title: Broad spectrum antimicrobial activity of leukocyte extracts from the American alligator (Alligator mississippiensis).
abstract: Leukocytes were isolated from whole blood of wild alligators by differential sedimentation. The leukocytes were disrupted in 5% AcOH and the crude extracts processed by ultrafiltration. The extracts were subjected to solvent exchange (0.1% AcOH) and the fraction that contained macromolecules between 1 and 10 kDa were subjected to further analyses. The acid extracts of the alligator leukocytes exhibited substantial antimycotic activities against six of eight species of Candida yeast tested. In addition, the alligator leukocyte extracts were effective as antimicrobial agents against 10 of 12 bacterial species, and displayed moderate activity against two enveloped viruses (human immunodeficiency virus-1 and herpes simplex virus-1(HF)). Kinetic analyses revealed that the antimycotic effects of the leukocyte extract occurred rapidly, with 64% fungal growth inhibition within 3 min of exposure. The molecule(s) responsible for the antimicrobial activities were sensitive to proteases, heat-stable, acid soluble, and in the 1-10 kDa range. These data suggest that alligator leukocytes express cationic peptides that are responsible for their antimicrobial properties.
authors.affiliation: Department of Chemistry, McNeese State University, Lake Charles, Box 90455, LA 70609, USA. mmerchan@mcneese.edu
authors.forename: Mark E
authors.initials: ME
authors.lastname: Merchant
authors.forename: Noelle
authors.initials: N
authors.lastname: Leger
authors.forename: Erin
authors.initials: E
authors.lastname: Jerkins
authors.forename: Kaili
authors.initials: K
authors.lastname: Mills
authors.forename: Melanie B
authors.initials: MB
authors.lastname: Pallansch
authors.forename: Robin L
authors.initials: RL
authors.lastname: Paulman
authors.forename: Roger G
authors.initials: RG
authors.lastname: Ptak
mesh_terms: D000489:Alligators and Crocodiles / Q000276:immunology*; D000818:Animals; D000890:Anti-Infective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D002175:Candida / Q000187:drug effects; D002457:Cell Extracts / Q000276:immunology* / Q000494:pharmacology*; D006678:HIV / Q000187:drug effects; D018259:Herpesvirus 1, Human / Q000187:drug effects; D007962:Leukocytes / Q000737:chemistry*; D013997:Time Factors
chemical_list: D000890:Anti-Infective Agents; D002457:Cell Extracts