3B1B

The unique structure of wild type carbonic anhydrase alpha-CA1 from Chlamydomonas reinhardtii

Summary for 3B1B

• Entry DOI: 10.2210/pdb3b1b/pdb
• Descriptor: Carbonic anhydrase 1, ZINC ION, SULFATE ION, ... (5 entities in total)
• Functional Keywords: n-glycosylation, zinc-finger, carbonic anhydrase, lyase
• Biological source: Chlamydomonas reinhardtii
• Total number of polymer chains: 2
• Total formula weight: 84886.59

Authors

Shimizu, S.,Takenaka, A. (deposition date: 2011-06-29, release date: 2011-11-16, Last modification date: 2024-10-30)

Primary citation

Suzuki, K.,Yang, S.Y.,Shimizu, S.,Morishita, E.C.,Jiang, J.,Zhang, F.,Hoque, M.M.,Sato, Y.,Tsunoda, M.,Sekiguchi, T.,Takenaka, A.
The unique structure of carbonic anhydrase alpha CA1 from Chlamydomonas reinhardtii
Acta Crystallogr.,Sect.D, 67:894-901, 2011

PubMed Abstract: Chlamydomonas reinhardtii α-type carbonic anhydrase (Cr-αCA1) is a dimeric enzyme that catalyses the interconversion of carbon dioxide and carbonic acid. The precursor form of Cr-αCA1 undergoes post-translational cleavage and N-glycosylation. Comparison of the genomic sequences of precursor Cr-αCA1 and other αCAs shows that Cr-αCA1 contains a different N-terminal sequence and two insertion sequences. A 35-residue peptide in one of the insertion sequences is deleted from the precursor during maturation. The crystal structure of the mature form of Cr-αCA1 has been determined at 1.88 Å resolution. Each subunit is cleaved into the long and short peptides, but they are linked together by a disulfide bond. The two subunits are linked by a disulfide bond. N-Glycosylations occur at three asparagine residues and the attached N-glycans protrude into solvent regions. The subunits consist of a core β-sheet structure composed of nine β-strands. At the centre of the β-sheet is the catalytic site, which contains a Zn atom bound to three histidine residues. The amino-acid residues around the Zn atom are highly conserved in other monomeric and dimeric αCAs. The short peptide runs near the active site and forms a hydrogen bond to the zinc-coordinated residue in the long chain, suggesting an important role for the short peptide in Cr-αCA1 activity.

PubMed: 21931221
DOI: 10.1107/S0907444911032884

Experimental method

X-RAY DIFFRACTION (1.88 Å)