PDBsum entry 4tmu

Hydrolase/DNA

PDB id: 4tmu

Contents

Protein chain

511 a.a.

DNA/RNA

Metals

_ZN

Waters ×302

PDB id:

4tmu

Name:

Hydrolase/DNA

Title:

Crystal structure of recq catalytic core from c. Sakazakii bound to DNA

Structure:

Recq. Chain: a. Engineered: yes. Other_details: exact c-terminus not defined, the hrdc domain was removed with thrombin.. DNA (29-mer). Chain: b. Engineered: yes

Source:

Cronobacter sakazakii. Organism_taxid: 290339. Strain: atcc baa-894. Gene: esa_03738. Expressed in: escherichia coli. Expression_system_taxid: 562. Synthetic: yes. Synthetic construct. Organism_taxid: 32630

Resolution:

2.40Å R-factor: 0.181 R-free: 0.233

Authors:

K.A.Manthei,J.L.Keck

Key ref:

K.A.Manthei et al. (2015). Structural mechanisms of DNA binding and unwinding in bacterial RecQ helicases. Proc Natl Acad Sci U S A, 112, 4292-4297. PubMed id: 25831501 DOI: 10.1073/pnas.1416746112

Date:

02-Jun-14 Release date: 11-Mar-15

Protein chain

A7MQK9  (A7MQK9_CROS8) -  DNA helicase from Cronobacter sakazakii (strain ATCC BAA-894)

Seq: 609 a.a.

Struc: 511 a.a.

DNA/RNA chain

G-T-A-G-A-A-T-T-G-A-A-A-T-T-C-T-A-C-C-G-G-T-G-C-C-T-T-A-C 29 bases

Enzyme reactions

• Enzyme class: E.C.3.6.4.12 - Dna helicase.
• Reaction: ATP + H2O = ADP + phosphate + H⁺

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

reference

DOI no: 10.1073/pnas.1416746112

Proc Natl Acad Sci U S A 112:4292-4297 (2015)

PubMed id: 25831501

Structural mechanisms of DNA binding and unwinding in bacterial RecQ helicases.

K.A.Manthei, M.C.Hill, J.E.Burke, S.E.Butcher, J.L.Keck.

ABSTRACT

RecQ helicases unwind remarkably diverse DNA structures as key components of many cellular processes. How RecQ enzymes accommodate different substrates in a unified mechanism that couples ATP hydrolysis to DNA unwinding is unknown. Here, the X-ray crystal structure of the Cronobacter sakazakii RecQ catalytic core domain bound to duplex DNA with a 3' single-stranded extension identifies two DNA-dependent conformational rearrangements: a winged-helix domain pivots ∼90° to close onto duplex DNA, and a conserved aromatic-rich loop is remodeled to bind ssDNA. These changes coincide with a restructuring of the RecQ ATPase active site that positions catalytic residues for ATP hydrolysis. Complex formation also induces a tight bend in the DNA and melts a portion of the duplex. This bending, coupled with translocation, could provide RecQ with a mechanism for unwinding duplex and other DNA structures.