title: Sugar transport systems of Bifidobacterium longum NCC2705.
abstract: Here we present the complement of the carbohydrate uptake systems of the strictly anaerobic probiotic Bifidobacterium longum NCC2705. The genome analysis of this bacterium predicts that it has 19 permeases for the uptake of diverse carbohydrates. The majority belongs to the ATP-binding cassette transporter family with 13 systems identified. Among them are permeases for lactose, maltose, raffinose, and fructooligosaccharides, a commonly used prebiotic additive. We found genes that encode a complete phosphotransferase system (PTS) and genes for three permeases of the major facilitator superfamily. These systems could serve for the import of glucose, galactose, lactose, and sucrose. Growth analysis of NCC2705 cells combined with biochemical characterization and microarray data showed that the predicted substrates are consumed and that the corresponding transport and catabolic genes are expressed. Biochemical analysis of the PTS, in which proteins are central in regulation of carbon metabolism in many bacteria, revealed that B. longum has a glucose-specific PTS, while two other species (Bifidobacterium lactis and Bifidobacterium bifidum) have a fructose-6-phosphate-forming fructose-PTS instead. It became obvious that most carbohydrate systems are closely related to those from other actinomycetes, with a few exceptions. We hope that this report on B. longum carbohydrate transporter systems will serve as a guide for further in-depth analyses on the nutritional lifestyle of this beneficial bacterium.
authors.affiliation: Nestlé Research Center, Vers-chez-les-Blanc, Lausanne, Switzerland.
authors.forename: Stephan
authors.initials: S
authors.lastname: Parche
authors.forename: Johannes
authors.initials: J
authors.lastname: Amon
authors.forename: Ivana
authors.initials: I
authors.lastname: Jankovic
authors.forename: Enea
authors.initials: E
authors.lastname: Rezzonico
authors.forename: Manfred
authors.initials: M
authors.lastname: Beleut
authors.forename: Hande
authors.initials: H
authors.lastname: Barutçu
authors.forename: Inke
authors.initials: I
authors.lastname: Schendel
authors.forename: Mike P
authors.initials: MP
authors.lastname: Eddy
authors.forename: Andreas
authors.initials: A
authors.lastname: Burkovski
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Arigoni
authors.forename: Fritz
authors.initials: F
authors.lastname: Titgemeyer
mesh_terms: D001644:Bifidobacterium / Q000378:metabolism*; D001692:Biological Transport; D050260:Carbohydrate Metabolism; D015964:Gene Expression Regulation, Bacterial; D026901:Membrane Transport Proteins / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D009844:Oligosaccharides / Q000378:metabolism; D010770:Phosphotransferases / Q000378:metabolism*; D011135:Polysaccharides, Bacterial / Q000378:metabolism
chemical_list: D026901:Membrane Transport Proteins; D009844:Oligosaccharides; D011135:Polysaccharides, Bacterial; D010770:Phosphotransferases