Abstract
In Escherichia coli, elongation factor G (EF-G), a key protein in translational elongation, is particularly susceptible to oxidation. We demonstrated previously that EF-G is inactivated upon formation of an intramolecular disulphide bond. However, the details of the mechanism by which the oxidation of EF-G inhibits the function of EF-G on the ribosome remain to be elucidated. When we oxidized EF-G with hydrogen peroxide, neither the insertion of EF-G into the ribosome nor single-cycle translocation activity in vitro was affected. However, the GTPase activity and the dissociation of EF-G from the ribosome were suppressed when EF-G was oxidized. The synthesis of longer peptides was suppressed to a greater extent than that of a shorter peptide when EF-G was oxidized. Thus, the formation of the disulphide bond in EF-G might interfere with the hydrolysis of GTP that is coupled with dissociation of EF-G from the ribosome and might thereby retard the turnover of EF-G within the translational machinery. When we added thioredoxin to the suppressed translation system that included oxidized EF-G, translational activity was almost immediately restored. We propose that oxidation of EF-G might provide a regulatory mechanism for transient and reversible suppression of translation in E. coli under oxidative stress.
| Original language | English |
|---|---|
| Pages (from-to) | 165-172 |
| Number of pages | 8 |
| Journal | Journal of biochemistry |
| Volume | 158 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 2014 Dec 26 |
| Externally published | Yes |
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Keywords
- EF-G
- GTP hydrolysis
- Oxidative stress
- Protein synthesis
- Redox regulation
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
Cite this
Oxidation of translation factor EF-G transiently retards the translational elongation cycle in Escherichia coli. / Nagano, Takanori; Yutthanasirikul, Rayakorn; Hihara, Yukako; Hisabori, Toru; Kanamori, Takashi; Takeuchi, Nono; Ueda, Takuya; Nishiyama, Yoshitaka.
In: Journal of biochemistry, Vol. 158, No. 2, 26.12.2014, p. 165-172.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Oxidation of translation factor EF-G transiently retards the translational elongation cycle in Escherichia coli
AU - Nagano, Takanori
AU - Yutthanasirikul, Rayakorn
AU - Hihara, Yukako
AU - Hisabori, Toru
AU - Kanamori, Takashi
AU - Takeuchi, Nono
AU - Ueda, Takuya
AU - Nishiyama, Yoshitaka
PY - 2014/12/26
Y1 - 2014/12/26
N2 - In Escherichia coli, elongation factor G (EF-G), a key protein in translational elongation, is particularly susceptible to oxidation. We demonstrated previously that EF-G is inactivated upon formation of an intramolecular disulphide bond. However, the details of the mechanism by which the oxidation of EF-G inhibits the function of EF-G on the ribosome remain to be elucidated. When we oxidized EF-G with hydrogen peroxide, neither the insertion of EF-G into the ribosome nor single-cycle translocation activity in vitro was affected. However, the GTPase activity and the dissociation of EF-G from the ribosome were suppressed when EF-G was oxidized. The synthesis of longer peptides was suppressed to a greater extent than that of a shorter peptide when EF-G was oxidized. Thus, the formation of the disulphide bond in EF-G might interfere with the hydrolysis of GTP that is coupled with dissociation of EF-G from the ribosome and might thereby retard the turnover of EF-G within the translational machinery. When we added thioredoxin to the suppressed translation system that included oxidized EF-G, translational activity was almost immediately restored. We propose that oxidation of EF-G might provide a regulatory mechanism for transient and reversible suppression of translation in E. coli under oxidative stress.
AB - In Escherichia coli, elongation factor G (EF-G), a key protein in translational elongation, is particularly susceptible to oxidation. We demonstrated previously that EF-G is inactivated upon formation of an intramolecular disulphide bond. However, the details of the mechanism by which the oxidation of EF-G inhibits the function of EF-G on the ribosome remain to be elucidated. When we oxidized EF-G with hydrogen peroxide, neither the insertion of EF-G into the ribosome nor single-cycle translocation activity in vitro was affected. However, the GTPase activity and the dissociation of EF-G from the ribosome were suppressed when EF-G was oxidized. The synthesis of longer peptides was suppressed to a greater extent than that of a shorter peptide when EF-G was oxidized. Thus, the formation of the disulphide bond in EF-G might interfere with the hydrolysis of GTP that is coupled with dissociation of EF-G from the ribosome and might thereby retard the turnover of EF-G within the translational machinery. When we added thioredoxin to the suppressed translation system that included oxidized EF-G, translational activity was almost immediately restored. We propose that oxidation of EF-G might provide a regulatory mechanism for transient and reversible suppression of translation in E. coli under oxidative stress.
KW - EF-G
KW - GTP hydrolysis
KW - Oxidative stress
KW - Protein synthesis
KW - Redox regulation
UR - http://www.scopus.com/inward/record.url?scp=84939602522&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84939602522&partnerID=8YFLogxK
U2 - 10.1093/jb/mvv026
DO - 10.1093/jb/mvv026
M3 - Article
VL - 158
SP - 165
EP - 172
JO - Journal of Biochemistry
JF - Journal of Biochemistry
SN - 0021-924X
IS - 2
ER -