TY - JOUR T1 - Mechanistic aspects of maltotriose-conjugate translocation to the Gram-negative bacteria cytoplasm JF - Life Science Alliance JO - Life Sci. Alliance DO - 10.26508/lsa.201800242 VL - 2 IS - 1 SP - e201800242 AU - Estelle Dumont AU - Julia Vergalli AU - Jelena Pajovic AU - Satya P Bhamidimarri AU - Koldo Morante AU - Jiajun Wang AU - Dmitrijs Lubriks AU - Edgars Suna AU - Robert A Stavenger AU - Mathias Winterhalter AU - Matthieu Réfrégiers AU - Jean-Marie Pagès Y1 - 2019/02/01 UR - https://www.life-science-alliance.org/content/2/1/e201800242.abstract N2 - Small molecule accumulation in Gram-negative bacteria is a key challenge to discover novel antibiotics, because of their two membranes and efflux pumps expelling toxic molecules. An approach to overcome this challenge is to hijack uptake pathways so that bacterial transporters shuttle the antibiotic to the cytoplasm. Here, we have characterized maltodextrin–fluorophore conjugates that can pass through both the outer and inner membranes mediated by components of the Escherichia coli maltose regulon. Single-channel electrophysiology recording demonstrated that the compounds permeate across the LamB channel leading to accumulation in the periplasm. We have also demonstrated that a maltotriose conjugate distributes into both the periplasm and cytoplasm. In the cytoplasm, the molecule activates the maltose regulon and triggers the expression of maltose binding protein in the periplasmic space indicating that the complete maltose entry pathway is induced. This maltotriose conjugate can (i) reach the periplasmic and cytoplasmic compartments to significant internal concentrations and (ii) auto-induce its own entry pathway via the activation of the maltose regulon, representing an interesting prototype to deliver molecules to the cytoplasm of Gram-negative bacteria. ER -