1T6H

Crystal Structure T4 Lysozyme incorporating an unnatural amino acid p-iodo-L-phenylalanine at position 153

Summary for 1T6H

• Entry DOI: 10.2210/pdb1t6h/pdb
• Related: 1L63
• Descriptor: Lysozyme, CHLORIDE ION, BETA-MERCAPTOETHANOL, ... (4 entities in total)
• Functional Keywords: iodophe, sad phasing, unnatural amino acid, hydrolase
• Biological source: Enterobacteria phage T4
• Cellular location: Host cytoplasm : P00720
• Total number of polymer chains: 1
• Total formula weight: 19050.99

Authors

Spraggon, G.,Xie, J.,Wang, L.,Wu, N.,Brock, A.,Schultz, P.G. (deposition date: 2004-05-06, release date: 2004-10-26, Last modification date: 2025-03-26)

Primary citation

Xie, J.,Wang, L.,Wu, N.,Brock, A.,Spraggon, G.,Schultz, P.G.
The site-specific incorporation of p-iodo-L-phenylalanine into proteins for structure determination.
Nat.Biotechnol., 22:1297-1301, 2004

PubMed Abstract: A recently developed method makes it possible to genetically encode unnatural amino acids with diverse physical, chemical or biological properties in Escherichia coli and yeast. We now show that this technology can be used to efficiently and site-specifically incorporate p-iodo-L-phenylalanine (iodoPhe) into proteins in response to an amber TAG codon. The selective introduction of the anomalously scattering iodine atom into proteins should facilitate single-wavelength anomalous dispersion experiments on in-house X-ray sources. To illustrate this, we generated a Phe153 --> iodoPhe mutant of bacteriophage T4 lysozyme and determined its crystal structure using considerably less data than are needed for the equivalent experiment with cysteine and methionine. The iodoPhe residue, although present in the hydrophobic core of the protein, did not perturb the protein structure in any meaningful way. The ability to selectively introduce this and other heavy atom-containing amino acids into proteins should facilitate the structural study of proteins.

PubMed: 15378068
DOI: 10.1038/nbt1013

Experimental method

X-RAY DIFFRACTION (2.01 Å)