title: Cooperative transport between NukFEG and NukH in immunity against the lantibiotic nukacin ISK-1 produced by Staphylococcus warneri ISK-1.
abstract: Nukacin ISK-1 is a lantibiotic produced by Staphylococcus warneri ISK-1. Previous studies have reported that the self-protection system of the nukacin ISK-1 producer involves the cooperative function of the ABC transporter NukFEG and the lantibiotic-binding immunity protein NukH. In this study, the cooperative mechanism between NukFEG and NukH was characterized by using fluorescein-4-isothiocyanate (FITC)-labeled nukacin ISK-1 (FITC-nuk) to clarify the localization of nukacin ISK-1 in the immunity process. Lactococcus lactis recombinants expressing nukFEGH, nukFEG, or nukH showed immunity against FITC-nuk, suggesting that FITC-nuk was recognized by the self-protection system against nukacin ISK-1. Analysis of the interaction between FITC-nuk and energy-deprived cells of the L. lactis recombinants showed that FITC-nuk specifically bound to cells expressing nukH. The interaction between FITC-nuk and nukH-expressing cells was inhibited by the addition of unlabeled nukacin ISK-1 and its derivatives with deletions of the N-terminal tail region, but not by the addition of a synthesized N-terminal tail region. This suggests that the NukH protein recognizes the C-terminal ring region of nukacin ISK-1. The addition of glucose to nukFEGH-expressing cells treated with FITC-nuk resulted in a time-dependent decrease in fluorescence intensity, indicating that FITC-nuk was transported from the cell membrane by the NukFEG protein. These results revealed that after being captured by NukH in an energy-independent manner, nukacin ISK-1 was transported to the extracellular space by NukFEG in an energy-dependent manner.
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Okuda
authors.forename: Yuji
authors.initials: Y
authors.lastname: Aso
authors.forename: Jiro
authors.initials: J
authors.lastname: Nakayama
authors.forename: Kenji
authors.initials: K
authors.lastname: Sonomoto
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000187:drug effects / Q000378:metabolism*; D001426:Bacterial Proteins / Q000187:drug effects / Q000378:metabolism*; D001430:Bacteriocins / Q000378:metabolism*; D001692:Biological Transport; D007700:Kinetics; D007778:Lactobacillus / Q000187:drug effects / Q000378:metabolism; D007934:Leuconostoc / Q000187:drug effects / Q000378:metabolism; D008856:Microscopy, Fluorescence; D013210:Staphylococcus / Q000235:genetics / Q000276:immunology / Q000502:physiology*
chemical_list: D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D001430:Bacteriocins; C421186:nukacin ISK-1