PDBsum entry 5c3c

Protein binding

PDB id: 5c3c

Contents

Protein chains

231 a.a.

235 a.a.

Ligands

ADP ×2

PDB id:

5c3c

Name:

Protein binding

Title:

Structural characterization of a newly identified component of alpha- carboxysomes: the aaa+ domain protein cso-cbbq

Structure:

Cbbq/nirq/norq domain protein. Chain: a, b. Engineered: yes

Source:

Halothiobacillus neapolitanus (strain atcc 23641 / c2). Organism_taxid: 555778. Strain: atcc 23641 / c2. Gene: hneap_0905. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

2.80Å R-factor: 0.231 R-free: 0.283

Authors:

M.Sutter,C.A.Kerfeld

Key ref:

M.Sutter et al. (2015). Structural Characterization of a Newly Identified Component of α-Carboxysomes: The AAA+ Domain Protein CsoCbbQ. Sci Rep, 5, 16243. PubMed id: 26538283 DOI: 10.1038/srep16243

Date:

17-Jun-15 Release date: 18-Nov-15

Protein chain

D0KZ75  (D0KZ75_HALNC) -  CbbQ/NirQ/NorQ domain protein from Halothiobacillus neapolitanus (strain ATCC 23641 / c2)

Seq: 267 a.a.

Struc: 231 a.a.

Protein chain

D0KZ75  (D0KZ75_HALNC) -  CbbQ/NirQ/NorQ domain protein from Halothiobacillus neapolitanus (strain ATCC 23641 / c2)

Seq: 267 a.a.

Struc: 235 a.a.

Enzyme reactions

• Enzyme class: Chains A, B: E.C.?

DOI no: 10.1038/srep16243

Sci Rep 5:16243 (2015)

PubMed id: 26538283

Structural Characterization of a Newly Identified Component of α-Carboxysomes: The AAA+ Domain Protein CsoCbbQ.

M.Sutter, E.W.Roberts, R.C.Gonzalez, C.Bates, S.Dawoud, K.Landry, G.C.Cannon, S.Heinhorst, C.A.Kerfeld.

ABSTRACT

Carboxysomes are bacterial microcompartments that enhance carbon fixation by concentrating ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and its substrate CO2 within a proteinaceous shell. They are found in all cyanobacteria, some purple photoautotrophs and many chemoautotrophic bacteria. Carboxysomes consist of a protein shell that encapsulates several hundred molecules of RuBisCO, and contain carbonic anhydrase and other accessory proteins. Genes coding for carboxysome shell components and the encapsulated proteins are typically found together in an operon. The α-carboxysome operon is embedded in a cluster of additional, conserved genes that are presumably related to its function. In many chemoautotrophs, products of the expanded carboxysome locus include CbbO and CbbQ, a member of the AAA+ domain superfamily. We bioinformatically identified subtypes of CbbQ proteins and show that their genes frequently co-occur with both Form IA and Form II RuBisCO. The α-carboxysome-associated ortholog, CsoCbbQ, from Halothiobacillus neapolitanus forms a hexamer in solution and hydrolyzes ATP. The crystal structure shows that CsoCbbQ is a hexamer of the typical AAA+ domain; the additional C-terminal domain, diagnostic of the CbbQ subfamily, structurally fills the inter-monomer gaps, resulting in a distinctly hexagonal shape. We show that CsoCbbQ interacts with CsoCbbO and is a component of the carboxysome shell, the first example of ATPase activity associated with a bacterial microcompartment.