ISSN:
1432-072X
Keywords:
Rhizobium leguminosarum
;
Catabolic enzymes
;
Bacteroids
;
Percoll gradients
;
Chemostats
;
Substrate consumption
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Bacteroids of R. leguminosarum MNF3841 isolated from pea nodules using Percoll gradients had activities of TCA cycle enzymes up to 6-fold higher than those measured in free-living cells grown on fumarate or sucrose. Activities of sugar catabolic enzymes on the other hand were 2–14-fold lower in isolated bacteroids than in sucrose-grown free-living cells. In continuous culture, cells of strain MNF3841 grown on sucrose under P i limitation had 2–3-fold higher activities of invertase, glucose-6-phosphate dehydrogenase, the Entner-Doudoroff enzymes and 6-phosphogluconate dehydrogenase, than cells grown on fumarate. With one exception O2 limited cultures had similar activities of the carbon catabolic enzymes to P i-limited cultures grown in the same substrate. Glucose-6-phosphate dehydrogenase in O2-limited cells grown of fumarate was 50% lower than in P i-limited cells. Co-utilization of fumarate and sucrose occurred with chemostat cultures supplied with both under a variety of conditions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00425495
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