Cys/Gly-rich proteins with a putative single chitin-binding domain from oat (Avena sativa) seeds.
Through a reliable and repeatable procedure based on solid-phase extraction techniques, a protein fraction (P fraction) rich in Cys/Gly residues was extracted and captured from oat (Avena sativa L.) seeds. Quantitative amino acid analysis and MS of the P fraction indicated that it contains a series of heterogeneous Cys/Gly-rich proteins with molecular masses of 3.6-4.0 kDa. Preliminary results from bioassays showed that these proteins possess weak to moderate antifungal properties to some fungal strains. From this fraction, a new polypeptide, designated avesin A, was purified and sequenced by Edman degradation. Avesin A consists of 37 amino-acid residues, with 10 glycine residues and eight cysteine residues forming disulfide bridges, and contains a single chitin-binding domain, which indicates that avesin A is a new member of the putative chitin-binding proteins. Avesin A is the first identified hevein-like small protein from cereal grains.
Division of Pharmacognosy, Department of Medicinal Chemistry, Biomedical Center, PO Box 574, Uppsala University, SE-751 23, Uppsala, Sweden. rockylee86@yahoo.com
Shi-Sheng
SS
Li
Per
P
Claeson
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000935:Antifungal Agents / Q000737:chemistry; D018554:Avena / Q000737:chemistry*; D002686:Chitin / Q000378:metabolism*; D003545:Cysteine / Q000737:chemistry; D004220:Disulfides / Q000032:analysis / Q000737:chemistry; D005998:Glycine / Q000737:chemistry; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology; D017434:Protein Structure, Tertiary; D012639:Seeds / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D000596:Amino Acids; D000935:Antifungal Agents; D004220:Disulfides; D010940:Plant Proteins; D002686:Chitin; D003545:Cysteine; D005998:Glycine