6i56

Publication Abstract from PubMed

As part of the Virus-X Consortium that aims to identify and characterize novel proteins and enzymes from bacteriophages and archaeal viruses, the genes of the putative lytic proteins XepA from Bacillus subtilis prophage PBSX and YomS from prophage SPbeta were cloned and the proteins were subsequently produced and functionally characterized. In order to elucidate the role and the molecular mechanism of XepA and YomS, the crystal structures of these proteins were solved at resolutions of 1.9 and 1.3 A, respectively. XepA consists of two antiparallel beta-sandwich domains connected by a 30-amino-acid linker region. A pentamer of this protein adopts a unique dumbbell-shaped architecture consisting of two discs and a central tunnel. YomS (12.9 kDa per monomer), which is less than half the size of XepA (30.3 kDa), shows homology to the C-terminal part of XepA and exhibits a similar pentameric disc arrangement. Each beta-sandwich entity resembles the fold of typical cytoplasmic membrane-binding C2 domains. Only XepA exhibits distinct cytotoxic activity in vivo, suggesting that the N-terminal pentameric domain is essential for this biological activity. The biological and structural data presented here suggest that XepA disrupts the proton motive force of the cytoplasmatic membrane, thus supporting cell lysis.

Crystal structures of the Bacillus subtilis prophage lytic cassette proteins XepA and YomS.,Freitag-Pohl S, Jasilionis A, Hakansson M, Svensson LA, Kovacic R, Welin M, Watzlawick H, Wang L, Altenbuchner J, Plotka M, Kaczorowska AK, Kaczorowski T, Nordberg Karlsson E, Al-Karadaghi S, Walse B, Aevarsson A, Pohl E Acta Crystallogr D Struct Biol. 2019 Nov 1;75(Pt 11):1028-1039. doi:, 10.1107/S2059798319013330. Epub 2019 Nov 1. PMID:31692476^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.