PDBsum entry 4z7l

Hydrolase/RNA

PDB id: 4z7l

Contents

Protein chains

218 a.a.

193 a.a.

170 a.a.

174 a.a.

DNA/RNA

Ligands

SO4 ×3

PDB id:

4z7l

Name:

Hydrolase/RNA

Title:

Crystal structure of cas6b

Structure:

Cas6b. Chain: a, b, d, g, e, h. Engineered: yes. RNA (5'-r( Gp Cp Ap Ap Ap Ap Up Ap Ap Cp Ap Ap Gp C)-3'). Chain: c, f, i. Engineered: yes

Source:

Methanococcus maripaludis (strain c5 / atcc baa-1333). Organism_taxid: 402880. Strain: c5 / atcc baa-1333. Gene: mmarc5_0767. Expressed in: escherichia coli. Expression_system_taxid: 562. Methanococcus maripaludis. Organism_taxid: 39152.

Resolution:

3.50Å R-factor: 0.246 R-free: 0.290

Authors:

H.Li

Key ref:

Y.Shao et al. (2016). A Non-Stem-Loop CRISPR RNA Is Processed by Dual Binding Cas6. Structure, 24, 547-554. PubMed id: 26996962

Date:

07-Apr-15 Release date: 13-Apr-16

Protein chains

A4FXZ3  (A4FXZ3_METM5) -  DNA repair protein from Methanococcus maripaludis (strain C5 / ATCC BAA-1333)

Seq: 218 a.a.

Struc: 218 a.a.

Protein chain

A4FXZ3  (A4FXZ3_METM5) -  DNA repair protein from Methanococcus maripaludis (strain C5 / ATCC BAA-1333)

Seq: 218 a.a.

Struc: 193 a.a.

Protein chain

A4FXZ3  (A4FXZ3_METM5) -  DNA repair protein from Methanococcus maripaludis (strain C5 / ATCC BAA-1333)

Seq: 218 a.a.

Struc: 170 a.a.

Protein chain

A4FXZ3  (A4FXZ3_METM5) -  DNA repair protein from Methanococcus maripaludis (strain C5 / ATCC BAA-1333)

Seq: 218 a.a.

Struc: 174 a.a.

DNA/RNA chains

G-C-A-A-A-A-U-A-A-C-A-A-G-C 14 bases

G-C-A-A-A-A-U-A-A-C-A-A-G-C 14 bases

G-C-A-A-A-A-U-A-A-C-A-A-G-C 14 bases

Structure 24:547-554 (2016)

PubMed id: 26996962

A Non-Stem-Loop CRISPR RNA Is Processed by Dual Binding Cas6.

Y.Shao, H.Richter, S.Sun, K.Sharma, H.Urlaub, L.Randau, H.Li.

ABSTRACT

A subclass of recently discovered CRISPR repeat RNA in bacteria contains minimally recognizable structural features that facilitate an unknown mechanism of recognition and processing by the Cas6 family of endoribonucleases. Cocrystal structures of Cas6 from Methanococcus maripaludis (MmCas6b) bound with its repeat RNA revealed a dual site binding structure and a cleavage site conformation poised for phosphodiester bond breakage. Two non-interacting MmCas6b bind to two separate AAYAA motifs within the same repeat, one distal and one adjacent to the cleavage site. This bound structure potentially competes with a stable but non-productive RNA structure. At the cleavage site, MmCas6b supplies a base pair mimic to stabilize a short 2 base pair stem immediately upstream of the scissile phosphate. Complementary biochemical analyses support the dual-AAYAA binding model and a critical role of the protein-RNA base pair mimic. Our results reveal a previously unknown method of processing non-stem-loop CRISPR RNA by Cas6.