Mycogen Corp. and its subsidiary, Parasitix, announced thatthey have discovered protein toxins produced by severalstrains of Bacillus thuringiensis (Bt) that have pesticidalactivity against at least four species of ants.

The announcement is the first public disclosure of resultsgenerated by a 1990 research and development collaborationbetween S.C. Johnson & Son Inc., Mycogen and Parasitix.

"As far as I know, we're the only ones who have found a Btstrain active against the Hymenoptera order (which includesants and wasps)," said Parasitix President Charles J. Dumbrell."Our global patent review tells us we're the only ones pokingaround in this end of the business."

He said a biocontrol product for ants could be on the marketwithin two to three years.

Parasitix, a wholly owned subsidiary of Mycogen, utilizesMycogen's core technology to develop biocontrol products.Parasitix also manages the collaboration with S.C. Johnson.Dumbrell said scientists from Mycogen and Parasitix havescreened more than 150 Bt toxins from Mycogen's collection ofmore than 3,000, searching for activity in particular insects.

"The scientists that work on this develop a sort of sixth sense,"Dumbrell explained. "They can look at the shape andconfiguration of a given strain and then guess whether it mightwork in, say, a nematode or an insect."

Jim May, director of corporate public information at privatelyheld S.C. Johnson, said the total U.S. market for household insectcontrol products (cockroaches, flies and ants) is more than $800million. He said S.C. Johnson, producers of RAID brand insectcontrol products, will commercialize any household biopesticideproduct that results from the discovery. Mycogen could alsopursue on its own any crop protection applications the newstrains might have.

"This discovery is a validation that there appears to bepotential for Bt in other than the traditional Lepidoptera(caterpillar-type insect) areas," said agricultural biotechnologyanalyst George S. Dahlman, of Piper, Jaffrey & Hopwood inMinneapolis, Minn., who has a "buy" rating on Mycogen stock."And it suggests that there are probably many morediscoveries and opportunities to come," he added.

Bt, a naturally occurring, spore-forming bacterium, isubiquitous, said Leslie Hickle, animal health industrycoordinator for Parasitix. "You can find it anywhere, even in thedust in your office." But although it is harmless to vertebrates,it contains distinctive protein crystals that are toxic to certaininsects.

Once they are ingested by the insect, the proteins produced byBt strains attach to the mucus membrane lining of the digestivetract and cause ulceration, basically leading to starvationand/or massive infection.

Hickle said the company is not disclosing family, genus orspecies information about the ants targeted in their work."Let's just say we targeted the most economically importantspecies of ants," she said.

Philip Ward, a professor of entomology at the University ofCalifornia, Davis, said that several species of ants could beconsidered "economically important," including Linepithemahumile, the so-called Argentine ant, which is a majoragricultural and household pest; Solenopsis invicta, also knownas the fire ant, which forms nests in yards and fields in theSoutheastern U.S.; Monomorium phaoronis, called Pharoah's ant,which nests inside buildings; and finally, several species ofCarpenter ants, which are structural pests.

John McIntyre, vice president of business development andinternational distribution at Ecogen, a competitor of Mycogen indeveloping biocontrol products and technologies, said that themarket for Bt-based products is growing at a clip of 20% peryear. "The continuing discovery of new insecticidally active Btstrains is going to accelerate that growth," he said.

Although work with the active strains has been under way forsix or seven months, according to Dumbrell, Mycogen andParasitix decided to announce the discoveries now because theEuropean patent process makes public all filings six monthsafter they are filed. Mycogen's European patent applicationswill be published in Europe late this month or early in January.The company has already filed for U.S. patents covering thenewly discovered strains.

Mycogen (NASDAQ:MYCO) of San Diego currently has the onlytwo recombinant DNA Bt-based biopesticide products on themarket, MVP and M-Trak. The company holds 34 U.S. patentson its Bt-based products and its bioencapsulation technology.

-- Lisa Piercey Business Editor

(c) 1997 American Health Consultants. All rights reserved.