Back to Search
Start Over
Structural and DNA binding properties of mycobacterial integration host factor mIHF
- Source :
- Journal of Structural Biology, Journal of Structural Biology, Elsevier, 2020, 209 (3), pp.107434. ⟨10.1016/j.jsb.2019.107434⟩
- Publication Year :
- 2020
- Publisher :
- HAL CCSD, 2020.
-
Abstract
- In bacteria, nucleoid associated proteins (NAPs) take part in active chromosome organization by supercoil management, three-dimensional DNA looping and direct transcriptional control. Mycobacterial integration host factor (mIHF, rv1388) is a NAP restricted to Actinobacteria and essential for survival of the human pathogen Mycobacterium tuberculosis. We show in vitro that DNA binding by mIHF strongly stabilizes the protein and increases its melting temperature. The structure obtained by Nuclear Magnetic Resonance (NMR) spectroscopy characterizes mIHF as a globular protein with a protruding alpha helix and a disordered N-terminus, similar to Streptomyces coelicolor IHF (sIHF). NMR revealed no residues of high flexibility, suggesting that mIHF is a rigid protein overall that does not undergo structural rearrangements. We show that mIHF only binds to double stranded DNA in solution, through two DNA binding sites (DBSs) similar to those identified in the x-ray structure of sIHF. According to Atomic Force Microscopy, mIHF is able to introduce left-handed loops of ca. 100 nm size (∼300 bp) in supercoiled cosmids, thereby unwinding and relaxing the DNA.
- Subjects :
- DNA, Bacterial
Integration Host Factors
Protein Conformation, alpha-Helical
Magnetic Resonance Spectroscopy
Nucleoid Associated Protein
Globular protein
[SDV]Life Sciences [q-bio]
mIHF
Streptomyces coelicolor
Microscopy, Atomic Force
DNA-binding protein
03 medical and health sciences
chemistry.chemical_compound
Structural Biology
lsr2
Nucleoid
Humans
Tuberculosis
DNA binding
Mycobacterial Integration Host Factor
ComputingMilieux_MISCELLANEOUS
030304 developmental biology
chemistry.chemical_classification
0303 health sciences
Binding Sites
atomic force microscopy
biology
030302 biochemistry & molecular biology
nucleoid-associated proteins
dynamics
Mycobacterium tuberculosis
NMR structural determination
biology.organism_classification
3. Good health
DNA binding site
nmr structure determination
DNA-Binding Proteins
assignment
chemistry
regulator
bacterial chromatin
Host-Pathogen Interactions
Biophysics
DNA supercoil
systems
DNA
Alpha helix
Subjects
Details
- Language :
- English
- ISSN :
- 10478477 and 10958657
- Database :
- OpenAIRE
- Journal :
- Journal of Structural Biology, Journal of Structural Biology, Elsevier, 2020, 209 (3), pp.107434. ⟨10.1016/j.jsb.2019.107434⟩
- Accession number :
- edsair.doi.dedup.....78d4cade1d72c51f4ccc98af8a928b78