Pathways of D-fructose and D-glucose catabolism in marine species of Alcaligenes, Pseudomonas marina, and Alteromonas communis.
Cell-free extracts of D-fructose grown cells of marine species of Alcaligenes as well as Pseudomonas marina contained an activity which catalyzed a P-enolpyruvate-dependent phosphorylation of D-fructose in the 1-position as well as activities of the following enzymes: 1-P-fructokinase, fructose-1,6-P2 aldolase, PPi-dependent 6-P-fructokinase, fructokinase, glucokinase, P-hexose isomerase, glucose-6-P dehydrogenase, 6-P-gluconate dehydrase, and 2-keto-3-deoxy-6-P-gluconate aldolase. The presence of these enzyme activites would allow D-fructose to be degraded by the Embden-Meyerhof pathway and/or the Entner-Doudoroff pathway. In cell-free extracts of D-glucose grown cells, the activity catalyzing a P-enolpyruvate-dependent phosphorylation of D-fructose as well as 1-P-fructokinase activity were reduced or absent while the remaining enzymes were present at levels similar to those found in D-fructose grown cells. Radiolabeling experiments suggested that both D-fructose and D-glucose were utilized primarily via the Entner-Doudoroff pathway. Alteromonas communis, a marine species lacking 1-P-fructokinase and the PPi-dependent 6-P-fructokinase, contained all the enzyme activites necessary for the catabolism of D-fructose and D-glucose by the Entner-Doudoroff pathway; the involvement of this pathway was also consitent with the results of the radiolabeling experiments.
D000421:Alcaligenes / Q000201:enzymology; D005632:Fructose / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D006088:Gram-Negative Aerobic Bacteria / Q000201:enzymology*; D010732:Phosphofructokinase-1 / Q000032:analysis; D011549:Pseudomonas / Q000201:enzymology; D014871:Water Microbiology
D005632:Fructose; D010732:Phosphofructokinase-1; D005947:Glucose