5ENL

INHIBITION OF ENOLASE: THE CRYSTAL STRUCTURES OF ENOLASE-CA2+-PHOSPHOGLYCERATE AND ENOLASE-ZN2+-PHOSPHOGLYCOLATE COMPLEXES AT 2.2-ANGSTROMS RESOLUTION

Summary for 5ENL

• Entry DOI: 10.2210/pdb5enl/pdb
• Descriptor: ENOLASE, CALCIUM ION, 2-PHOSPHOGLYCERIC ACID, ... (4 entities in total)
• Functional Keywords: carbon-oxygen lyase
• Biological source: Saccharomyces cerevisiae (baker's yeast)
• Cellular location: Cytoplasm : P00924
• Total number of polymer chains: 1
• Total formula weight: 46916.83

Authors

Lebioda, L.,Stec, B. (deposition date: 1990-11-13, release date: 1992-04-15, Last modification date: 2024-03-13)

Primary citation

Lebioda, L.,Stec, B.,Brewer, J.M.,Tykarska, E.
Inhibition of enolase: the crystal structures of enolase-Ca2(+)- 2-phosphoglycerate and enolase-Zn2(+)-phosphoglycolate complexes at 2.2-A resolution.
Biochemistry, 30:2823-2827, 1991

PubMed Abstract: Enolase is a metalloenzyme which catalyzes the elimination of H2O from 2-phosphoglyceric acid (PGA) to form phosphoenolpyruvate (PEP). Mg2+ and Zn2+ are cofactors which strongly bind and activate the enzyme. Ca2+ also binds strongly but does not produce activity. Phosphoglycolate (PG) is a competitive inhibitor of enolase. The structures of two inhibitory ternary complexes: yeast enolase-Ca2(+)-PGA and yeast enolase-Zn2(+)-PG, were determined by X-ray diffraction to 2.2-A resolution and were refined by crystallographic least-squares to R = 14.8% and 15.7%, respectively, with good geometries of the models. These structures are compared with the structure of the precatalytic ternary complex enolase-Mg2(+)-PGA/PEP (Lebioda & Stec, 1991). In the complex enolase-Ca2(+)-PGA, the PGA molecule coordinates to the Ca2+ ion with the hydroxyl group, as in the precatalytic complex. The conformation of the PGA molecule is however different. In the active complex, the organic part of the PGA molecule is planar, similar to the product. In the inhibitory complex, the carboxylic group is in an orthonormal conformation. In the inhibitory complex enolase-Zn2(+)-PG, the PG molecule coordinates with the carboxylic group in a monodentate mode. In both inhibitory complexes, the conformational changes in flexible loops, which were observed in the precatalytic complex, do not take place. The lack of catalytic metal ion binding suggests that these conformational changes are necessary for the formation of the catalytic metal ion binding site.

PubMed: 2007121
DOI: 10.1021/bi00225a013

Experimental method

X-RAY DIFFRACTION (2.2 Å)