PDBsum entry 5l3v

Protein transport

PDB id: 5l3v

Contents

Protein chains

291 a.a.

Ligands

GDP ×2

SO4 ×3

Waters ×178

PDB id:

5l3v

Name:

Protein transport

Title:

Structure of the crenarchaeal srp54 gtpase bound to gdp

Structure:

Signal recognition particle 54 kda protein. Chain: a, b. Synonym: srp54. Engineered: yes

Source:

Sulfolobus solfataricus. Organism_taxid: 2287. Gene: srp54, sso0971. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

2.30Å R-factor: 0.178 R-free: 0.222

Authors:

G.Bange,K.Wild,I.Sinning

Key ref:

K.Wild et al. (2016). Structural Basis for Conserved Regulation and Adaptation of the Signal Recognition Particle Targeting Complex. J Mol Biol, 428, 2880-2897. PubMed id: 27241309 DOI: 10.1016/j.jmb.2016.05.015

Date:

24-May-16 Release date: 08-Jun-16

Protein chains

Q97ZE7  (SRP54_SULSO) -  Signal recognition particle 54 kDa protein from Saccharolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2)

Seq: 447 a.a.

Struc: 291 a.a.

Enzyme reactions

• Enzyme class: E.C.3.6.5.4 - signal-recognition-particle GTPase.
• Reaction: GTP + H2O = GDP + phosphate + H⁺

GTP + H2O = GDP (Bound ligand (Het Group name = GDP) corresponds exactly) + phosphate + H(+)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

DOI no: 10.1016/j.jmb.2016.05.015

J Mol Biol 428:2880-2897 (2016)

PubMed id: 27241309

Structural Basis for Conserved Regulation and Adaptation of the Signal Recognition Particle Targeting Complex.

K.Wild, G.Bange, D.Motiejunas, J.Kribelbauer, A.Hendricks, B.Segnitz, R.C.Wade, I.Sinning.

ABSTRACT

The signal recognition particle (SRP) is a ribonucleoprotein complex with a key role in targeting and insertion of membrane proteins. The two SRP GTPases, SRP54 (Ffh in bacteria) and FtsY (SRα in eukaryotes), form the core of the targeting complex (TC) regulating the SRP cycle. The architecture of the TC and its stimulation by RNA has been described for the bacterial SRP system while this information is lacking for other domains of life. Here, we present the crystal structures of the GTPase heterodimers of archaeal (Sulfolobus solfataricus), eukaryotic (Homo sapiens), and chloroplast (Arabidopsis thaliana) SRP systems. The comprehensive structural comparison combined with Brownian dynamics simulations of TC formation allows for the description of the general blueprint and of specific adaptations of the quasi-symmetric heterodimer. Our work defines conserved external nucleotide-binding sites for SRP GTPase activation by RNA. Structural analyses of the GDP-bound, post-hydrolysis states reveal a conserved, magnesium-sensitive switch within the I-box. Overall, we provide a general model for SRP cycle regulation by RNA.