title: Crystal structure and specific binding mode of sisomicin to the bacterial ribosomal decoding site.
abstract: Sisomicin with an unsaturated sugar ring I displays better antibacterial activity than other structurally related aminoglycosides, such as gentamicin, tobramycin, and amikacin. In the present study, we have confirmed by X-ray analyses that the binding mode of sisomicin is basically similar but not identical to that of the related compounds having saturated ring I. A remarkable difference is found in the stacking interaction between ring I and G1491. While the typical saturated ring I with a chair conformation stacks on G1491 through CH/π interactions, the unsaturated ring I of sisomicin with a partially planar conformation can share its π-electron density with G1491 and fits well within the A-site helix.
authors.affiliation: Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University , 7-1 Kioi-cho, Chiyoda-ku, 102-8554 Tokyo, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Kondo
authors.affiliation: Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University , 7-1 Kioi-cho, Chiyoda-ku, 102-8554 Tokyo, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Koganei
authors.affiliation: Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University , 7-1 Kioi-cho, Chiyoda-ku, 102-8554 Tokyo, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Kasahara
keywords: X-ray analysis; aminoglycoside; decoding; ribosome; stacking interaction