title: Comparative studies of the venom of a new Taipan species, Oxyuranus temporalis, with other members of its genus.
abstract: Taipans are highly venomous Australo-Papuan elapids. A new species of taipan, the Western Desert Taipan (Oxyuranus temporalis), has been discovered with two specimens housed in captivity at the Adelaide Zoo. This study is the first investigation of O. temporalis venom and seeks to characterise and compare the neurotoxicity, lethality and biochemical properties of O. temporalis venom with other taipan venoms. Analysis of O. temporalis venom using size-exclusion and reverse-phase HPLC indicated a markedly simplified "profile" compared to other taipan venoms. SDS-PAGE and agarose gel electrophoresis analysis also indicated a relatively simple composition. Murine LD50 studies showed that O. temporalis venom is less lethal than O. microlepidotus venom. Venoms were tested in vitro, using the chick biventer cervicis nerve-muscle preparation. Based on t90 values, O. temporalis venom is highly neurotoxic abolishing indirect twitches far more rapidly than other taipan venoms. O. temporalis venom also abolished responses to exogenous acetylcholine and carbachol, indicating the presence of postsynaptic neurotoxins. Prior administration of CSL Taipan antivenom (CSL Limited) neutralised the inhibitory effects of all taipan venoms. The results of this study suggest that the venom of the O. temporalis is highly neurotoxic in vitro and may contain procoagulant toxins, making this snake potentially dangerous to humans.
authors.affiliation: Monash Venom Group, Department of Pharmacology, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria 3168, Australia. carmel.barber@monash.edu.
authors.forename: Carmel M
authors.initials: CM
authors.lastname: Barber
authors.affiliation: Venom Science Pty Ltd, Tanunda, South Australia 5352, Australia. frankmadaras@esc.net.au.
authors.forename: Frank
authors.initials: F
authors.lastname: Madaras
authors.affiliation: SA Pathology, IMVS Veterinary Services, Gilles Plains, South Australia 5086, Australia. randcturnbull@bigpond.com.
authors.forename: Richard K
authors.initials: RK
authors.lastname: Turnbull
authors.affiliation: Adelaide Zoo, Adelaide, South Australia 5000, Australia. tmorley@zoossa.com.au.
authors.forename: Terry
authors.initials: T
authors.lastname: Morley
authors.affiliation: Venom Supplies, Tanunda, South Australia, South Australia 5352, Australia. luke@venomsupplies.com.
authors.forename: Nathan
authors.initials: N
authors.lastname: Dunstan
authors.affiliation: Venom Supplies, Tanunda, South Australia, South Australia 5352, Australia. nathan@venomsupplies.com.
authors.forename: Luke
authors.initials: L
authors.lastname: Allen
authors.affiliation: SA Pathology, IMVS Veterinary Services, Gilles Plains, South Australia 5086, Australia. tim.kuchel@sahmri.com.
authors.forename: Tim
authors.initials: T
authors.lastname: Kuchel
authors.affiliation: Venom Science Pty Ltd, Tanunda, South Australia 5352, Australia. peter@venomsupplies.com.
authors.forename: Peter
authors.initials: P
authors.lastname: Mirtschin
authors.affiliation: Monash Venom Group, Department of Pharmacology, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria 3168, Australia. wayne.hodgson@monash.edu.
authors.forename: Wayne C
authors.initials: WC
authors.lastname: Hodgson
mesh_terms: D000818:Animals; D000997:Antivenins / Q000494:pharmacology; D002645:Chickens; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D004546:Elapid Venoms / Q000737:chemistry / Q000633:toxicity*; D017815:Elapidae; D004591:Electrophoresis, Polyacrylamide Gel; D007928:Lethal Dose 50; D051379:Mice; D009469:Neuromuscular Junction / Q000187:drug effects; D009498:Neurotoxins / Q000737:chemistry / Q000633:toxicity*
chemical_list: D000997:Antivenins; D004546:Elapid Venoms; D009498:Neurotoxins