title: Enterotoxic, cytotoxic, necrotic and lethal activities in cell-free extracts of Salmonella strains isolated from humans.
abstract: Unconcentrated cell-free sonic extracts from thirty Salmonella strains isolated from the faeces and blood of humans were investigated for the production of enterotoxins in various tests (Vero cell, infant mouse, rabbit skin permeability and rabbit ileal loop), as well as for lethal activity in adult mice. Sonic extracts from 23 (76.7%) strains were lethal for mice, 21 (70%) increased skin permeability and 3 (10%) showed necrotizing activity for the rabbit skin. No Salmonella strain producing typical Escherichia coli toxins, such as thermolabile (LT) or thermostable (STa) enterotoxins, Verotoxin (VT) or cytotoxic necrotizing factor (CNF) cytotoxins, were detected. Non-repetitive fluid accumulation in rabbit loops was obtained when unconcentrated sonic extracts from 10 selected strains were assayed in seven rabbits. Growth of Salmonella in casamino acid yeast extract medium, followed by treatment of bacterial cells with polymyxin B, was demonstrated to be a rapid and sensitive method for releasing the delayed permeability factor.
authors: Departamento de Microbiología y Parasitología, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo, Spain.
authors: E A
authors: EA
authors: González
authors: J
authors: J
authors: Blanco
authors: M
authors: M
authors: Blanco
authors: J I
authors: JI
authors: Garabal
authors: M P
authors: MP
authors: Alonso
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000096:biosynthesis; D001681:Biological Assay; D002522:Chlorocebus aethiops; D003603:Cytotoxins / Q000096:biosynthesis*; D004731:Endotoxins; D004768:Enterotoxins / Q000096:biosynthesis*; D029968:Escherichia coli Proteins; D005243:Feces / Q000382:microbiology; D006460:Hemolysin Proteins / Q000096:biosynthesis; D006801:Humans; D007082:Ileum / Q000382:microbiology; D051379:Mice; D010539:Permeability; D010641:Phenotype; D011817:Rabbits; D012475:Salmonella / Q000378:metabolism / Q000472:pathogenicity*; D012480:Salmonella Infections / Q000382:microbiology*; D018805:Sepsis / Q000382:microbiology; D022622:Shiga Toxin 1; D012867:Skin / Q000378:metabolism / Q000382:microbiology; D013030:Spain; D014709:Vero Cells
chemical_list: D001427:Bacterial Toxins; D003603:Cytotoxins; D004731:Endotoxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins; D022622:Shiga Toxin 1; C027952:salmonella toxin; C027538:heat-labile enterotoxin, E coli