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The glycolytic pathway of the enteric pathogen Campylobacter jejuni is incomplete; the absence of phosphofructokinase means that the suppression of futile cycling at this point in the glycolytic--gluconeogenic pathway might not be required, and therefore the mechanism for controlling pathway flux is likely to be quite different or absent. In this study, the characteristics of fructose-1,6-bisphosphatase (FBPase) of C. jejuni are described and the regulation of this enzyme is compared with the equivalent enzymes from organisms capable of glycolysis. The enzyme is insensitive to AMP inhibition, unlike other type I FBPases. Campylobacter jejuni FBPase also shows limited sensitivity to other glycolytic and gluconeogenic intermediates. The allosteric cooperative control of the enzyme's activity found in type I FBPases appears to have been lost. Key words: Campylobacter jejuni, glycolysis, gluconeogenesis, metabolic control, fructose-1,6-bisphosphatase. La voie glycolytique de l'agent pathogene enterique Campylobacter jejuni est incomplete; l'absence de phosphofructokinase signifie que la suppression du cycle futile a cette etape de la voie glycolyse--gluconeogenese pourrait ne pas etre necessaire et qu'en consequence, le mecanisme de controle du flux de la voie est probablement tres different ou absent. Dans cette etude, les caracteristiques de la fructose-1,6-bisphosphatase (FBPase) de C. jejuni sont decrites et la regulation de cette enzyme est comparee a celle d'enzymes equivalentes d'organismes capables de realiser la glycolyse. L'enzyme est insensible a l'inhibition par l'AMP, contrairement aux autres FBPases de type I. La FBPase de C. jejuni montre aussi une sensibilite limitee envers d'autres intermediaires de la glycolyse et de la gluconeogenese. Le controle cooperatif allosterique de l'activite de l'enzyme trouve chez les FBPases de type I semble aussi avoir ete perdu. [Traduit par la Redaction] Mots-cles: Campylobacter jejuni, glycolyse, gluconeogenese, controle metabolique, fructose-1,6-bisphosphatase., Introduction Campylobacter jejuni is an enteric pathogen that has emerged as one of the most common causes of bacterial gastroenteritis and a major public health concern in the developed world [...]