ジャーナル: J Biol Chem / 年: 2016 タイトル: Crystal Structure of the CTP1L Endolysin Reveals How Its Activity Is Regulated by a Secondary Translation Product. 著者: Matthew Dunne / Stefan Leicht / Boris Krichel / Haydyn D T Mertens / Andrew Thompson / Jeroen Krijgsveld / Dmitri I Svergun / Natalia Gómez-Torres / Sonia Garde / Charlotte Uetrecht / Arjan ...著者: Matthew Dunne / Stefan Leicht / Boris Krichel / Haydyn D T Mertens / Andrew Thompson / Jeroen Krijgsveld / Dmitri I Svergun / Natalia Gómez-Torres / Sonia Garde / Charlotte Uetrecht / Arjan Narbad / Melinda J Mayer / Rob Meijers / 要旨: Bacteriophages produce endolysins, which lyse the bacterial host cell to release newly produced virions. The timing of lysis is regulated and is thought to involve the activation of a molecular ...Bacteriophages produce endolysins, which lyse the bacterial host cell to release newly produced virions. The timing of lysis is regulated and is thought to involve the activation of a molecular switch. We present a crystal structure of the activated endolysin CTP1L that targets Clostridium tyrobutyricum, consisting of a complex between the full-length protein and an N-terminally truncated C-terminal cell wall binding domain (CBD). The truncated CBD is produced through an internal translation start site within the endolysin gene. Mutants affecting the internal translation site change the oligomeric state of the endolysin and reduce lytic activity. The activity can be modulated by reconstitution of the full-length endolysin-CBD complex with free CBD. The same oligomerization mechanism applies to the CD27L endolysin that targets Clostridium difficile and the CS74L endolysin that targets Clostridium sporogenes. When the CTP1L endolysin gene is introduced into the commensal bacterium Lactococcus lactis, the truncated CBD is also produced, showing that the alternative start codon can be used in other bacterial species. The identification of a translational switch affecting oligomerization presented here has implications for the design of effective endolysins for the treatment of bacterial infections.
SHEET DETERMINATION METHOD: DSSP THE SHEETS PRESENTED AS "AA" IN EACH CHAIN ON SHEET RECORDS BELOW ... SHEET DETERMINATION METHOD: DSSP THE SHEETS PRESENTED AS "AA" IN EACH CHAIN ON SHEET RECORDS BELOW IS ACTUALLY AN 8-STRANDED BARREL THIS IS REPRESENTED BY A 9-STRANDED SHEET IN WHICH THE FIRST AND LAST STRANDS ARE IDENTICAL.
THIS CHAIN IS A TRUNCATED CELL WALL BINDING DOMAIN THAT IS THE RESULT OF SECONDARY TRANSLATION ...THIS CHAIN IS A TRUNCATED CELL WALL BINDING DOMAIN THAT IS THE RESULT OF SECONDARY TRANSLATION WITHIN THE ENDOLYSIN GENE. THE VAL195 IS REPLACED BY A METHIONINE
解像度: 1.9→19.9 Å / Cor.coef. Fo:Fc: 0.963 / Cor.coef. Fo:Fc free: 0.943 / SU B: 2.55 / SU ML: 0.075 / 交差検証法: THROUGHOUT / ESU R: 0.11 / ESU R Free: 0.114 / 立体化学のターゲット値: MAXIMUM LIKELIHOOD / 詳細: HYDROGENS HAVE BEEN ADDED IN THE RIDING POSITIONS.
Rfactor
反射数
%反射
Selection details
Rfree
0.20468
2132
5 %
RANDOM
Rwork
0.16196
-
-
-
obs
0.16412
40146
99.87 %
-
溶媒の処理
イオンプローブ半径: 0.8 Å / 減衰半径: 0.8 Å / VDWプローブ半径: 1.2 Å / 溶媒モデル: MASK