title: A novel lectin from Agrocybe aegerita shows high binding selectivity for terminal N-acetylglucosamine.
abstract: A novel lectin was isolated from the mushroom Agrocybe aegerita (designated AAL-2) by affinity chromatography with GlcNAc (N-acetylglucosamine)-coupled Sepharose 6B after ammonium sulfate precipitation. The AAL-2 coding sequence (1224 bp) was identified by performing a homologous search of the five tryptic peptides identified by MS against the translated transcriptome of A. aegerita. The molecular mass of AAL-2 was calculated to be 43.175 kDa from MS, which was consistent with the data calculated from the amino acid sequence. To analyse the carbohydrate-binding properties of AAL-2, a glycan array composed of 465 glycan candidates was employed, and the result showed that AAL-2 bound with high selectivity to terminal non-reducing GlcNAc residues, and further analysis revealed that AAL-2 bound to terminal non-reducing GlcNAc residues with higher affinity than previously well-known GlcNAc-binding lectins such as WGA (wheatgerm agglutinin) and GSL-II (Griffonia simplicifolia lectin-II). ITC (isothermal titration calorimetry) showed further that GlcNAc bound to AAL-2 in a sequential manner with moderate affinity. In the present study, we also evaluated the anti-tumour activity of AAL-2. The results showed that AAL-2 could bind to the surface of hepatoma cells, leading to induced cell apoptosis in vitro. Furthermore, AAL-2 exerted an anti-hepatoma effect via inhibition of tumour growth and prolongation of survival time of tumour-bearing mice in vivo.
authors.affiliation: College of Life Sciences, Wuhan University, Wuhan 430072, People's Republic of China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Jiang
authors.forename: Yijie
authors.initials: Y
authors.lastname: Chen
authors.forename: Man
authors.initials: M
authors.lastname: Wang
authors.forename: Yalin
authors.initials: Y
authors.lastname: Yin
authors.forename: Yongfu
authors.initials: Y
authors.lastname: Pan
authors.forename: Bianli
authors.initials: B
authors.lastname: Gu
authors.forename: Guojun
authors.initials: G
authors.lastname: Yu
authors.forename: Yamu
authors.initials: Y
authors.lastname: Li
authors.forename: Barry Hon Cheung
authors.initials: BH
authors.lastname: Wong
authors.forename: Yi
authors.initials: Y
authors.lastname: Liang
authors.forename: Hui
authors.initials: H
authors.lastname: Sun
mesh_terms: D000117:Acetylglucosamine / Q000378:metabolism*; D055362:Agrocybe / Q000378:metabolism*; D000595:Amino Acid Sequence; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy / Q000473:pathology; D045744:Cell Line, Tumor; D005656:Fungal Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000627:therapeutic use; D006801:Humans; D037102:Lectins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000627:therapeutic use; D008113:Liver Neoplasms / Q000188:drug therapy / Q000473:pathology; D008969:Molecular Sequence Data; D011485:Protein Binding; D023041:Xenograft Model Antitumor Assays
chemical_list: D005656:Fungal Proteins; D037102:Lectins; D000117:Acetylglucosamine