title: Functional characterization of a microbial aquaglyceroporin.
abstract: The major intrinsic proteins (MIPs) constitute a widespread membrane channel family essential for osmotic cell equilibrium. The MIPs can be classified into three functional subgroups: aquaporins, glycerol facilitators and aquaglyceroporins. Bacterial MIP genes have been identified in archaea as well as in Gram-positive and Gram-negative eubacteria. However, with the exception of Escherichia coli, most bacterial MIPs have been analysed by sequence homology. Since no MIP has yet been functionally characterized in Gram-positive bacteria, we have studied one of these members from Lactococcus lactis. This MIP is shown to be permeable to glycerol, like E. coli GlpF, and to water, like E. coli AqpZ. This is the first characterization of a microbial MIP that has a mixed function. This result provides important insights to reconstruct the evolutionary history of the MIP family and to elucidate the molecular pathway of water and other solutes in these channels.
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Alexandrine
authors.initials: A
authors.lastname: Froger
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Rolland
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Patrick
authors.initials: P
authors.lastname: Bron
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Valérie
authors.initials: V
authors.lastname: Lagrée
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Françoise Le
authors.initials: FL
authors.lastname: Cahérec
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Deschamps
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Hubert
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Pellerin
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Daniel
authors.initials: D
authors.lastname: Thomas
authors.affiliation: UMR CNRS, Interactions Cellulaires et Moléculaires, Equipe Canaux et Récepteurs Membranaires, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex, France1.
authors.forename: Christian
authors.initials: C
authors.lastname: Delamarche
mesh_terms: D000818:Animals; D020346:Aquaporins / Q000378:metabolism*; D001692:Biological Transport; D020285:Cryoelectron Microscopy; D004926:Escherichia coli / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D066298:In Vitro Techniques; D013294:Lactococcus lactis / Q000378:metabolism* / Q000648:ultrastructure; D008562:Membrane Glycoproteins / Q000378:metabolism*; D009865:Oocytes / Q000378:metabolism; D016415:Sequence Alignment; D014867:Water / Q000378:metabolism; D014982:Xenopus laevis
chemical_list: D020346:Aquaporins; D008562:Membrane Glycoproteins; D014867:Water; D005990:Glycerol