Glucose Metabolism via the Entner-Doudoroff Pathway inCampylobacter: A Rare Trait that Enhances Survival and Promotes Biofilm Formation in Some Isolates.
Vegge CS., Jansen van Rensburg MJ., Rasmussen JJ., Maiden MCJ., Johnsen LG., Danielsen M., MacIntyre S., Ingmer H., Kelly DJ.
Isolates of the zoonotic pathogenCampylobacterare generally considered to be unable to metabolize glucose due to lack of key glycolytic enzymes. However, the Entner-Doudoroff (ED) pathway has been identified inCampylobacter jejunisubsp.doyleiand a fewC. coliisolates. A systematic search for ED pathway genes in a wide range ofCampylobacterisolates and in theC. jejuni/coliPubMLST database revealed that 1.7% of >6,000 genomes encoded a complete ED pathway, including bothC. jejuniandC. colifrom diverse clinical, environmental and animal sources. In rich media, glucose significantly enhanced stationary phase survival of a set of ED-positiveC. coliisolates. Unexpectedly, glucose massively promoted floating biofilm formation in some of these ED-positive isolates. Metabolic profiling by gas chromatography-mass spectrometry revealed distinct responses to glucose in a low biofilm strain (CV1257) compared to a high biofilm strain (B13117), consistent with preferential diversion of hexose-6-phosphate to polysaccharide in B13117. We conclude that while the ED pathway is rare amongstCampylobacterisolates causing human disease (the majority of which would be of agricultural origin), some glucose-utilizing isolates exhibit specific fitness advantages, including stationary-phase survival and biofilm production, highlighting key physiological benefits of this pathway in addition to energy conservation.