Extended structure of pleiotropic DNA repair-promoting protein PprA from Deinococcus radiodurans.
FASEB J
; 33(3): 3647-3658, 2019 03.
Article
in En
| MEDLINE
| ID: mdl-30481062
ABSTRACT
Pleiotropic protein promoting DNA repair A (PprA) is a key protein facilitating the extreme radiation resistance of Deinococcus radiodurans. PprA is a unique protein to the genus Deinococcus and exists as an oligomer ranging from a tetramer to an â¼100-mer depending on protein concentrations. Here, the X-ray crystal structure of PprA was determined to clarify how PprA confers radiation resistance. The tertiary structure of dimeric PprA was elucidated by using mutants obtained with random and site-directed mutagenesis methods (W183R and A139R); these mutants have disabled DNA binding and polymerization functions. Because the mutant A139R and W183R proteins have dimeric assemblies with 2 different interfaces (Interfaces 1 and 2), the linear and oligomerized PprA model was constructed as a left-handed face-to-face periodic screw structure. In addition, the linear structure in solution was confirmed by small-angle scattering experiments. The site-directed mutational analysis identified essential basic amino acids for DNA binding. These analytical data support the hypothesis that a complex assembly of PprA molecules, which are extended and have a screw structure, surrounds and stretches the DNA strand, acting as a novel guide to colocalize the DNA strands for efficient DNA repairs.-Adachi, M., Shimizu, R., Shibazaki, C., Satoh, K., Fujiwara, S., Arai, S., Narumi, I., Kuroki, R. Extended structure of pleiotropic DNA repair-promoting protein PprA from Deinococcus radiodurans.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Bacterial Proteins
/
Deinococcus
/
DNA Repair
Language:
En
Journal:
FASEB J
Journal subject:
BIOLOGIA
/
FISIOLOGIA
Year:
2019
Document type:
Article
Affiliation country:
Japón