Presence of the penicillin gene cluster in P. nalgiovense isolates.
Hybridization signals with the 7.2-kb pcbC-penDE probe,
corresponding to the penicillin genes, appeared in all P. nalgiovense
isolates (all of them shown previously to be penicillin
producers) but were absent in a Penicillium subgenus Penicillium
isolate which did not produce the antibiotic (Fig. 3).
Organization of the penicillin biosynthesis gene cluster in P.
nalgiovense isolates. Hybridization signals common to P. nalgiovense
and P. chrysogenum in BamHI and EcoRI fragments
indicated that the three penicillin biosynthetic genes are clustered
in P. nalgiovense and that many restriction sites are conserved
within the cluster in P. nalgiovense compared to P.
chrysogenum. Taking into account the hybridization patterns of
both species, we constructed a restriction map of the P. nalgiovense
cluster (Fig. 4). Most BamHI and EcoRI sites were
conserved in the mapped region with respect to P. chrysogenum,
while a new EcoRI site appeared in the P. nalgiovense
penDE gene.