Calgene Fresh, a wholly owned subsidiary of Calgene Inc., andAgritope, a division of Epitope Inc. of Beaverton, Ore.,announced last week that they will exchange their respectiveproprietary technologies for ethylene regulation in crops.

Researchers have shown that it's possible to affect the ripeningof fresh-market produce such as tomatoes by manipulating theplant's own biochemical pathway for ethylene biosynthesis. (Infact, wholesalers spray ethylene gas on rock-hard greentomatoes to ripen them artificially before they appear ongrocer's shelves.)

Ethylene is synthesized from methionine via S-adenosylmethionine (SAM) and 1-aminocyclopropane-1-carboxylic acid (ACC), catalyzed by ACC synthase. It's possibleto interfere with this pathway by preventing the formation ofACC -- either by blocking the activity of ACC synthase per se orby catalyzing the cleavage of ACC by ACC deaminase (ACCD) --or by degrading SAM via SAM hydrolase.

Calgene Fresh of Evanston, Ill., is providing its ACC deaminase(ACCD) for Agritope's ongoing studies of ethylene regulation inraspberries. In return, Calgene Fresh gets Agritope's SAMhydrolase to use in tomato research and in field trials.

"By sharing our technologies, we will be capable of developinga broad array of superior fresh fruit and vegetable productswhich meet consumer demand," said William Hiatt, CalgeneFresh's vice president of research and development.

Calgene's stock (NASDAQ:CGNE) closed unchanged Friday at$13.75 a share, while Epitope (ASE:EPT) shares gained 13 cents,closing Friday at $16.75.

-- Jennifer Van Brunt Senior Editor

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