5EZT

Peracetylated Bovine Carbonic Anhydrase II

Summary for 5EZT

• Entry DOI: 10.2210/pdb5ezt/pdb
• Descriptor: Carbonic anhydrase 2, ZINC ION (3 entities in total)
• Functional Keywords: carbonic anhydrase, peracetylated, transferase
• Biological source: Bos taurus (Bovine)
• Cellular location: Cytoplasm: P00921
• Total number of polymer chains: 1
• Total formula weight: 29599.27

Authors

Whitesides, G.M.,Kang, K.,Choi, J.-M.,Fox, J.M. (deposition date: 2015-11-26, release date: 2016-07-20, Last modification date: 2024-10-16)

Primary citation

Kang, K.,Choi, J.M.,Fox, J.M.,Snyder, P.W.,Moustakas, D.T.,Whitesides, G.M.
Acetylation of Surface Lysine Groups of a Protein Alters the Organization and Composition of Its Crystal Contacts.
J.Phys.Chem.B, 120:6461-6468, 2016

PubMed Abstract: This paper uses crystals of bovine carbonic anhydrase (CA) and its acetylated variant to examine (i) how a large negative formal charge can be accommodated in protein-protein interfaces, (ii) why lysine residues are often excluded from them, and (iii) how changes in the surface charge of a protein can alter the structure and organization of protein-protein interfaces. It demonstrates that acetylation of lysine residues on the surface of CA increases the participation of polar residues (particularly acetylated lysine) in protein-protein interfaces, and decreases the participation of nonpolar residues in those interfaces. Negatively charged residues are accommodated in protein-protein interfaces via (i) hydrogen bonds or van der Waals interactions with polar residues or (ii) salt bridges with other charged residues. The participation of acetylated lysine in protein-protein interfaces suggests that unacetylated lysine tends to be excluded from interfaces because of its positive charge, and not because of a loss in conformational entropy. Results also indicate that crystal contacts in acetylated CA become less constrained geometrically and, as a result, more closely packed (i.e., more tightly clustered spatially) than those of native CA. This study demonstrates a physical-organic approach-and a well-defined model system-for studying the role of charges in protein-protein interactions.

PubMed: 27292012
DOI: 10.1021/acs.jpcb.6b01105

Experimental method

X-RAY DIFFRACTION (1.54 Å)