Structural Basis for the Function of the β-Barrel Assembly-Enhancing Protease BepA. Issue 3 (1st February 2019)

• Record Type: Journal Article
• Authors: Shahrizal, Mohammad; Daimon, Yasushi; Tanaka, Yoshiki; Hayashi, Yugo; Nakayama, Shintaro; Iwaki, Shigehiro; Narita, Shin-ichiro; Kamikubo, Hironari; Akiyama, Yoshinori; Tsukazaki, Tomoya
• Is Part Of: Journal of molecular biology. Volume 431:Issue 3(2019)
• Page Start: 625
• Page End: 635
• Publication Date: 2019-02-01
• Subjects: outer membrane -- protein biogenesis -- protease -- chaperon -- crystal structure; BAM β-barrel assembly machinery -- TPR tetratricopeptide repeat -- SAXS small-angle X-ray scattering -- EM erythromycin -- PMSF phenylmethanesulfonyl fluoride -- ME 2-mercaptoethanol; Molecular biology -- Periodicals; Biology -- Periodicals; Biochemistry -- Periodicals; Bacteriology -- Periodicals; Molecular Biology -- Periodicals; Biochemistry -- Periodicals; Biologie moléculaire -- Périodiques; Biologie -- Périodiques; Biochimie -- Périodiques; Moleculaire biologie; Biochemistry; Biology; Molecular biology; Periodicals; 572.805
• DOI: 10.1016/j.jmb.2018.11.024
• Languages: English
• ISSNs: 0022-2836

Abstract

Abstract: The β-barrel assembly machinery (BAM) complex mediates the assembly of β-barrel membrane proteins in the outer membrane. BepA, formerly known as YfgC, interacts with the BAM complex and functions as a protease/chaperone for the enhancement of the assembly and/or degradation of β-barrel membrane proteins. To elucidate the molecular mechanism underlying the dual functions of BepA, its full-length three-dimensional structure is needed. Here, we report the crystal structure of full-length BepA at 2.6-Å resolution. BepA possesses an N-terminal protease domain and a C-terminal tetratricopeptide repeat domain, which interact with each other. Domain cross-linking by structure-guided introduction of disulfide bonds did not affect the activities of BepA in vivo, suggesting that the function of this protein does not involve domain rearrangement. The full-length BepA structure is compatible with the previously proposed docking model of BAM complex and tetratricopeptide repeat domain of BepA. Graphical Abstract: Highlights: Crystal structure (2.6 Å) of full-length BepA, β-barrel assembly-enhancing protease BepA Crystal structure represents both its functional and resting states. Functional model of BepA was proposed.