About the Lectin

Crude extracts of avocado seeds contain a protein that exhibits lectin-like activity 1 , similar to that found in mango. The crude material does not agglutinate normal human erythrocytes, but it does agglutinate a number of micro-organisms. PAA agglutinates Streptococcus mutans 1 , and has been shown to reduce the adhesion of S. mutans to tooth surfaces 2 . PAA also agglutinates several strains of Campylobacter jejuni and Campylobacter coli 3 , and many different strains of Legionella 4 , but is reactive with only one strain of Listeria monocytogenes 5 . Little is known about the specificity of PAA, however, desialylated erythrocytes are agglutinated by the lectin while untreated cells are not, indicating that the terminal sialic acid masks the lectin binding site. PAA is only available in crude form.


  1. Meade, N. A., et al. (1980) Carbohydr. Res. 78 : 349-363.
  2. Staat, R. H., et al. (1980) Infect. Immunol. 27 : 675-681.
  3. Staat, R. H., et al. (1978) Adv. Exp. Med. Biol. 107 : 639-647.
  4. Doyle, R. J., et al. (1982) J. Clin. Micro. 15 : 973-975.
  5. Slifkin, M. and Doyle, R.J. (1990) Clin. Micro. Rev. 3 : 197-218.

Product Characteristics

Buffer 0.01M Phosphate – 0.15M NaCl, pH 7.2-7.4.
Blood Group Not reactive with normal human cells
Activity Less than 1 mg/ml of the crude lectin will agglutinate neuraminidase treated human erythrocytes.
Inhibitory Carbohydrate Not determined.