Crystal structures reveal an elusive functional domain of pyrrolysyl-tRNA synthetase.

ABSTRACT: Pyrrolysyl-tRNA synthetase (PylRS) is a major tool in genetic code expansion using noncanonical amino acids, yet its structure and function are not completely understood. Here we describe the crystal structure of the previously uncharacterized essential N-terminal domain of this unique enzyme in complex with tRNA^Pyl. This structure explains why PylRS remains orthogonal in a broad range of organisms, from bacteria to humans. The structure also illustrates why tRNA^Pyl recognition by PylRS is anticodon independent: the anticodon does not contact the enzyme. Then, using standard microbiological culture equipment, we established a new method for laboratory evolution-a noncontinuous counterpart of the previously developed phage-assisted continuous evolution. With this metho

SUBMITTER: Suzuki T 

PROVIDER: S-EPMC5698177 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature