Beamlok model 2080 kv

Resonance Raman spectra were recorded using a Raman spectrometer consisting of a Spex model 1877 triple spectrograph and a charge-coupled device (CCD) detector as reported previously [17 (link)]. A 406.7 nm line from an argon-krypton ion laser (Spectra-Physics BeamLok model 2080-KV) was used as the excitation source, and the Raman signal was collected in a 120° geometry. The laser power was adjusted to ~5 mW at the sample. Each spectrum was recorded with a 60 s accumulation time, and 10 repetitively measured spectra were averaged to improve the quality of the final spectrum. The frequencies of the Raman bands were calibrated using the standard spectrum of cyclohexane. Samples contained 0.2 mM MauG in 0.05 M phosphate buffer, pH 7.5, with 10% ethylene glycol either with or without 0.1 mM PreMADH. The ν₃ bands were deconvoluted by the peak searching and fitting function of the LabSpec software provided with the CCD detector (Horiba Instruments) using a combination of the Gaussian and Lorentzian functions.

Resonance Raman spectra were recorded using a Raman spectrometer consisting of a Spex model 1877 triple spectrograph and a CCD detector as reported previously [26 (link)]. A 406.7 nm line from an argon-krypton ion laser (Spectra-Physics BeamLok model 2080-KV) was used as the excitation source, and the Raman signal was collected in a 120° geometry. The laser power was adjusted to ~5 mW at the sample. Each spectrum was recorded with a 60 s accumulation time, and 10 repetitively measured spectra were averaged to improve the quality of the final spectrum. The frequencies of the Raman bands were calibrated using the standard spectrum of cyclohexane. Samples contained 0.15 mM protein in 0.05 M potassium phosphate buffer, pH 7.5, and spectra were recorded at 25 °C.