E. Gelhaye et al., ADHESION AND GROWTH-RATE OF CLOSTRIDIUM-CELLULOLYTICUM ATCC-35319 ON CRYSTALLINE CELLULOSE, Journal of bacteriology, 175(11), 1993, pp. 3452-3458
The rate of tritiated-thymidine incorporation into DNA was used to est
imate Clostridium cellulolyticum H10 growth rates on Avicel cellulose,
taking into consideration both the unattached cells and the cells adh
ered to the substrate. The generation time on cellobiose calculated fr
om the data on cell density (4.5 h) agreed well with the generation ti
me calculated by tritiated-thymidine incorporation (3.8 h). Growth on
Avicel cellulose occurred when bacteria were adhered to their substrat
e; 80% of the biomass was detected on the cellulose. Taking into consi
deration attached and free bacteria, the generation time as determined
by thymidine incorporation was about 8 h, whereas by bacterial-protei
n estimation it was about 13 h. In addition to the growth rate of the
bacteria on the cellulose, the release of adhered cells constituted an
important factor in the efficiency of the cellulolysis. The stage of
growth influenced adhesion of C cellulolyticum; maximum adhesion was f
ound during the exponential phase. Under the conditions used, the end
of growth was characterized by an acute release of biomass and cellula
se activity from the cellulose. An exhaustion of the accessible cellul
ose could be responsible for this release.