Bio-indigo production in two different fermentation systems using recombinant Escherichia coli cells harboring a flavin-containing monooxygenase gene (fmo)

Enhanced indirubin production in recombinant Escherichia coli harboring a flavin-containing monooxygenase gene by cysteine supplementation

“…In our previous batch fermentation study, it was found that recombinant E. coli pBlue 1.7 cells harboring the fmo gene produced indigo and indirubin by utilizing tryptophan as a substrate under high oxygen level (3 vvm of air supply) (Han et al, 2011). Under this condition, the major product (>99%) was indigo and a small amount of indirubin was produced (Table 1).…”

“…Rui et al reported that they convert 0.5 mM indole to 0.2 mM indirubin and 0.1 mM indigo in Tris-HCl buffer using Escherichia coli TG1cells harboring a toluene ortho-monooxygenase gene of Burkholderia cepacia G4. Our previous studies showed that recombinant E. coli DH5␣ cells harboring a flavin-containing monooxygenase (FMO) gene from Methylophaga aminisulfidivorans MP T (Choi et al, 2003) produced indirubin (≤5 mg/L) and indigo (920 mg/L) in a 5 L fermenter containing tryptophan (2 g/L) medium (Han et al, 2008(Han et al, , 2011.…”

Employing a biochemical protecting group for a sustainable indigo dyeing strategy

“…To combat environmental concerns, microbial production of indigo has previously been targeted as a replacement for chemical synthesis 8–11 . These efforts offered considerable environmental improvements by removing the need for the harmful chemicals used in indigo synthesis; however, a reducing agent was still required to reduce the insoluble indigo to the soluble leucoindigo for dyeing.…”

“…1a). We leveraged the work of previous groups to biosynthesize the indigo precursor indoxyl from tryptophan in Escherichia coli 8–11 . However, we also expressed a glucosyltransferase to stabilize indoxyl, preventing spontaneous dimerization by protecting the reactive hydroxyl with a glucosyl group.…”

Indigo biosynthesis by Comamonas sp. MQ

“…It was traditionally produced by extraction of plants such as Polygonum tinctorium (Bechtold et al 2002), but is now primarily produced by chemical synthesis. Because of the toxic wastewater generated by chemical processes, researchers have been trying to develop greener methods for indigo production, among which the microbial production of indigo could be a competitive alternative (Murdock et al 1993;Qu et al 2010;Han et al 2011).…”