S. Mayfield et al., Limitation and failure of immunological technique (ELISA) in resolving thediet of the South African rock lobster Jasus lalandii, MARINE BIOL, 137(4), 2000, pp. 595-604
Declines in rock-lobster (Jasus lalandii) growth have prompted a re-assessm
ent of their diet, for which we employed an immunological approach (enzyme-
linked immunosorbent assay, ELISA). Antisera were raised against 26 prey sp
ecies, and their specificity was determined using ELISA. Antibody-binding w
as compared using Western blots. The antisera showed high specificity to un
digested prey with cross-reactions among antisera being reduced to < 4%. Ho
wever, crossreactivity increased to 49% when tested against digested prey,
with some antisera even failing to recognise homologous prey. Sodium dodecy
lsulphate (SDS) gel electrophoresis demonstrated that excess rock-lobster d
igestive enzymes prevented the identification of digested prey by ELISA. Ho
wever, "inhibition ELISA" (modified ELISA) did demonstrate species-specific
proteins in the digested extracts and could be used to identify digested p
rey accurately. Nevertheless, the problem of enzyme interference has to be
solved before large-scale screening of rock-lobster diets by ELISA is feasi
ble.