title: Effect of heterogeneity of hydrophobic moieties on surface activity of lichenysin A, a lipopeptide biosurfactant from Bacillus licheniformis BAS50.
abstract: Lichenysin A, a surface-active lipopeptide produced by Bacillus licheniformis, strain BAS50, contains longchain beta-hydroxy fatty acids. Regulation of the synthesis of fatty acids and beta-hydroxy fatty acids was studied by modifying the culture medium. Addition of branched-chain alpha-amino acids to the medium caused similar changes to both cellular fatty acid and to beta-hydroxy fatty acid composition in the lipophilic part of lichenysin A. Production of lichenysin A was enhanced about two- and four-fold by addition of L-glutamic acid and L-asparagine respectively. It is suggested that these amino acids may be involved in the control of lipopeptide formation. Elucidation of the structure-function relationship of surface-active lipopeptides by analysis of the activities of structurally characterized compounds is discussed. Fractions of lichenysin A with branched beta-hydroxy acids in the lipid tail demonstrated lower surface-tension activity than the fractions of lichenysin A having straight beta-hydroxy acids. The presence of a lichenysin A fraction with beta-hydroxymyristic [(C14)n] acid residues appears to have an important influence on the surface activity of a mixture of lichenysins A.
authors.affiliation: Division of Microbiology, GBF National Research Centre for Biotechnology, Braunschweig, Federal Republic of Germany.
authors.forename: M M
authors.initials: MM
authors.lastname: Yakimov
authors.forename: H L
authors.initials: HL
authors.lastname: Fredrickson
authors.forename: K N
authors.initials: KN
authors.lastname: Timmis
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000494:pharmacology*; D001407:Bacillus / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism; D003470:Culture Media; D008074:Lipoproteins / Q000096:biosynthesis / Q000737:chemistry*; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000096:biosynthesis / Q000737:chemistry*; D012995:Solubility; D013329:Structure-Activity Relationship; D013501:Surface-Active Agents / Q000737:chemistry* / Q000378:metabolism; D014867:Water / Q000737:chemistry
chemical_list: D000596:Amino Acids; D003470:Culture Media; D008074:Lipoproteins; D010456:Peptides, Cyclic; D013501:Surface-Active Agents; C094325:lichenysin A; D014867:Water