ISSN:
1432-072X
Keywords:
Cytophaga johnsonae
;
Glucose uptake
;
Substrate specificity
;
Substrate affinity
;
Chemostat operation
;
Facultative oligotrophy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The influence of different physiological states on the glucose uptake and mineralization by Cytophaga johnsonae, a freshwater isolate, was examined in batch and chemostat cultures. At different growth rates under glucose limitation in chemostat cultures, different uptake patterns for 14C labeled glucose were observed. In batch culture and at high growth rates the glucose uptake potential showed a higher maximum velocity and a much lower substrate affinity than at lower growth rates. These findings and the results of short-term labeling patterns could be explained by two different glucose uptake mechanisms which enable the strain to grow efficiently both at high and low substrate concentrations. Substrate specificity studies showed that a structural change of the C-2 atom of the glucose molecule was tolerated by both systems. The consequences of these results for the ecophysiological classification of the Cytophaga group and for the operation of continuous cultures are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00521292
Permalink