Structural outline of the detailed mechanism for elongation factor Ts-mediated guanine nucleotide exchange on elongation factor Tu

TY - JOUR

T1 - Structural outline of the detailed mechanism for elongation factor Ts-mediated guanine nucleotide exchange on elongation factor Tu

AU - Thirup, Søren Skou

AU - Van, Lan Bich

AU - Nielsen, Tine K

AU - Knudsen, Charlotte R

N1 - Copyright © 2015. Published by Elsevier Inc.

PY - 2015/6/11

Y1 - 2015/6/11

N2 - Translation elongation factor EF-Tu belongs to the superfamily of guanine-nucleotide binding proteins, which play key cellular roles as regulatory switches. All G-proteins require activation via exchange of GDP for GTP to carry out their respective tasks. Often, guanine-nucleotide exchange factors are essential to this process. During translation, EF-Tu:GTP transports aminoacylated tRNA to the ribosome. GTP is hydrolyzed during this process, and subsequent reactivation of EF-Tu is catalyzed by EF-Ts. The reaction path of guanine-nucleotide exchange is structurally poorly defined for EF-Tu and EF-Ts. We have determined the crystal structures of the following reaction intermediates: two structures of EF-Tu:GDP:EF-Ts (2.2 and 1.8 Å resolution), EF-Tu:PO4:EF-Ts (1.9 Å resolution), EF-Tu:GDPNP:EF-Ts (2.2 Å resolution) and EF-Tu:GDPNP:pulvomycin:Mg(2+):EF-Ts (3.5 Å resolution). These structures provide snapshots throughout the entire exchange reaction and suggest a mechanism for the release of EF-Tu in its GTP conformation. An inferred sequence of events during the exchange reaction is presented.

AB - Translation elongation factor EF-Tu belongs to the superfamily of guanine-nucleotide binding proteins, which play key cellular roles as regulatory switches. All G-proteins require activation via exchange of GDP for GTP to carry out their respective tasks. Often, guanine-nucleotide exchange factors are essential to this process. During translation, EF-Tu:GTP transports aminoacylated tRNA to the ribosome. GTP is hydrolyzed during this process, and subsequent reactivation of EF-Tu is catalyzed by EF-Ts. The reaction path of guanine-nucleotide exchange is structurally poorly defined for EF-Tu and EF-Ts. We have determined the crystal structures of the following reaction intermediates: two structures of EF-Tu:GDP:EF-Ts (2.2 and 1.8 Å resolution), EF-Tu:PO4:EF-Ts (1.9 Å resolution), EF-Tu:GDPNP:EF-Ts (2.2 Å resolution) and EF-Tu:GDPNP:pulvomycin:Mg(2+):EF-Ts (3.5 Å resolution). These structures provide snapshots throughout the entire exchange reaction and suggest a mechanism for the release of EF-Tu in its GTP conformation. An inferred sequence of events during the exchange reaction is presented.

U2 - 10.1016/j.jsb.2015.06.011

DO - 10.1016/j.jsb.2015.06.011

M3 - Journal article

C2 - 26073967

SN - 1047-8477

VL - 191

SP - 10

EP - 21

JO - Journal of Structural Biology

JF - Journal of Structural Biology

IS - 1

ER -