Biomaterial Database

Isolation of a pyrazine alarm pheromone component from the fire ant, Solenopsis invicta. 2010

Robert K Vander Meer, and Catherine A Preston, and Man-Yeon Choi

CMAVE, ARS, USDA, 1600 SW 23rd Drive, Gainesville, FL 32608, USA. bob.vandermeer@ars.usda.gov

Alarm pheromones in social insects are an essential part of a complex of pheromone interactions that contribute to the maintenance of colony integrity and sociality. The alarm pheromones of ants were among the first examples of animal pheromones identified, primarily because of the large amount of chemical produced and the distinctive responses of ants to the pheromone. However, the alarm pheromone of the fire ant, Solenopsis invicta, eluded identification for over four decades. We identified 2-ethyl-3,6-dimethylpyrazine as an alarm pheromone component of S. invicta. Worker fire ants detect the pyrazine alarm pheromone at 30 pg/ml, which is comparable to alarm pheromone sensitivities reported for other ant species. The source of this alarm pheromone are the mandibular glands, which, in fire ants, are not well developed and contain only about 300 pg of the compound, much less than the microgram quantities of alarm pheromones reported for several other ant species. Female and male sexuals and workers produce the pyrazine, which suggests that it may be involved in fire ant mating flight initiation, as well as the typical worker alarm response. This is the first report of 2-ethyl-3,6-dimethylpyrazine from a Solenopsis species and the first example of this alkaloid functioning as an alarm pheromone.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D010675	Pheromones	Chemical substances, excreted by an organism into the environment, that elicit behavioral or physiological responses from other organisms of the same species. Perception of these chemical signals may be olfactory or by contact.	Allelochemical,Allelochemicals,Allomone,Allomones,Ectohormones,Kairomone,Kairomones,Pheromone,Semiochemical,Semiochemicals,Synomones
D011719	Pyrazines	A heterocyclic aromatic organic compound with the chemical formula C4H4N2.	Pyrazine
D005260	Female		Females
D000042	Absorption	The physical or physiological processes by which substances, tissue, cells, etc. take up or take in other substances or energy.
D000470	Alkaloids	Organic nitrogenous bases. Many alkaloids of medical importance occur in the animal and vegetable kingdoms, and some have been synthesized. (Grant & Hackh's Chemical Dictionary, 5th ed)	Alkaloid,Plant Alkaloid,Plant Alkaloids,Alkaloid, Plant,Alkaloids, Plant
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001000	Ants	Insects of the family Formicidae, very common and widespread, probably the most successful of all the insect groups. All ants are social insects, and most colonies contain three castes, queens, males, and workers. Their habits are often very elaborate and a great many studies have been made of ant behavior. Ants produce a number of secretions that function in offense, defense, and communication. (From Borror, et al., An Introduction to the Study of Insects, 4th ed, p676)	Ant
D001522	Behavior, Animal	The observable response an animal makes to any situation.	Autotomy Animal,Animal Behavior,Animal Behaviors
D014835	Volatilization	A phase transition from liquid state to gas state, which is affected by Raoult's law. It can be accomplished by fractional distillation.	Vaporization,Volatility