7 t ltq ft

¹H-NMR spectra were recorded on a Hermes-Varian Mercury Plus 300 (300 MHz) spectrometer at room temperature. Chemical shifts were recorded in parts per million (ppm) using residual solvent peaks as internal references [MeOH-d₄ δ: 4.5 (¹H) and DMSO-d6 δ: 2.5]. Electro spray ionization mass spectra for the synthesized ligand molecules were obtained using a Waters (Micromass) LCT^® mass spectrometer (Waters, Beverly, MA) similarly as described previously.^{46 (link)} High-resolution Fourier transformed ion cyclotron resonance (FT-ICR) mass spectra before and after UV irradiation were obtained on a 7 T LTQ/FT (Thermo Scientific, Waltham, MA), similarly as described in our previous publication.^{11 (link)} DLS was carried out using a Malvern Zetasizer Nano. All DLS measurements of individual samples were performed three times after 120 sec equilibration.

Peptides were resuspended in solvent A (95% water, 5% acetonitrile, and 0.2% formic acid) and 5 μL were injected onto a trap column (150 μm ID × 3 cm) coupled with a nanobore analytical column (75 μm ID × 15 cm). The trap and analytical columns were packed with C18 reversed phase (Magic C18, Bruker) media (3 μm, 100 Å pore size). Samples were separated by UPLC using a linear gradient of solvent A and solvent B (5% water, 95% acetonitrile, 0.2% formic acid) delivered over 60–90 minutes by a Dionex UltiMate 3000 nano-LC (Thermo). MS data were obtained on either a 7T LTQ-FT or a 12T Velos-FT (Thermo) mass spectrometer fitted with a custom nanospray ionization source. Intact mass spectrometry data were obtained at an FT resolving power of 60,000 (at m/z 400). The top 5 or 10 m/z species were isolated within the ion trap and fragmented using collisionally induced dissociation. Data were analyzed with Mascot 2.4 (Matrix Science) and Peaks 7.0 (Bioinformatics Solutions, Inc.) using the custom Lv RNASeq database prepared as described below. False discovery rates were adjusted to 1% at the peptide level using Scaffold 4.3 (Proteome Software). The amino acid sequences of proteins from which peptides were confidently identified were searched using BLAST (39 (link)) against the nonredundant protein database “nr” to find homologous proteins in other organisms.