1HPM

HOW POTASSIUM AFFECTS THE ACTIVITY OF THE MOLECULAR CHAPERONE HSC70. II. POTASSIUM BINDS SPECIFICALLY IN THE ATPASE ACTIVE SITE

PDB DOI: https://doi.org/10.2210/pdb1HPM/pdb

Classification: HYDROLASE (ACTING ON ACID ANHYDRIDES)
Organism(s): Bos taurus
Expression System: Escherichia coli
Mutation(s): No

Deposited: 1995-03-24 Released: 1995-07-31
Deposition Author(s): Wilbanks, S.M., Mckay, D.B.

Experimental Data Snapshot

Method: X-RAY DIFFRACTION
Resolution: 1.70 Å
R-Value Work: 0.205
R-Value Observed: 0.205

wwPDB Validation 3D Report Full Report

This is version 1.3 of the entry. See complete history.

Literature

How potassium affects the activity of the molecular chaperone Hsc70. II. Potassium binds specifically in the ATPase active site.

Wilbanks, S.M., McKay, D.B.

(1995) J Biol Chem 270: 2251-2257

PubMed: 7836458 Search on PubMed
DOI: https://doi.org/10.1074/jbc.270.5.2251
Primary Citation of Related Structures:
1HPM

PubMed Abstract:
Crystallographic anomalous scattering from potassium at 1.7 A resolution reveals two monovalent ions that interact with MgADP and P(i) in the nucleotide binding cleft of wild-type recombinant bovine Hsc70 ATPase fragment. K+ at site 1 interacts with oxygens of the beta-phosphate of ADP, whereas K+ at site 2 interacts with an oxygen of P(i). Both K+ ions also interact with specific H2O molecules in the first hydration shell of the octahedrally coordinated Mg2+ ion and with specific protein ligands. In crystals that have Na+ present, K+ is replaced by a Na+ ion at site 1 and by a Na(+)-H2O pair at site 2. The K+ ions are positioned where they could stabilize binding of a beta,gamma-bidentate MgATP complex with Hsc70, as well as a transition state during ATP hydrolysis, suggesting that monovalent ions act as specific metal cofactors in the ATPase reaction of Hsc70.

Organizational Affiliation

Beckman Laboratories for Structural Biology, Stanford University School of Medicine, California 94305.

Macromolecule Content

Total Structure Weight: 43.21 kDa
Atom Count: 3,360
Modelled Residue Count: 378
Deposited Residue Count: 386
Unique protein chains: 1

Macromolecules

Find similar proteins by:

(by identity cutoff) | 3D Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
44K ATPASE FRAGMENT (N-TERMINAL) OF 7O kD HEAT-SHOCK COGNATE PROTEIN	A	386	Bos taurus	Mutation(s): 0 EC: 3.6.1.3 (PDB Primary Data), 3.6.4.10 (UniProt)
UniProt
Find proteins for P19120 (Bos taurus) Explore P19120 Go to UniProtKB: P19120
Entity Groups
Sequence Clusters	30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt Group	P19120
Sequence Annotations Expand
Reference Sequence

Small Molecules

Ligands 5 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram	3D Interactions
ADP Query on ADP Download Ideal Coordinates CCD File SDF format, chain H [auth A] MOL2 format, chain H [auth A] mmCIF format, chain H [auth A]	H [auth A]	ADENOSINE-5'-DIPHOSPHATE C₁₀ H₁₅ N₅ O₁₀ P₂ XTWYTFMLZFPYCI-KQYNXXCUSA-N		Interactions Focus chain H [auth A]
PO4 Query on PO4 Download Ideal Coordinates CCD File SDF format, chain C [auth A] MOL2 format, chain C [auth A] mmCIF format, chain C [auth A]	C [auth A]	PHOSPHATE ION O₄ P NBIIXXVUZAFLBC-UHFFFAOYSA-K		Interactions Focus chain C [auth A]
K Query on K Download Ideal Coordinates CCD File SDF format, chain D [auth A] SDF format, chain E [auth A] MOL2 format, chain D [auth A] MOL2 format, chain E [auth A] mmCIF format, chain D [auth A] mmCIF format, chain E [auth A]	D [auth A], E [auth A]	POTASSIUM ION K NPYPAHLBTDXSSS-UHFFFAOYSA-N		Interactions Focus chain D [auth A] Focus chain E [auth A]
CL Query on CL Download Ideal Coordinates CCD File SDF format, chain F [auth A] SDF format, chain G [auth A] MOL2 format, chain F [auth A] MOL2 format, chain G [auth A] mmCIF format, chain F [auth A] mmCIF format, chain G [auth A]	F [auth A], G [auth A]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M		Interactions Focus chain F [auth A] Focus chain G [auth A]
MG Query on MG Download Ideal Coordinates CCD File SDF format, chain B [auth A] MOL2 format, chain B [auth A] mmCIF format, chain B [auth A]	B [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N		Interactions Focus chain B [auth A]

Binding Affinity Annotations
ID	Source	Binding Affinity
ADP	BindingDB: 1HPM	Kd: min: 320, max: 324 (nM) from 2 assay(s)
ADP	BindingDB: 1HPM	IC50: 280 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

Method: X-RAY DIFFRACTION
Resolution: 1.70 Å
R-Value Work: 0.205
R-Value Observed: 0.205
Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 143.9	α = 90
b = 63.7	β = 90
c = 46.2	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

View Full Validation Report

Entry History

Deposition Data

Released Date: 1995-07-31

Deposition Author(s):

Wilbanks, S.M.

Mckay, D.B.

Revision History (Full details and data files)

Version 1.0: 1995-07-31
Type: Initial release
Version 1.1: 2008-03-24
Changes: Version format compliance
Version 1.2: 2011-07-13
Changes: Version format compliance
Version 1.3: 2024-02-07
Changes: Data collection, Database references, Derived calculations, Other