Antigenic Analysis of Anabaena azollae and the Role of Lectin in The Azolla Anabaena Symbiosis

LADHA, J. K.; WATANABE, I. 1984. Antigenic Analysis of Anabaena azollae and the Role of Lectin in The Azolla Anabaena Symbiosis. New Phytologist, Volume 98 no. 2 p. 295-300

Antigenic cross‐reactivity between symbiotic Anabaena azollae and its Azolla host was detected by an indirect immunofluorescence technique. Antiserum against Anabaena‐free Azolla cell extract cross‐reacted with A. azollae freshly separated from different species of Azolla, but did not cross‐react with any of the free‐living Anabaena species tested, including A. azollae (Newton), which was claimed to be isolated from Azolla.Cell extracts of the whole Azolla‐Anabaena symbiosis and of Anabaena‐free Azolla plants both caused agglutination of human and rabbit erythrocytes whereas extracts of symbiotic A. azollae freshly separated from Azolla plants or free‐living A. azollae (Newton) did not cause haemag‐glutination. Of the several sugars tested α‐D‐galactose inhibited the haemagglutination. Free‐living A. azollae (Newton) showed no cross‐reaction at any growth phase of its life cycle with antiserum against Anabaena‐iree Azolla nor could it bind the haemagglutinating factor from the Azolla‐Anabaena symbiosis.The possible significance of common antigens and lectin in the Azolla‐Anabaena symbiosis is discussed.