Crystal Structure of the Salmonella Typhimurium Effector GtgE.

Salmonella Typhimurium GtgE is an effector protein contributing to the virulence of this pathogen. It was shown to possess highly selective proteolytic activity against a subset of Rab proteins that helps in evasion of Salmonella-containing vacuole (SCV) fusion with lysosomes. Cys45, His151 and Asp1...

Full description

Bibliographic Details
Main Authors: Caishuang Xu, Guennadi Kozlov, Kathy Wong, Kalle Gehring, Miroslaw Cygler
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2016-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC5140068?pdf=render
_version_ 1811208810817126400
author Caishuang Xu
Guennadi Kozlov
Kathy Wong
Kalle Gehring
Miroslaw Cygler
author_facet Caishuang Xu
Guennadi Kozlov
Kathy Wong
Kalle Gehring
Miroslaw Cygler
author_sort Caishuang Xu
collection DOAJ
description Salmonella Typhimurium GtgE is an effector protein contributing to the virulence of this pathogen. It was shown to possess highly selective proteolytic activity against a subset of Rab proteins that helps in evasion of Salmonella-containing vacuole (SCV) fusion with lysosomes. Cys45, His151 and Asp169 are essential for proteolytic activity. The structure of a C-terminal fragment GtgE(79-214) indicated the presence of a papain-like fold. Here, we present the structure of GtgE(17-214) containing the fully assembled active site. The design of a proteolytically active and crystallizable GtgE construct was aided by NMR spectroscopy. The protein indeed displays papain-like fold with an assembled Cys-His-Asp catalytic triad. Like the full-length GtgE, the crystallizable construct showed low activity in vitro for its known substrates, Rab32 and Rab29. NMR titration experiments showed at most very weak binding of GtgE to the peptide encompassing the Rab29 cleavage site. In view of the low in vitro activity and poor substrate binding, we postulate that the function of GtgE in vivo as a proteolytic enzyme is dependent on other factor(s), such as a protein partner or interactions with the SCV membrane, which stimulate(s) GtgE activity in vivo.
first_indexed 2024-04-12T04:27:48Z
format Article
id doaj.art-8a18386c49084101897ab2d629267d0a
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-04-12T04:27:48Z
publishDate 2016-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-8a18386c49084101897ab2d629267d0a2022-12-22T03:48:01ZengPublic Library of Science (PLoS)PLoS ONE1932-62032016-01-011112e016664310.1371/journal.pone.0166643Crystal Structure of the Salmonella Typhimurium Effector GtgE.Caishuang XuGuennadi KozlovKathy WongKalle GehringMiroslaw CyglerSalmonella Typhimurium GtgE is an effector protein contributing to the virulence of this pathogen. It was shown to possess highly selective proteolytic activity against a subset of Rab proteins that helps in evasion of Salmonella-containing vacuole (SCV) fusion with lysosomes. Cys45, His151 and Asp169 are essential for proteolytic activity. The structure of a C-terminal fragment GtgE(79-214) indicated the presence of a papain-like fold. Here, we present the structure of GtgE(17-214) containing the fully assembled active site. The design of a proteolytically active and crystallizable GtgE construct was aided by NMR spectroscopy. The protein indeed displays papain-like fold with an assembled Cys-His-Asp catalytic triad. Like the full-length GtgE, the crystallizable construct showed low activity in vitro for its known substrates, Rab32 and Rab29. NMR titration experiments showed at most very weak binding of GtgE to the peptide encompassing the Rab29 cleavage site. In view of the low in vitro activity and poor substrate binding, we postulate that the function of GtgE in vivo as a proteolytic enzyme is dependent on other factor(s), such as a protein partner or interactions with the SCV membrane, which stimulate(s) GtgE activity in vivo.http://europepmc.org/articles/PMC5140068?pdf=render
spellingShingle Caishuang Xu
Guennadi Kozlov
Kathy Wong
Kalle Gehring
Miroslaw Cygler
Crystal Structure of the Salmonella Typhimurium Effector GtgE.
PLoS ONE
title Crystal Structure of the Salmonella Typhimurium Effector GtgE.
title_full Crystal Structure of the Salmonella Typhimurium Effector GtgE.
title_fullStr Crystal Structure of the Salmonella Typhimurium Effector GtgE.
title_full_unstemmed Crystal Structure of the Salmonella Typhimurium Effector GtgE.
title_short Crystal Structure of the Salmonella Typhimurium Effector GtgE.
title_sort crystal structure of the salmonella typhimurium effector gtge
url http://europepmc.org/articles/PMC5140068?pdf=render
work_keys_str_mv AT caishuangxu crystalstructureofthesalmonellatyphimuriumeffectorgtge
AT guennadikozlov crystalstructureofthesalmonellatyphimuriumeffectorgtge
AT kathywong crystalstructureofthesalmonellatyphimuriumeffectorgtge
AT kallegehring crystalstructureofthesalmonellatyphimuriumeffectorgtge
AT miroslawcygler crystalstructureofthesalmonellatyphimuriumeffectorgtge