Pseudomonas aeruginosa rhamnolipids: biosynthesis and potential applications

Abstract

Pseudomonas aeruginosa produces and secretes rhamnose-containing glycolipid biosurfactants called rhamnolipids. This review describes rhamnolipid biosynthesis and potential industrial and environmental applications of rhamnolipids. Rhamnolipid production is dependent on central metabolic pathways, such as fatty acid synthesis and dTDP-activated sugars, as well as on enzymes participating in the production of the exopolysaccharide alginate. Synthesis of these surfactants is regulated by a very complex genetic regulatory system that also controls different P. aeruginosa virulence-associated traits. Rhamnolipids have several potential industrial and environmental applications including the production of fine chemicals, the characterization of surfaces and surface coatings, as additives for environmental remediation, and as a biological control agent. Realization of this wide variety of applications requires economical commercial-scale production of rhamnolipids.

Optimization of Nutrient Requirements and Culture Conditions for the Production of Rhamnolipid from Pseudomonas aeruginosa (MTCC 7815) using Mesua ferrea Seed Oil

“…Additionally, there are reports of vegetable oils depicting as more effective substrate in rhamnolipid production from P. aeruginosa compared to glucose, glycerol and hydrocarbons [15,[35][36][37]. However, in contrast to these findings Pseudomonas EMI strain used by Benincasa et al [14] showed that carbon sources such as glucose and glycerol were superior over the vegetable oils like olive and soya bean oil when tested with rhamnolipid yield and productivity.…”

“…There are certain reports that mark the type and concentration of carbon substrates which affect the production of rhamnolipid yield [18,35]. Wei et al…”

“…Their unique structures provide unique properties that lacks in commercial surfactants [2]. Moreover, it has application in petroleum industry which includes enhanced oil recovery (EOR), bioremediation and waste treatment to remove hazardous materials, pharmaceutical-cosmetics formulas, agriculture, food processing industries, detergents, laundry supplies and paint industries [3][4][5][6]. Recently, biosurfactants have received much attention in nanobiotechnology too [7,8].…”

Role of quorum sensing by Pseudomonas aeruginosa in microbial keratitis and cystic fibrosis

“…In addition to directly causing tissue destruction, elastase also protects P. aeruginosa during infection by degrading immunoglobulins and complement proteins (Bainbridge & Fick, 1989;Cripps et al, 1995). Another class of QS-controlled product that affects the immune system is rhamnolipids, bioactive molecules with surfactant properties, synthesized by RhlAB, with the most abundant being L-rhamnosyl-3-hydroxydecanoyl-3-hydroxydecanoate (rhamnolipid 1) and 2-O-a-L-rhamnopyranosyl-a-L-rhamnopyranosyl-b-hydroxydecanoyl-b-hydroxydecanoic acid (rhamnolipid 2, also referred to as rhamnolipid B by Jensen et al, 2007;Lang & Wullbrandt, 1999;Maier & Soberon-Chavez, 2000). Although rhamnolipids were initially proposed to play a role in maintaining void spaces between microcolonies or for biofilm dispersal in vitro, we have subsequently shown that PMNs are unable to eradicate bacterial cells within P. aeruginosa biofilms in vitro .…”

Development of an In Situ Biosurfactant Production Technology for Enhanced Oil Recovery

“…Biosurfactant production has traditionally been viewed as a mechanism to enhance hydrocarbon biodegradation by increasing the apparent aqueous solubility of the hydrocarbon [52][53][54][55][56][57][58][59][60][61] or by enhancing the interaction of the microbial cell with the hydrocarbon [60,62,63]. By dispersing or increasing the apparent solubility of poorly soluble hydrocarbons, especially polynuclear aromatic compounds, these compounds become more bioavailable and, thus, more amenable to biodegradation [57,61,[64][65][66].…”