This result implies that
the cellulose-synthesising genes and enzymes, as well as
other metabolic and replication machinery of the organism,
were not noticeably a¡ected by the insertion. Further,
the insertion of the lacZ gene enabled the modi¢ed strain
to produce signi¢cantly higher amounts of cellulose with
lactose as a source of carbon. This was the major factor,
which predisposes the mutant strain’s ability to grow and
produce cellulose with lactose as the carbon source. At
this point, it should be emphasised that the ability of the
modi¢ed strain, ITz3, to grow in lactose with the corresponding