Cross reaction between P-61 sunflower seedlings oleosomal protein band and porcine pancreatic lipase

Abstract

A true triacylglycerol lipase was detected in germinating sunflower (Helianthus annuus L.) seedlings associated to oleosomes. This enzyme that has not yet been identified was partially purified as shown by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE) (10%); two protein bands, P-61 and P-66 of 61 and 66 kDa, were isolated from the active lipase fraction. Polyclonal antibodies (PAbs) directed against each protein band were produced. Only PAbs against sunflower P-61 were able to inhibit the total lipolytic activity of our preparation. Hence, only the P-61 protein carries the sunflower lipase activity. The relationship between a pure porcine pancreatic lipase and the P-61 purified sunflower lipolytic fraction was investigated, leading to the first evidence of cross reaction between the porcine pancreatic lipase and the P-61 sunflower lipase fraction. These results are in agreement with common epitopes to the porcine pancreatic lipase and the sunflower P-61.

Key words: Triacylglycerol lipase, oleosomes, polyclonal antibodies, cross-reactivity, Helianthus annuus L.