Mass spectrometry data and size exclusion chromatography profiles of Australian taipan venom toxins

Abstract

The compositions of paradoxin and taipoxin (PDx and TPx, respectively) were investigated using size exclusion chromatography (SEC) and nano-electrospray ionization mass spectrometry (nano-ESI-MS). The elution profiles from size exclusion chromatography of the venoms from Oxyuranus microlepidotus and Oxyuranus scutellatus were similar. Fractions corresponding to the trimeric toxins were treated with guanidinium hydrochloride and the individual subunits were separated by HPLC. In this report we present the size exclusion chromatography profiles for these toxins, and the nano-ESI mass spectra of the subunits after separation by HPLC: the first such comparative study of these toxins at the protein level. Data in this article are associated with the research article published in Toxicon: "Insight into the subunit arrangement and diversity of paradoxin and taipoxin" (J.A. Harrison, J.A. Aquilina, 2016) [1].

Fig. 1

Separation of ~45 kDa toxins from Oxyuranus spp. whole venom via SEC. Chromatograms show the constituents of O. microlepidotus (A) and O. scutellatus (B) whole venom which where partitioned by SEC. Each of the individual SEC peaks were numbered in order of elution, and those peaks previously reported to contain PDx and TPx are marked with an asterisk , , . The molecular weight of each marker band is given in kDa.

Fig. 2

Mass spectra of PDx subunits separated by HPLC . Spectra exhibit multiple charge states. The spectrum from the first HPLC peak (Figure 5 in [1]) for PDx (a) shows a charge state series between m/z 1750 and 2800 while the second HPLC peak (Figure 5 in [1]), (b) shows two series of charge states between m/z 1750 and 3350. The subunit identity of each series is shown above the peaks (α, β, and γ).

Fig. 3

Mass spectra of TPx subunits separated by HPLC . For HPLC peaks one to four (Fig. 5 in [1]), charge state series were evident between 1800 and 2750 m/z, while peak 5 (Figure 5 in [1]) contained components with charge states arising within a higher m/z window. Each inset shows the mass distribution of β_TPx isoforms for relevant HPLC peaks. The subunit identified by each series is shown on the top of each spectra.