PDBsum entry 6b47

Immune system / RNA

PDB id: 6b47

Contents

Protein chains

424 a.a.

305 a.a.

293 a.a.

333 a.a.

87 a.a.

189 a.a.

DNA/RNA

PDB id:

6b47

Name:

Immune system / RNA

Title:

Cryo-em structure of type i-f crispr crrna-guided csy surveillance complex with bound anti-crispr protein acrf2

Structure:

Crispr-associated protein csy1. Chain: a. Engineered: yes. Crispr-associated protein csy2. Chain: b. Engineered: yes. Crispr-associated protein csy3. Chain: c, d, e, f, g, h. Engineered: yes.

Source:

Pseudomonas aeruginosa (strain ucbpp-pa14). Organism_taxid: 208963. Strain: ucbpp-pa14. Gene: csy1, pa14_33330. Expressed in: escherichia coli. Expression_system_taxid: 469008. Gene: csy2, pa14_33320. Gene: csy3, csy1-3, pa14_33310. Pseudomonas phage d3112.

Authors:

T.W.Guo,A.Bartesaghi,H.Yang,V.Falconieri,P.Rao,A.Merk,T.Fox,L.Earl, D.J.Patel,S.Subramaniam

Key ref:

T.W.Guo et al. (2017). Cryo-EM Structures Reveal Mechanism and Inhibition of DNA Targeting by a CRISPR-Cas Surveillance Complex. Cell, 171, 414. PubMed id: 28985564

Date:

25-Sep-17 Release date: 18-Oct-17

Protein chain

Q02ML9  (CSY1_PSEAB) -  CRISPR-associated protein Csy1 from Pseudomonas aeruginosa (strain UCBPP-PA14)

Seq: 434 a.a.

Struc: 424 a.a.

Protein chain

Q02MM0  (CSY2_PSEAB) -  CRISPR-associated protein Csy2 from Pseudomonas aeruginosa (strain UCBPP-PA14)

Seq: 327 a.a.

Struc: 305 a.a.

Protein chain

Q02MM1  (CSY3_PSEAB) -  CRISPR-associated protein Csy3 from Pseudomonas aeruginosa (strain UCBPP-PA14)

Seq: 342 a.a.

Struc: 293 a.a.

Protein chains

Q02MM1  (CSY3_PSEAB) -  CRISPR-associated protein Csy3 from Pseudomonas aeruginosa (strain UCBPP-PA14)

Seq: 342 a.a.

Struc: 333 a.a.

Protein chain

Q6TM72  (ACR30_BPD31) -  Anti-CRISPR protein 30 from Pseudomonas phage D3112

Seq: 90 a.a.

Struc: 87 a.a.

Protein chain

Q02MM2  (CAS6_PSEAB) -  CRISPR-associated endonuclease Cas6/Csy4 from Pseudomonas aeruginosa (strain UCBPP-PA14)

Seq: 187 a.a.

Struc: 189 a.a.

DNA/RNA chain

C-U-A-A-G-A-A-A-U-U-C-A-C-G-G-C-G-G-G-C-U-U-G-A-U-G-U-C-C-G-C-G-U-C-U-A-C-C-U- 60 bases

Enzyme reactions

• Enzyme class: Chain L: E.C.3.1.-.-

Cell 171:414 (2017)

PubMed id: 28985564

Cryo-EM Structures Reveal Mechanism and Inhibition of DNA Targeting by a CRISPR-Cas Surveillance Complex.

T.W.Guo, A.Bartesaghi, H.Yang, V.Falconieri, P.Rao, A.Merk, E.T.Eng, A.M.Raczkowski, T.Fox, L.A.Earl, D.J.Patel, S.Subramaniam.

ABSTRACT

Prokaryotic cells possess CRISPR-mediated adaptive immune systems that protect them from foreign genetic elements, such as invading viruses. A central element of this immune system is an RNA-guided surveillance complex capable of targeting non-self DNA or RNA for degradation in a sequence- and site-specific manner analogous to RNA interference. Although the complexes display considerable diversity in their composition and architecture, many basic mechanisms underlying target recognition and cleavage are highly conserved. Using cryoelectron microscopy (cryo-EM), we show that the binding of target double-stranded DNA (dsDNA) to a type I-F CRISPR system yersinia (Csy) surveillance complex leads to large quaternary and tertiary structural changes in the complex that are likely necessary in the pathway leading to target dsDNA degradation by a trans-acting helicase-nuclease. Comparison of the structure of the surveillance complex before and after dsDNA binding, or in complex with three virally encoded anti-CRISPR suppressors that inhibit dsDNA binding, reveals mechanistic details underlying target recognition and inhibition.