Individual variability in Tityus serrulatus (Scorpiones, Buthidae) venom elicited by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Venom variability in specimens of Tityus serrulatus scorpion was assessed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) analyses. An expanded time lag venom extraction protocol was carried out using ten scorpions to study individual variations that might occur due to different rates in protein expression and/or processing. The first extraction of venom was made from the animals after 20 days of starvation, which allowed the venom gland to be filled up. The second extraction event was carried out 24 hours after the first one. The third was 8 days after the first extraction. By means of MALDI-TOF analyses, important variations were observed in venoms of a single specimen extracted at different times, especially in latter extraction events. These variations are most probably related to dynamics in cell gland production. Since T. serrulatus is a parthenogenetic species, sexual variations are naturally excluded and we did not expect intra-specific variations, which was confirmed. Knowledge of individual venom variability is extremely important to avoid misunderstandings in the use of venom proteomic analysis as a taxonomic tool.