Chitin binding motif

Fig. 18 CG15920 gene sequence and primary structure. The consensus repeat sequences are also represented. The highlighted regions correspond to the signal sequence, R R chitin-binding domain, and the elastomeric domains containing repeat motifs A and B. Reproduced from [182, 188] with permission from Elsevier, copyright Elsevier 2001, 2010...

The arsenal of plant defense peptides contains members capable of binding carbohydrate residues, namely /31-4 linked A -acetyl glucosamine residues that form the biopolymer chitin. The actual mode of action remains unclear. Antifungal and antimicrobial activity has been shown in vitro. For example Ac-AMP2 is a small disulfide-rich chitin-binding peptide isolated from the seeds of Amaranthus caudatus with antimicrobial activity. It differs from Ac-AMP 1 by one additional arginine residue at the C-terminus. The structure was determined by NMR and contains a cystine knot motif. Ac-AMP2 displays a so-called hevein domain partly... 

T. Suetake, S. Tsuda, S. Kawabata, K. Miura, S. Iwanaga, K. Hikichi, K. Nitta, and K. Kawano, Chitin-binding proteins in invertebrates and plants comprise a common chitin-bind-ing structural motif, J. Biol. Chem., 275 (2000) 17929-17932. 

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