Benzoate degradation via the ortho pathway in Alcaligenes eutrophus is perturbed by succinate.
During batch growth of Alcaligenes eutrophus on benzoate-plus-succinate mixtures, substrates were simultaneously metabolized, leading to a higher specific growth rate (mu = 0.56 h-1) than when a single substrate was used (mu = 0.51 h-1 for benzoate alone and 0.44 h-1 for succinate alone), without adversely affecting the growth yield (0.57 Cmol/Cmol). Flux distribution analysis revealed that succinate dehydrogenase most probably controls the rate of total succinate consumption (the maximum flux being 9.7 mmol.g-1.h-1). It is postulated that the relative consumption rate of each substrate is in part related to modified levels of gene expression but to a large extent is dependent upon the presence of succinate, end product of the beta-ketoadipate pathway. Indeed, the in vitro beta-ketoadipate-succinyl coenzyme A transferase activity was seen to be inhibited by succinate, a coproduct of the reaction.
Ampe
F
F
Centre de Bioingénierie Gilbert Durand, Institut National des Sciences Appliquées, Unité Mixte de Recherche CNRS 5044, Toulouse, France. ampe;lindley@insa-tlsc.fr
Uribelarrea
J L
JL
Aragao
G M
GM
Lindley
N D
ND
D000272:Adipates / Q000378:metabolism; D000421:Alcaligenes / Q000254:growth & development / Q000378:metabolism*; D001565:Benzoates / Q000037:antagonists & inhibitors / Q000378:metabolism*; D003065:Coenzyme A / Q000378:metabolism; D003470:Culture Media / Q000378:metabolism; D007700:Kinetics; D013385:Succinate Dehydrogenase / Q000378:metabolism; D013386:Succinates / Q000378:metabolism*; D019802:Succinic Acid
D000272:Adipates; D001565:Benzoates; D003470:Culture Media; D013386:Succinates; C027316:3-oxoadipic acid; D019802:Succinic Acid; D013385:Succinate Dehydrogenase; D003065:Coenzyme A