Violacein: Properties and Production of a Versatile Bacterial Pigment

Abstract

Violacein-producing bacteria, with their striking purple hues, have undoubtedly piqued the curiosity of scientists since their first discovery. The bisindole violacein is formed by the condensation of two tryptophan molecules through the action of five proteins. The genes required for its production, vioABCDE, and the regulatory mechanisms employed have been studied within a small number of violacein-producing strains. As a compound, violacein is known to have diverse biological activities, including being an anticancer agent and being an antibiotic against Staphylococcus aureus and other Gram-positive pathogens. Identifying the biological roles of this pigmented molecule is of particular interest, and understanding violacein's function and mechanism of action has relevance to those unmasking any of its commercial or therapeutic benefits. Unfortunately, the production of violacein and its related derivatives is not easy and so various groups are also seeking to improve the fermentative yields of violacein through genetic engineering and synthetic biology. This review discusses the recent trends in the research and production of violacein by both natural and genetically modified bacterial strains.

Bacteria utilizing plant‐derived carbon in the rhizosphere of Triticum aestivum change in different depths of an arable soil

“…Actinobacteria and Streptomyces as well as Duganella and Janthinobacterium , all observed in our study in different soil depths with differing 13 C labelling intensity, are known for their ability to produce secondary metabolites with antimicrobial activities (Basilio et al ., ; Choi et al ., ; Viaene et al ., ). Many of these taxa are discussed in the context of biocontrol (Haesler et al ., ).…”

Grazing of leaf‐associated Cercomonads (Protists: Rhizaria: Cercozoa) structures bacterial community composition and function

“…In addition both Cercomonas species favoured Diplosphaera (Opitutae), but strongly suppressed Rhizobium (Alphaproteobacteria), and also Comamonas and Duganella thus leading to a general and strong reduction of Betaproteobacteria. Especially the strong decrease in Duganella and Janthinobacterium in presence of C. hederae was surprising, since both genera contain taxa producing violacein (Choi et al ., ), which is highly toxic to several protists (Matz and Kjelleberg, ). The other protist taxa did not proliferate as well as C. hederae on the bacterial communities.…”

Sequential Mycoplasma pneumoniae pneumonia and Chromobacterium violaceum skin abscess in a pediatric patient

“…The organism produces a natural antibiotic called violacein encoded by a cluster of 4 genes, vioABCD, within a single operon. Its anticancerous and anti-bacterial activities would have potential implications in future clinical therapeutic or biotechnological applications with industrial benefits [13,22,23].…”