title: Inhibition of bacteriophage m13 replication with esterified milk proteins.
abstract: Esterified milk proteins [methylated (Met) or ethylated (Et) alpha-lactalbumin (ALA), beta-lactoglobulin (BLG), and beta-casein (BCN)], unmodified native milk proteins, and native basic proteins (calf thymus histone and hen egg white lysozyme) were tested for their antiviral activity against the bacteriophage M13 and for their influence on its replication (except BCN). All esterified milk proteins showed an antiviral activity against the bacteriophage M13, proportional to the extent of esterification and, hence, to the increased basicity of the modified proteins. Antiviral activity of 100% Met-BLG disappeared after its pepsinolysis but not after its trypsinolysis. The antiviral activity of Met-BLG was much higher than that of native basic proteins (histone and lysozyme). One hundred percent Met-BLG and 73% Et-BLG inhibited the replication of bacteriophage M13 completely, whereas 60% Met-ALA inhibited phage replication partially. Calf thymus histone inhibited the replication of bacteriophage M13 at a lower extent (20%) than Met- and Et-BLG (100% inhibition). Protein concentration, pH, and concentration of the Escherichia coli culture in the preincubation medium of the virus were other factors influencing antiviral activity. Interactions of esterified proteins with the phage DNA (phenol extracted) followed the same pattern as observed during studies of the inhibition of the phage replication: Met-BLG > Et-BLG > or = Met-ALA.
authors.affiliation: Institut National de la Recherche Agronomique, Biopolymères, Interactions, Assemblages, Fonctions et Interactions des Protéines Laitières, B.P. 71627, 44316 Nantes Cedex 3, France.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Sitohy
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Chobert
authors.forename: Urszula
authors.initials: U
authors.lastname: Karwowska
authors.forename: Anna
authors.initials: A
authors.lastname: Gozdzicka-Jozefiak
authors.forename: Thomas
authors.initials: T
authors.lastname: Haertlé
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D017104:Bacteriophage M13 / Q000187:drug effects* / Q000502:physiology; D002364:Caseins / Q000737:chemistry / Q000494:pharmacology; D002417:Cattle; D004951:Esterification; D006657:Histones / Q000494:pharmacology; D007768:Lactalbumin / Q000737:chemistry / Q000494:pharmacology; D007782:Lactoglobulins / Q000737:chemistry / Q000494:pharmacology; D008745:Methylation; D008894:Milk Proteins / Q000737:chemistry / Q000494:pharmacology*; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D000998:Antiviral Agents; D002364:Caseins; D006657:Histones; D007782:Lactoglobulins; D008894:Milk Proteins; D007768:Lactalbumin