SAXSdb — 2xxa

▼

1. Protein Identity and Related Structures Protein Identity & Related Structures

SIGNAL RECOGNITION PARTICLE PROTEIN

ESCHERICHIA COLI K-12

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein–RNA	Heteromer	Protein 2 RNA 1	SRP RECEPTOR FTSY × 1 （P10121） 4.5S RNA × 1 PHOSPHOMETHYLPHOSPHONIC ACID GUANYLATE ESTER × 2 MAGNESIUM ION × 2 water × 2	Consistent with all polymers
2	Protein–RNA	Heteromer	Protein 2 RNA 1	SRP RECEPTOR FTSY × 1 （P10121） 4.5S RNA × 1 PHOSPHOMETHYLPHOSPHONIC ACID GUANYLATE ESTER × 2 MAGNESIUM ION × 2 water × 2	Consistent with all polymers

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	SRP54_ECOLI
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 1–433； UniProt 1–433 Author chain C； PDBConstruct 1–433； UniProt 1–433

SRP RECEPTOR FTSY

ESCHERICHIA COLI K-12

UniProt P10121

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein–RNA	Heteromer	Protein 2 RNA 1	SIGNAL RECOGNITION PARTICLE PROTEIN × 1 （P0AGD7） 4.5S RNA × 1 PHOSPHOMETHYLPHOSPHONIC ACID GUANYLATE ESTER × 2 MAGNESIUM ION × 2 water × 2	Consistent with all polymers
2	Protein–RNA	Heteromer	Protein 2 RNA 1	SIGNAL RECOGNITION PARTICLE PROTEIN × 1 （P0AGD7） 4.5S RNA × 1 PHOSPHOMETHYLPHOSPHONIC ACID GUANYLATE ESTER × 2 MAGNESIUM ION × 2 water × 2	Consistent with all polymers

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	FTSY_ECOLI
Isoform	—
PDB entities	2
Chains and sequence ranges	Author chain B； PDBConstruct 1–302； UniProt 196–497 Author chain D； PDBConstruct 1–302； UniProt 196–497

The page prioritizes protein identity, the current assembly, associated components, oligomeric state and cross-PDB links. Chain mapping and sequence ranges are retained as data evidence. Internal IDs, import timestamps and assembly operation expressions are maintenance fields and are not shown here.

▼

2. Structure Basics 2. Structure Basics

Entry ID entry_id	2xxa
Deposition date deposition_date	2010-11-09
Structure title title	The Crystal Structure of the Signal Recognition Particle (SRP) in Complex with its Receptor(SR)
Keywords keywords	PROTEIN TRANSPORT, RNA/RNA BINDING PROTEIN, HYDROLASE, GTPASE; PROTEIN TRANSPORT
Experimental Method method	X-RAY DIFFRACTION

▼

3. Official assembly/model SAXS Official SAXS Profiles

This page reads only the latest assembly calculations. Every curve maps to an explicit PDB entry, official biological assembly and coordinate model.

2xxa__assembly_2__model_1

Assembly 2 · Model 1 · CRYSOL 4.1.3-1-20251215 (887e7ef)

Download this curve (.dat)

2xxa__assembly_2__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

2xxa__assembly_2__model_1 | P(r) · Pending

P(r) will be calculated and displayed separately for the same assembly/model.

Rg（Guinier）	40.56 Å
Rg (electron density)	39.77 Å
Total Rg	40.16 Å
Atom count	7527
Residues	795
Excluded volume	126340 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`2xxa__assembly_1__model_1`	trimeric （3）	Success	4.1.3-1-20251215 (887e7ef)	View Download
2	1	`2xxa__assembly_2__model_1`	trimeric （3）	Success	4.1.3-1-20251215 (887e7ef)	View Download

▶

4. Crystallography and Experiment 4. Crystallography & Experiment

▶

5. Entities and Polymers Entities & Polymers (6)

Entity 1 Entity 1 polymer

Description description	SIGNAL RECOGNITION PARTICLE PROTEIN
Molecular weight formula_weight	47663.5 kDa
EC 编号 ec_number	3.6.5.4
Mutation mutation	YES
Source method src_method	man
Copy count entity_count	2

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	A,C
Atom count atom_count	15090

