Statistical Screening of Medium Components for Recombinant Production of Pseudomonas aeruginosa ATCC 9027 Rhamnolipids by Nonpathogenic Cell Factory Pseudomonas putida KT2440

Abstract

Rhamnolipids (RLs) produced by the opportunistic human pathogen Pseudomonas aeruginosa are considered as potential candidates for the next generation of surfactants. Large-scale production of RLs depends on progress in strain engineering, medium design, operating strategies, and purification procedures. In this work, the rhlAB genes extracted from a mono_RLs_producing strain of P. aeruginosa (ATCC 9027) were introduced to an appropriate safety host Pseudomonas putida KT2440. The capability of the recombinant strain was evaluated in various media. As a prerequisite for optimal medium design, a set of 32 experiments was performed in two steps for screening a number of macro-nutritional compounds. In the experiments, a two-level fractional factorial design resolution IV was followed by a two-level full factorial one. By means of this approach, it was observed that glycerol, yeast extract, and peptone have significant positive influence on recombinant RLs production while the yeast extract/peptone two-factor and glycerol/yeast extract/peptone three-factor interactions have considerable negative effects. A wide range of variation from 0 to 570 mg/l was obtained for RLs production during the screening experiments indicating the importance of medium optimization. The results point out the opportunity for possible higher yields of RLs through further screening, mixture/combined mixture designs, and high-cell-density cultivations.

Effect of Mono and Di-rhamnolipids on Biofilms Pre-formed by Bacillus subtilis BBK006

“…The presence of the mono-rhamnolipid rhamnosyl-3-hydroxydecanoyl-3-hydroxydecanoate Rha–C 10 –C 10 was revealed as a predominant peak of m/z 503 (Fig. 3 b), in accordance with the previous reports where it has been widely studied and surveyed for the past decade [ 1 , 16 , 22 ].…”

“…Biosurfactants are amphiphilic compounds produced on living surfaces, mostly on microbial cells [ 16 ]. Biosurfactants have long been reported as molecules with several applications in the industry: detergents, textiles, and with potential applications in environmental and biomedical related areas [ 8 ], and more recently as promising candidates for the inhibition of microbial biofilms with anti-adhesive and disruptors properties [ 7 ].…”

Pseudomonas putida—a versatile host for the production of natural products

“…Different promoters were evaluated for expression of the ca. 2-kb operon, namely the synthetic hybrid promoter P tac , (Ochsner et al 1995 ; Wittgens et al 2011 ; Setoodeh et al 2014 ), a set of completely synthetic promoters in comparison to P tac (Blank et al 2013 ), or the native regulation system via coexpression of the cognate autoinducer-dependent transcription factor/autoinducer synthase pair RhlR/RhlI from P. aeruginosa (Cha et al 2008 ; Cao et al 2012 ). Metabolic network analysis identified the PHA formation (see above) via PHA synthases PhaC1/C2 as a competitor for the precursor hydroxy fatty acid-ACP.…”

Production of microbial biosurfactants: Status quo of rhamnolipid and surfactin towards large‐scale production

“…Thus, a putatively constitutive auto-induction uncoupled from the quorum sensing regulation system was established. [36]. Maximum concentrations of up to 0.57 g/L were reported after medium optimization.…”

“…They reported values of 1.5 g/L with P. putida KT42C1 and LB medium supplemented with glucose . Setoodeh et al introduced the genes rhlAB from P. aeruginosa ATCC 9027 into P. putida KT2440 . Maximum concentrations of up to 0.57 g/L were reported after medium optimization.…”