion mutants altered in the ability to elicitate fire blight, PMV6089 is an acapsular mutant which does not map in the large hrp cluster. The insertion mutation was cloned and cosmids containing wild-type genomic inserts hybridizing with the mutation flanking sequence were isolated. Two cosmids were able to restore pathogenicity to PMV6089 on pear and apple seedlings. When the length of the cloned fragment was reduced from 20 kb to 8.4 kb, the cosmid was still able to complement PMV6089. The 8.4 kb fragment was cloned in both orientations in pRK767 down stream of P-lac. Only one resulting plasmid was able to complement the mutation, thus identifying the transcription orientation of one pathogenicity important locus. In addition, the 8.4 kb fragment which encodes amylovoran production was mutagenized with transposon Tn3-GUS. By reverse genetics, we constructed new mutants within this region which will be useful to further characterize this region.
Menggad, M., Laurent, J. and Paulin, J. (1993). GENETIC AND MOLECULAR ANALYSIS OF ERWINIA AMYLOVORA EPS ENCODING GENES. Acta Hortic. 338, 263-264
DOI: 10.17660/ActaHortic.1993.338.40
https://doi.org/10.17660/ActaHortic.1993.338.40

Acta Horticulturae