title: Structurally dissimilar proteins with antiviral and antifungal potency from cowpea (Vigna unguiculata) seeds.
abstract: Evidence is presented for the existence of multiple proteins with antifungal and antiviral potency in cowpea seeds. The two proteins, designated alpha- and beta-antifungal proteins in accordance with their order of elution from the CM-Sepharose column, were capable of inhibiting human immunodeficiency virus (HIV) reverse transcriptase and one of the glycohydrolases associated with HIV infection, alpha-glucosidase, but beta-glucuronidase was not repressed. The ability of the proteins in retarding mycelial growth of a variety of fungi was also demonstrated with alpha-antifungal protein being more potent in most of the cases. Beta-antifungal protein was more active in only one instance. Both antifungal proteins had low cell-free translation-inhibitory activity. The proteins were adsorbed on Affi-gel blue gel-and CM-Sepharose but could be separated from one another during chromatography on the latter medium by means of a linear NaCl concentration gradient. Different molecular weights were exhibited by the proteins, being 28 kDa and 12 kDa respectively for alpha- and beta- antifungal proteins. Alpha-antifungal protein was characterized by an N-terminal sequence showing close resemblance to sequences of chitinases. Beta-antifungal protein exhibited an N-terminal sequence hitherto unknown in the literature.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, NT.
authors.forename: X Y
authors.initials: XY
authors.lastname: Ye
authors.forename: H X
authors.initials: HX
authors.lastname: Wang
authors.forename: T B
authors.initials: TB
authors.lastname: Ng
mesh_terms: D000595:Amino Acid Sequence; D019380:Anti-HIV Agents / Q000737:chemistry / Q000494:pharmacology*; D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology*; D007887:Fabaceae / Q000737:chemistry*; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors*; D015497:HIV-1 / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000494:pharmacology*; D010946:Plants, Medicinal; D011487:Protein Conformation; D018894:Reverse Transcriptase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D012639:Seeds / Q000737:chemistry
chemical_list: D019380:Anti-HIV Agents; D000935:Antifungal Agents; D010940:Plant Proteins; D018894:Reverse Transcriptase Inhibitors; D054303:HIV Reverse Transcriptase