Interactions of the N-terminal Domain of Ribosomal Protein L11 with Thiostrepton and rRNA

Abstract

Ribosomal protein L11 has two domains: the C-terminal domain (L11-C76) binds rRNA, whereas the N-terminal domain (L11-NTD) may variously interact with elongation factor G, the antibiotic thiostrepton, and rRNA. To begin to quantitate these interactions, L11 from Bacillus stearothermophilus has been overexpressed and its properties compared with those of L11-C76 alone in a fluorescence assay for protein-rRNA binding. The assay relies on 2-amino-butyryl-pyrene-uridine incorporated in a 58-nucleotide rRNA fragment, which gives ϳ15-fold enhancement when L11 or L11-C76 is bound.

Characterization of a Novel Plasmid-Borne Thiopeptide Gene Cluster in Staphylococcus epidermidis Strain 115

“…TclQ is a homolog of 50S ribosomal protein L11, which is located near the ribosomal GTPase center (32,33) and is known to be involved in the mechanism of action of MP1 (9). We hypothesized that TclQ confers immunity by replacing native L11 to protect ribosomes from MP1.…”

A Fluorescent Probe for the 70 S‐Ribosomal GTPase‐Associated Center

“…[24] The K D determined for thiostrepton (1) under homogenous equilibrium conditions with T. thermophilus L11 refines earlier nm estimates. [7,21,22] Nosiheptide (2) was found to bind twice as tightly as thiostrepton (1), whereas micrococcin (3) is an order of magnitude weaker.…”

An α/β-hydrolase fold protein in the biosynthesis of thiostrepton exhibits a dual activity for endopeptidyl hydrolysis and epoxide ring opening/macrocyclization

“…Unexpectedly, during the yield optimization process, we observed a distinct minor product (2′), which appeared with the major product 1′ on day 2 but disappeared over the following fermentation period ( We then scaled up the 4′-supplemented fermentation of SL1102 and accumulated a sufficient quantity of 2′ for structural elucidation. Consequently, 1D, 2D, and 19 F NMR analyses of the extract from 500 L of the culture broth confirmed the identity of 2′ to 6′-fluoro-7′, 8′-epoxy-TSR (SI Appendix, Fig. S6), which possesses a thiopeptide framework that is identical to that of 1′ in amino acid composition and modification as well as 6′-fluoro-QA attachment (Fig.…”

“…The mechanism by which QA is incorporated to construct the side-ring system of TSR remains poorly understood (17). Unlike current clinically used chemotherapeutics that target the bacterial ribosome (18), many thiopeptides, including TSR, display potent activity against various drugresistant pathogens by perturbing translation factor binding and subsequent protein synthesis, largely upon the occupation of the common thiopeptide framework within a cleft located between the L11 protein and the 23S rRNA of the large ribosomal subunit (19). Although a total of only 14% of the surface…”