A gene encoding a hevein-like protein from elderberry fruits is homologousto PR-4 and class V chitinase genes

We isolated SN-HLPf (Sambucus nigra hevein-like fruit protein), a hevein-li ke chitin-binding protein, from mature elderberry fruits. Cloning of the co rresponding gene demonstrated that SN-HLPf is synthesized as a chimeric pre cursor consisting of an N-terminal chitin-binding domain corresponding to t he mature elderberry protein and an unrelated C-terminal domain. Sequence c omparisons indicated that the N-terminal domain of this precursor has high sequence similarity with the N-terminal domain of class I PR-4 (pathogenesi s-related) proteins, whereas the C terminus is most closely related to that of class V chitinases. On the basis of these sequence homologies the gene encoding SN-HLPf can be considered a hybrid between a PR-4 and a class V ch itinase gene.