Download MendeleyStructural Insights Into Peptide Bond Formation
Hansen, J.L., Schmeing, T.M., Moore, P.B., Steitz, T.A.(2002) Proc Natl Acad Sci U S A 99: 11670-11675
- PubMed: 12185246
- DOI: https://doi.org/10.1073/pnas.172404099
- Primary Citation of Related Structures:
1M90, 1Q7Y, 1Q81, 1Q82, 1Q86 - PubMed Abstract:
The large ribosomal subunit catalyzes peptide bond formation and will do so by using small aminoacyl- and peptidyl-RNA fragments of tRNA. We have refined at 3-A resolution the structures of both A and P site substrate and product analogues, as well as an intermediate analogue, bound to the Haloarcula marismortui 50S ribosomal subunit. A P site substrate, CCA-Phe-caproic acid-biotin, binds equally to both sites, but in the presence of sparsomycin binds only to the P site. The CCA portions of these analogues are bound identically by either the A or P loop of the 23S rRNA. Combining the separate P and A site substrate complexes into one model reveals interactions that may occur when both are present simultaneously. The alpha-NH(2) group of an aminoacylated fragment in the A site forms one hydrogen bond with the N3 of A2486 (2451) and may form a second hydrogen bond either with the 2' OH of the A-76 ribose in the P site or with the 2' OH of A2486 (2451). These interactions position the alpha amino group adjacent to the carbonyl carbon of esterified P site substrate in an orientation suitable for a nucleophilic attack.
Organizational Affiliation:
Department of Molecular Biophysics and Biochemistry, Yale University, 266 Whitney Avenue, New Haven, CT 06520-8114, USA.
