4TZP: As Grown, Untreated Co-crystals Of The Ternary Complex Containing A T- Box Stem I Rna, Its Cognate Trnagly, And B. Subtilis Ybxf Protein

Compared to globular proteins, RNAs with complex 3D folds are characterized by poorly differentiated molecular surfaces dominated by backbone phosphates, sparse tertiary contacts stabilizing global architecture, and conformational flexibility. The resulting generally poor order of crystals of large RNAs and their complexes frequently hampers crystallographic structure determination. We describe and rationalize a postcrystallization treatment strategy that exploits the importance of solvation and counterions for RNA folding. Replacement of Li(+) and Mg(2+) needed for growth of crystals of a tRNA-riboswitch-protein complex with Sr(2+), coupled with dehydration, dramatically improved the resolution limit (8.5-3.2 A) and data quality, enabling structure determination. The soft Sr(2+) ion forms numerous stabilizing intermolecular contacts. Comparison of pre- and posttreatment structures reveals how RNA assemblies redistribute as quasi-rigid bodies to yield improved crystal packing. Cation exchange complements previously reported postcrystallization dehydration of protein crystals and represents a potentially general strategy for improving crystals of large RNAs.
PDB ID: 4TZPDownload
MMDB ID: 123107
PDB Deposition Date: 2014/7/10
Updated in MMDB: 2014/10
Experimental Method:
x-ray diffraction
Resolution: 8.5  Å
Source Organism:
Oceanobacillus iheyensis
Similar Structures:
Biological Unit for 4TZP: trimeric; determined by author
Molecular Components in 4TZP
Label Count Molecule
Protein (1 molecule)
Ribosome-associated Protein L7ae-like(Gene symbol: ybxF)
Molecule annotation
Nucleotides(2 molecules)
Engineered tRNA
Molecule annotation
Glyq T-box Stem I
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB