Abstract: Pseudomonas chlororaphis NRRL B-30761 produces monorhamnolipids with predominantly 3-hydroxydodecenoyl-3-hydroxydecanoate (C12:1-C10) or 3-hydroxydodecanoyl-3-hydroxydecanoate (C12-C10) as the lipid moiety under static growth conditions. The cloning and sequencing of three genes and proteins involved in the biosynthesis of monorhamnose-lipid (R1L) is described. Expression of two of these genes, i.e., rhlA and rhlB, together in P. chlororaphis NRRL B-30761 increases R1L production by at least 10-fold. Also the generation of a recombinant P. chlororaphis NRRL B-30761 capable of synthesizing dirhamnose-lipid (R2L) is described. Characterization of R1L and R2L produced by the recombinant P. chlororaphis NRRL B-30761 is also described.

Abstract: Pseudomonas chlororaphis NRRL B-30761 produces monorhamnolipids with predominantly 3-hydroxydodecenoyl-3-hydroxydecanoate (C12:1-C10) or 3-hydroxydodecanoyl-3-hydroxydecanoate (C12-C10) as the lipid moiety under static growth conditions. The cloning and sequencing of three genes and proteins involved in the biosynthesis of monorhamnose-lipid (R1L) is described. Expression of two of these genes, i.e., rhlA and rhlB, together in P. chlororaphis NRRL B-30761 increases R1L production by at least 10-fold. Also the generation of a recombinant P. chlororaphis NRRL B-30761 capable of synthesizing dirhamnose-lipid (R2L) is described. Characterization of R1L and R2L produced by the recombinant P. chlororaphis NRRL B-30761 is also described.

Abstract: A process for producing rhamnolipids involving culturing Pseudomonas chlororaphis strain NRRL B-30761 in a first aqueous culture medium containing about 0.3% NH4H2PO4, about 0.2% K2HPO4, about 0.2% carbon source, about 0.5 mg/L FeSO4, and about 0.1% MgSO4 for about 24–about 48 hours at about 25°–about 30° C. with orbital shaking, and then culturing Pseudomonas chlororaphis strain NRRL B-30761 in a static second aqueous culture medium containing per liter about 2% carbon source, about 0.7 g KH2PO4, about 0.9 g Na2HPO4, about 2 g NaNO3, about 0.4 g MgSO4.7H2O, and about 0.1 g CaCl2.2H2O for at least about 72 hours at about 20°–about 23° C., wherein the first and second aqueous culture medium contains only one source of carbon.