PMID- 30954451 OWN - NLM STAT- MEDLINE DCOM- 20190923 LR - 20190923 IS - 1879-3150 (Electronic) IS - 0041-0101 (Linking) VI - 164 DP - 2019 Jun TI - Venom composition of adult Western Diamondback Rattlesnakes (Crotalus atrox) maintained under controlled diet and environmental conditions shows only minor changes. PG - 51-60 LID - S0041-0101(19)30112-6 [pii] LID - 10.1016/j.toxicon.2019.03.027 [doi] AB - Many species of snakes produce venom as a chemical means of procuring potentially fractious prey. Studies have increasingly focused on venom compositional variation between and within individual snakes of the same species/subspecies, with significant differences often being observed. This variation in composition has been attributed to differences in age, season, diet, and environment, suggesting that these factors could help explain the inter- and intra-specific variation found in some snake venoms, perhaps via some type of feedback mechanism(s). To address several of these possible sources of variation, this study utilized wild-caught Western Diamondback Rattlesnakes (Crotalus atrox) from Cochise Co., AZ. Sixteen adult C. atrox were maintained in the lab on a diet of NSA mice for eight months to determine whether venom composition changed in captivity under a static diet in a stable environment. Reducing 1-D SDS-PAGE, fibrinogen degradation assays, reversed-phase HPLC, and MALDI-TOF mass spectrometry revealed only minor differences over time within individuals. Venom L-amino acid oxidase (LAAO) and phosphodiesterase activities significantly increased over the course of captivity, with no changes occurring in azocasein metalloproteinase, kallikrein-like serine proteinase (KLSP), or thrombin-like serine proteinase (TLSP) activities. Snake total length was positively correlated with TLSP activity and negatively correlated with LAAO and KLSP activity. There was typically a much higher degree of variation between individuals than within individuals for all analyses performed and measurements collected. Because the overall "fingerprint" of each snake's venom remained more/less constant, it is concluded that biologically significant changes in venom composition did not occur within individual C. atrox as a function of captivity/diet. However, this study does indicate that differences in activity levels do occur in minor venom enzyme components, but the differences observed are likely to be of minimal significance to the production of antivenom or to subsequent treatment of human envenomations. CI - Copyright (c) 2019 Elsevier Ltd. All rights reserved. FAU - Rex, Christopher J AU - Rex CJ AD - Department of Biological Sciences, 501 20th St., University of Northern Colorado, Greeley, CO, 80639-0017, USA. FAU - Mackessy, Stephen P AU - Mackessy SP AD - Department of Biological Sciences, 501 20th St., University of Northern Colorado, Greeley, CO, 80639-0017, USA. Electronic address: stephen.mackessy@unco.edu. LA - eng PT - Journal Article DEP - 20190404 PL - England TA - Toxicon JT - Toxicon : official journal of the International Society on Toxinology JID - 1307333 RN - 0 (Crotalid Venoms) RN - 9001-32-5 (Fibrinogen) SB - IM MH - Animals MH - Body Size MH - Chromatography, High Pressure Liquid MH - Crotalid Venoms/*chemistry MH - Crotalus/*physiology MH - Diet/*veterinary MH - Electrophoresis, Polyacrylamide Gel MH - Female MH - Fibrinogen/metabolism MH - Humans MH - Male MH - Mass Spectrometry MH - Mice OTO - NOTNLM OT - Diet OT - Enzyme toxins OT - Snake venom OT - Variation EDAT- 2019/04/08 06:00 MHDA- 2019/09/24 06:00 CRDT- 2019/04/08 06:00 PHST- 2019/02/26 00:00 [received] PHST- 2019/03/26 00:00 [revised] PHST- 2019/03/31 00:00 [accepted] PHST- 2019/04/08 06:00 [pubmed] PHST- 2019/09/24 06:00 [medline] PHST- 2019/04/08 06:00 [entrez] AID - S0041-0101(19)30112-6 [pii] AID - 10.1016/j.toxicon.2019.03.027 [doi] PST - ppublish SO - Toxicon. 2019 Jun;164:51-60. doi: 10.1016/j.toxicon.2019.03.027. Epub 2019 Apr 4.