title: Rhamnolipid-biosurfactant permeabilizing effects on gram-positive and gram-negative bacterial strains.
abstract: The potential of biosurfactant PS to permeabilize bacterial cells of Pseudomonas aeruginosa, Escherichia coli, and Bacillus subtilis on growing (in vivo) and resting (in vitro) cells was studied. Biosurfactant was shown to have a neutral or detrimental effect on the growth of Gram-positive strains, and this was dependent on the surfactant concentration. The growth of Gram-negative strains was not influenced by the presence of biosurfactant in the media. Cell permeabilization with biosurfactant PS was shown to be more effective with B. subtilis resting cells than with Pseudomonas aeruginosa. Scanning-electron microscopy observations showed that the biosurfactant PS did not exert a disruptive action on resting cells such that it was detrimental to the effect on growing cells of B. subtilis. Low critical micelle concentrations, tender action on nongrowing cells, and neutral effects on the growth of microbial strains at low surfactant concentrations make biosurfactant PS a potential candidate for application in different industrial fields, in environmental bioremediation, and in biomedicine.
authors.affiliation: Department of Microbial Biochemistry and Biosynthesis, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria.
authors.forename: A V
authors.initials: AV
authors.lastname: Sotirova
authors.forename: D I
authors.initials: DI
authors.lastname: Spasova
authors.forename: D N
authors.initials: DN
authors.lastname: Galabova
authors.forename: E
authors.initials: E
authors.lastname: Karpenko
authors.forename: A
authors.initials: A
authors.lastname: Shulga
mesh_terms: D000464:Alginates / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development / Q000648:ultrastructure; D020723:Glucuronic Acid / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D006017:Glycolipids / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D006603:Hexuronic Acids / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D008855:Microscopy, Electron, Scanning; D010539:Permeability; D011549:Pseudomonas / Q000737:chemistry / Q000378:metabolism*; D012988:Soil Microbiology; D013501:Surface-Active Agents / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D000464:Alginates; D006017:Glycolipids; D006603:Hexuronic Acids; D013501:Surface-Active Agents; C418382:rhamnolipid; D020723:Glucuronic Acid