MFDNLTDRLSRTLRNISGRGRLTEDNVKDTLREVRMALLEADVALPVVREFINRVKEKAVGHEVNKSLTPGQEFVKIVRNELVAAMGEENQTLNLAAQPPAVVLMAGLQGAGKTTSVGKLGKFLREKHKKKVLVVSADVYRPAAIKQLETLAEQVGVDFFPSDVGQKPVDIVNAALKEAKLKFYDVLLVDTAGRLHVDEAMMDEIKQVHASINPVETLFVVDAMTGQDAANTAKAFNEALPLTGVVLTKVDGDARGGAALSIRHITGKPIKFLGVGEKTEALEPFHPDRIASRILGMGDVLSLIEDIESKVDRAQAEKLASKLKKGDGFDLNDFLEQLRQMKNMGGMASLMGKLPGMGQIPDNVKSQMDDKVLVRMEAIINSMTMKERAKPEIIKGSRKRRIAAGSGMQVQDVNRLLKQFDDMQRMMKKMKKG

Source Source

Source organism organism	ESCHERICHIA COLI K-12
NCBI taxonomy ID ncbi_taxonomy_id	83333
Host organism host_organism	ESCHERICHIA COLI

Entity 2 Entity 2 polymer

Description description	SRP RECEPTOR FTSY
Molecular weight formula_weight	33044.0 kDa
Source method src_method	man
Copy count entity_count	2

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	B,D

FARLKRSLLKTKENLGSGFISLFRGKKIDDDLFEELEEQLLIADVGVETTRKIITNLTEGASRKQLRDAEALYGLLKEEMGEILAKVDEPLNVEGKAPFVILMVGVNGVGKTTTIGKLARQFEQQGKSVMLAAGDTFRAAAVEQLQVWGQRNNIPVIAQHTGADSASVIFDAIQAAKARNIDVLIADTAGRLQNKSHLMEELKKIVRVMKKLDVEAPHEVMLTIDASTGQNAVSQAKLFHEAVGLTGITLTKLDGTAKGGVIFSVADQFGIPIRYIGVGERIEDLRPFKADDFIEALFARED

Source Source

Source organism organism	ESCHERICHIA COLI K-12
NCBI taxonomy ID ncbi_taxonomy_id	83333
Host organism host_organism	ESCHERICHIA COLI

Entity 3 Entity 3 polymer

Description description	4.5S RNA
Molecular weight formula_weight	34238.3 kDa
Source method src_method	syn
Copy count entity_count	2

Polymer Polymer

Polymer type type	polyribonucleotide
Chain IDs strand_id	F,G

GCAUUGCUGGUGCAGCGCAGCGCGGACGCCCGAACCUGGUCAGAGCCGGAAGGCAGCAGCCAUAAGGGAUGCUUUGCGGGUGCCGUUGCCUUCCGGCAAUGCUUUU

Entity 4 Entity 4 non-polymer

Description description	PHOSPHOMETHYLPHOSPHONIC ACID GUANYLATE ESTER
Molecular weight formula_weight	521.2 kDa
Source method src_method	syn
Copy count entity_count	4

Entity 5 Entity 5 non-polymer

Description description	MAGNESIUM ION
Molecular weight formula_weight	24.3 kDa
Source method src_method	syn
Copy count entity_count	4

Entity 6 Entity 6 water

Description description	water
Molecular weight formula_weight	18.0 kDa
Source method src_method	nat
Copy count entity_count	12

▼

6. Fold Classification (SCOP + CATH) 10 domains

CATH v4.4 (10 domains)

Domain ID domain_id	2xxaA01
Class class	1 — Mainly Alpha
Architecture architecture	20 — Up-down Bundle
Topology topology	120 — Four Helix Bundle (Hemerythrin (Met), subunit A)
Homologous superfamily homologous superfamily	140 — SRP54, nucleotide-binding domain

Domain ID domain_id	2xxaA02
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	50 — Rossmann fold
Homologous superfamily homologous superfamily	300 — P-loop containing nucleotide triphosphate hydrolases

Domain ID domain_id	2xxaA03
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	260 — 434 Repressor (Amino-terminal Domain)
Homologous superfamily homologous superfamily	30 — Signal recognition particle, SRP54 subunit, M-domain

Domain ID domain_id	2xxaB01
Class class	1 — Mainly Alpha
Architecture architecture	20 — Up-down Bundle
Topology topology	120 — Four Helix Bundle (Hemerythrin (Met), subunit A)
Homologous superfamily homologous superfamily	140 — SRP54, nucleotide-binding domain

