EMD-12735
Cryo-EM map of a Bacillus subtilis MifM-stalled ribosome-nascent chain complex with GMPPNP-SRP bound
EMD-12735
Single-particle2.96 Å
Deposition: 08/04/2021Map released: 02/02/2022
Last modified: 09/03/2022
Sample Organism:
Bacillus subtilis subsp. subtilis str. 168
Sample: SRP-bound MifM-stalled ribosome nascent chain complex
Deposition Authors: Kratzat H
,
Berninghausen O ,
Beckmann R
Sample: SRP-bound MifM-stalled ribosome nascent chain complex
Deposition Authors: Kratzat H
,
Berninghausen O ,
Beckmann R
Inhibition of SRP-dependent protein secretion by the bacterial alarmone (p)ppGpp.
Czech L ,
Mais CN ,
Kratzat H ,
Sarmah P,
Giammarinaro P ,
Freibert SA ,
Esser HF,
Musial J,
Berninghausen O ,
Steinchen W,
Beckmann R ,
Koch HG ,
Bange G
(2022) Nat Commun , 13 , 1069 - 1069
,
Mais CN ,
Kratzat H ,
Sarmah P,
Giammarinaro P ,
Freibert SA ,
Esser HF,
Musial J,
Berninghausen O ,
Steinchen W,
Beckmann R ,
Koch HG ,
Bange G
(2022) Nat Commun , 13 , 1069 - 1069
Abstract:
The stringent response enables bacteria to respond to nutrient limitation and other stress conditions through production of the nucleotide-based second messengers ppGpp and pppGpp, collectively known as (p)ppGpp. Here, we report that (p)ppGpp inhibits the signal recognition particle (SRP)-dependent protein targeting pathway, which is essential for membrane protein biogenesis and protein secretion. More specifically, (p)ppGpp binds to the SRP GTPases Ffh and FtsY, and inhibits the formation of the SRP receptor-targeting complex, which is central for the coordinated binding of the translating ribosome to the SecYEG translocon. Cryo-EM analysis of SRP bound to translating ribosomes suggests that (p)ppGpp may induce a distinct conformational stabilization of the NG domain of Ffh and FtsY in Bacillus subtilis but not in E. coli.
The stringent response enables bacteria to respond to nutrient limitation and other stress conditions through production of the nucleotide-based second messengers ppGpp and pppGpp, collectively known as (p)ppGpp. Here, we report that (p)ppGpp inhibits the signal recognition particle (SRP)-dependent protein targeting pathway, which is essential for membrane protein biogenesis and protein secretion. More specifically, (p)ppGpp binds to the SRP GTPases Ffh and FtsY, and inhibits the formation of the SRP receptor-targeting complex, which is central for the coordinated binding of the translating ribosome to the SecYEG translocon. Cryo-EM analysis of SRP bound to translating ribosomes suggests that (p)ppGpp may induce a distinct conformational stabilization of the NG domain of Ffh and FtsY in Bacillus subtilis but not in E. coli.