Further experimentation verified the relationship between
the chained long rod morphotype and biofilm formation in
the H1206(pJAM1020) strain. A culture of planktonic cells
with an average length of 1.6 μm underwent a morphological
shift during the first 12 h of biofilm formation in
replicate chamber slide wells (Figure 3E). The difference
in length between populations of 2,000 planktonic and
2,000 biofilm cells was statistically significant (P < 0.0001 in
unpaired t test). Cellular structures within biofilms were on
average greater than twice as long, were more variable in
size (with a standard deviation in length of 3.1 μm) and
reached a maximum length ten times greater than that
measured within the planktonic culture from which the
biofilm was derived (Figure 3E).