Domain ID domain_id	2xxaB02
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	50 — Rossmann fold
Homologous superfamily homologous superfamily	300 — P-loop containing nucleotide triphosphate hydrolases

Domain ID domain_id	2xxaC01
Class class	1 — Mainly Alpha
Architecture architecture	20 — Up-down Bundle
Topology topology	120 — Four Helix Bundle (Hemerythrin (Met), subunit A)
Homologous superfamily homologous superfamily	140 — SRP54, nucleotide-binding domain

Domain ID domain_id	2xxaC02
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	50 — Rossmann fold
Homologous superfamily homologous superfamily	300 — P-loop containing nucleotide triphosphate hydrolases

Domain ID domain_id	2xxaC03
Class class	1 — Mainly Alpha
Architecture architecture	10 — Orthogonal Bundle
Topology topology	260 — 434 Repressor (Amino-terminal Domain)
Homologous superfamily homologous superfamily	30 — Signal recognition particle, SRP54 subunit, M-domain

Domain ID domain_id	2xxaD01
Class class	1 — Mainly Alpha
Architecture architecture	20 — Up-down Bundle
Topology topology	120 — Four Helix Bundle (Hemerythrin (Met), subunit A)
Homologous superfamily homologous superfamily	140 — SRP54, nucleotide-binding domain

Domain ID domain_id	2xxaD02
Class class	3 — Alpha Beta
Architecture architecture	40 — 3-Layer(aba) Sandwich
Topology topology	50 — Rossmann fold
Homologous superfamily homologous superfamily	300 — P-loop containing nucleotide triphosphate hydrolases

▶

Unit-cell length a length_a	84.100 Å
Unit-cell length b length_b	131.040 Å
Unit-cell length c length_c	266.040 Å
Unit-cell angle α angle_alpha	90.00 °
Unit-cell angle β angle_beta	90.00 °
Unit-cell angle γ angle_gamma	90.00 °
Molecules per unit cell Z z_pdb	8

Space group space_group	P 21 21 21
Space-group number int_tables_number	19
Crystal system crystal_system	—

Resolution resolution	3.940 Å
Low-resolution limit resolution_low	49.300 Å
R factor r_factor	0.2334
R_work r_work	0.2317
R_free r_free	0.2669

The Crystal Structure of the Signal Recognition Particle (SRP) in Complex with its Receptor(SR)

1. Protein Identity and Related Structures Protein Identity & Related Structures

SIGNAL RECOGNITION PARTICLE PROTEIN

State in the Current Structure

Other States of the Same Protein in the Database

SRP RECEPTOR FTSY

State in the Current Structure

Other States of the Same Protein in the Database

2. Structure Basics 2. Structure Basics

3. Official assembly/model SAXS Official SAXS Profiles

2xxa__assembly_2__model_1

2xxa__assembly_2__model_1 | I(q)

2xxa__assembly_2__model_1 | P(r) · Pending

4. Crystallography and Experiment 4. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

Diffraction experiment Diffraction

5. Entities and Polymers Entities & Polymers (6)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 polymer

Polymer Polymer

Source Source

Entity 3 Entity 3 polymer

Polymer Polymer

Entity 4 Entity 4 non-polymer

Entity 5 Entity 5 non-polymer

Entity 6 Entity 6 water

6. Fold Classification (SCOP + CATH) 10 domains

CATH v4.4 (10 domains)

7. Citations (1)

The Crystal Structure of the Signal Recognition Particle (SRP) in Complex with its Receptor(SR)

1. Protein Identity and Related Structures Protein Identity & Related Structures

SIGNAL RECOGNITION PARTICLE PROTEIN

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

SRP RECEPTOR FTSY

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

2. Structure Basics 2. Structure Basics

3. Official assembly/model SAXS Official SAXS Profiles

2xxa__assembly_2__model_1

2xxa__assembly_2__model_1 | I(q)

2xxa__assembly_2__model_1 | P(r) · Pending

4. Crystallography and Experiment 4. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

Diffraction experiment Diffraction

5. Entities and Polymers Entities & Polymers (6)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 polymer

Polymer Polymer

Source Source

Entity 3 Entity 3 polymer

Polymer Polymer

Entity 4 Entity 4 non-polymer

Entity 5 Entity 5 non-polymer

Entity 6 Entity 6 water

6. Fold Classification (SCOP + CATH) 10 domains

CATH v4.4 (10 domains)

7. Citations (1)