1CZ0

INTRON ENCODED HOMING ENDONUCLEASE I-PPOI/DNA COMPLEX LACKING CATALYTIC METAL ION

Summary for 1CZ0

• Entry DOI: 10.2210/pdb1cz0/pdb
• Related: 1A73 1A74 1CYQ 1IPP
• Descriptor: DNA (5'-D(*TP*TP*GP*AP*CP*TP*CP*TP*CP*TP*TP*AP*AP*GP*AP*GP*AP*GP*TP*CP*A)-3'), INTRON-ENCODED HOMING ENDONUCLEASE I-PPOI, SODIUM ION, ... (5 entities in total)
• Functional Keywords: protein-dna complex, distorted dna, his-cys box zinc binding site, beta sheet dna binding, hydrolase-dna complex, hydrolase/dna
• Biological source: Physarum polycephalum; More
• Total number of polymer chains: 4
• Total formula weight: 48542.08

Authors

Galburt, E.A.,Chevalier, B.,Jurica, M.S.,Flick, K.E.,Stoddard, B.L. (deposition date: 1999-08-31, release date: 1999-11-19, Last modification date: 2024-02-07)

Primary citation

Galburt, E.A.,Chevalier, B.,Tang, W.,Jurica, M.S.,Flick, K.E.,Monnat Jr., R.J.,Stoddard, B.L.
A novel endonuclease mechanism directly visualized for I-PpoI.
Nat.Struct.Biol., 6:1096-1099, 1999

PubMed Abstract: A novel mechanism of DNA endonucleolytic cleavage has been visualized for the homing endonuclease I-PpoI by trapping the uncleaved enzyme-substrate complex and comparing it to the previously visualized product complex. This enzyme employs a unique single metal mechanism. A magnesium ion is coordinated by an asparagine residue and two DNA oxygen atoms and stabilizes the phosphoanion transition state and the 3'oxygen leaving group. A hydrolytic water molecule is activated by a histidine residue for an in-line attack on the scissile phosphate. A strained enzyme-substrate-metal complex is formed before cleavage, then relaxed during the reaction.

PubMed: 10581547
DOI: 10.1038/70027

Experimental method

X-RAY DIFFRACTION (2.1 Å)