title: Purification and characterization of a mucin specific mycelial lectin from Aspergillus gorakhpurensis: application for mitogenic and antimicrobial activity.
abstract: BACKGROUND
  Lectins are carbohydrate binding proteins or glycoproteins that bind reversibly to specific carbohydrates present on the apposing cells, which are responsible for their ability to agglutinate red blood cells, lymphocytes, fibroblasts, etc. Interest in lectins has been intensified due to their carbohydrate specificity as they can be valuable reagents for the investigation of cell surface sugars, purification and characterization of glycoproteins. The present study reports the purification, characterization and evaluation of mitogenic and antimicrobial potential of a mycelial lectin from Aspergillus gorakhpurensis.
  
  
  METHODS
  Affinity chromatography on mucin-sepharose column was carried out for purification of Aspergillus gorakhpurensis lectin. The lectin was characterized for physico-chemical parameters. Mitogenic potential of the lectin was evaluated against splenocytes of Swiss albino mice by MTT assay. Antimicrobial activity of the purified lectin has also been evaluated by disc diffusion assay.
  
  
  RESULTS
  Single-step affinity purification resulted in 18.6-fold purification of the mycelial lectin. The molecular mass of the lectin was found to be 70 kDa and it was composed of two subunits of 34.8 kDa as determined by gel filtration chromatography, SDS-PAGE and MALDI-TOF analysis. pH optima of the lectin was found to be 6.5-9.5, while optimum temperature for lectin activity was 20-30 °C. Lectin was stable within a pH range of 7.0-10.5 and showed fair thermostability. EDTA did not affect lectin activity whereas it was found susceptible to the denaturants tested. MTT assay revealed strong mitogenic potential of A. gorakhpurensis lectin at a concentration upto 150 µg/mL. Antimicrobial activity assay showed its potent antibacterial activity against Bacillus cereus, Staphylococcous aureus and Escherichia coli and marginal antifungal activity against Saccharomyces cerevisiae.
  
  
  CONCLUSIONS
  This is the first report on the mitogenic and antimicrobial potential of Aspergillus gorakhpurensis lectin. The results will provide useful guidelines for further research in clinical applications of this lectin.
authors.affiliation: Carbohydrate and Protein Biotechnology Laboratory, Department of Biotechnology, Punjabi University, Patiala, Punjab, India.
authors.forename: Ram Sarup
authors.initials: RS
authors.lastname: Singh
authors.affiliation: Carbohydrate and Protein Biotechnology Laboratory, Department of Biotechnology, Punjabi University, Patiala, Punjab, India.
authors.forename: Hemant Preet
authors.initials: HP
authors.lastname: Kaur
authors.affiliation: Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India.
authors.forename: Jatinder
authors.initials: J
authors.lastname: Singh
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001230:Aspergillus / Q000737:chemistry*; D001419:Bacteria / Q000187:drug effects; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D004492:Edetic Acid / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005658:Fungi / Q000187:drug effects; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007477:Ions; D037102:Lectins / Q000302:isolation & purification* / Q000494:pharmacology*; D008297:Male; D008670:Metals / Q000494:pharmacology; D051379:Mice; D008826:Microbial Sensitivity Tests; D008934:Mitogens / Q000302:isolation & purification / Q000494:pharmacology*; D008970:Molecular Weight; D009077:Mucins / Q000378:metabolism*; D025282:Mycelium / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013154:Spleen / Q000166:cytology / Q000187:drug effects; D013696:Temperature
chemical_list: D000890:Anti-Infective Agents; D007477:Ions; D037102:Lectins; D008670:Metals; D008934:Mitogens; D009077:Mucins; D004492:Edetic Acid