The topic of this years' osbach Colloquium was DNA integration. We have
tried to bring together experts from different fields of research who
are studying natural processes by which DNA molecules from differ- ent
sources are linked. It has been known for a long time that such linkage
occurs between the chromosomes of bacteriophages and plasmids on the one
hand and the chromosome of the bacterial host on the other. This process
has been especially well studied in bacteriophage A. Since it is
controlled in a complicated way, we began with a lecture by M. ptashne
on these regulatory processes. H. Nash described the inte- gration of
bacteriophage A into the bacterial chromosome. To put this site-specific
process into perspective, G. Mosig lectured on genetic recombination in
prokaryotes in general and K. Murray described the use of bacteriophage
A as an artificial vector for genetic engineering. A different kind of
bacteriophage integration is shown by bacteriophage Mu, which is much
less specific in its choice of an integration site than A. The
properties of this phage were described by P. van de Putte.