Production Of Orange Pigments Research Articles

Optix regulates nanomorphology of butterfly scales primarily via its effects on pigmentation

Previous studies have shown that Optix regulates lower lamina thickness and the type of pigment that is produced in wing scales of a few butterfly species. However, the role of Optix in regulating pigment production across species, and in regulating additional aspects of scale morphology remains to be investigated. By combining microspectrophotometry, scanning electron microscopy, and focused ion beam technology on wild-type and Optix Bicyclus anynana crispants, we show that Optix regulates the production of orange pigments (ommochromes), represses the production of brown pigments (melanins), and regulates the morphology of the lower and upper surface of orange scales. Our findings suggest a conserved role of Optix as a switch gene that activates ommochrome and represses melanin synthesis across butterflies. By comparing these effects with other mutations, where only melanin is removed from scales, we propose that pigmentary changes, alone, affect the way that chitin polymerizes within a scale, changing lower lamina thickness as well as multiple intricate structures of the upper surface.

Low-Frequency Magnetic Field of Appropriate Strengths Changed Secondary Metabolite Production and Na+ Concentration of Intracellular and Extracellular Monascus purpureus.

Monascus purpureus is used to yield edible pigments accompanied by mycotoxin-citrinin. A low-frequency (<300 Hz) magnetic field (LF-MF) affects microbial metabolism. The link of LF-MF with secondary metabolites and intracellular and extracellular Na+ levels in M. purpureus was determined. The fermentation broth was exposed to LF-MF during the first 2 days of fermentation and continuously cultured at 30°C and 200 rpm until the 8th day of fermentation. Results showed that LF-MF treatments didn't affect the growth of M. purpureus in liquid-state fermentation. Compared with the control, citrinin production showed a decrease of 45.0%, while yellow, red, and orange pigment production showed an increase of 72.9, 73.9, and 40.1%, respectively, with LF-MF treatment of 1.6 mT. This was in agreement with downregulation of pksCT and ctnA, and upregulation of pksPT, pigR, veA, and laeA at the transcriptional level. Moreover, 1.6 mT LF-MF exposure caused the transfer of Na+ from extracellular to intracellular, which was validated through the upregulation of transmembrane sensor synthesis genes and the changes in the relative expression levels of the P-type ATPase and protein phosphatase genes. This study established that LF-MF could inhibit citrinin and stimulate pigment production and changeintracellular and extracellular Na+ concentrations. Bioelectromagnetics. 2020;41:289-297 © 2020 Bioelectromagnetics Society.

Maltose syrup residue as the substrate for Monascus pigments production

Abstract The objective of this study was to determine the effect of pH on the growth rate and production of pigments by Monascus ruber from maltose syrup residue as a substrate. The cultivations were carried out in solid and submerged media under different pH conditions. The highest radial growth rate occurred when the Monascus ruber was cultivated at pH 6.5 and the production of yellow pigments occurred at low pH values (2.0 and 2.5), whereas the production of orange pigments occurred at pH 3.0 and 3.5 and that of red pigments when the fungus was cultivated above pH 4.0. The results showed that the pH value had a significant influence on the radial growth rate and production of pigments, and especially on the profile of yellow, orange and red pigments when cultivated in a medium containing maltose syrup. Maltose syrup was shown to be a potential substrate for the production of pigments by Monascus ruber, potentiating the use of byproducts from the syrup processing industry to produce microbial pigments.

Comparative Methylome Analysis Reveals Perturbation of Host Epigenome in Chestnut Blight Fungus by a Hypovirus.

In eukaryotic genomes, DNA methylation is an important type of epigenetic modification that plays crucial roles in many biological processes. To investigate the impact of a hypovirus infection on the methylome of Cryphonectria parasitica, the chestnut blight fungus, whole-genome bisulfite sequencing (WGBS) was employed to generate single-base resolution methylomes of the fungus with/without hypovirus infection. The results showed that hypovirus infection alters methylation in all three contexts (CG, CHG, and CHH), especially in gene promoters. A total of 600 differentially methylated regions (DMRs) were identified, of which 144 could be annotated to functional genes. RNA-seq analysis revealed that DNA methylation in promoter is negatively correlated with gene expression. Among DMRs, four genes were shown to be involved in conidiation, orange pigment production, and virulence. Taken together, our DNA methylomes analysis provide valuable insights into the understanding of the relationship between DNA methylation and hypovirus infection, as well as phenotypic traits in C. parasitica.

Kinetic of orange pigment production from Monascus ruber on submerged fermentation.

Pigments produced by species of Monascus have been used to coloring rice, meat, sauces, wines and beers in East Asian countries. Monascus can produce orange (precursor), yellow and red pigments. Orange pigments have low solubility in culture media and when react with amino groups they become red and largely soluble. The orange pigments are an alternative to industrial pigment production because the low solubility facilitates the downstream operations. The aim of this work was to study the kinetic on the production of orange pigments by Monascus ruber CCT 3802. The shaking frequency of 300rpm was favorable to production, whereas higher shaking frequencies showed negative effect. Pigment production was partially associated with cell growth, the critical dissolved oxygen concentration was between 0.894 and 1.388mgO2L-1 at 30°C, and limiting conditions of dissolved oxygen decreased the production of orange pigments. The maintenance coefficient (mo) and the conversion factor of oxygen in biomass (Yo) were 18.603mgO2g x-1 h-1 and 3.133gxgO 2-1 and the consideration of these parameters in the oxygen balance to estimate the biomass concentration provided good fits to the experimental data.

Description of Thermogemmatispora carboxidivorans sp. nov., a carbon-monoxide-oxidizing member of the class Ktedonobacteria isolated from a geothermally heated biofilm, and analysis of carbon monoxide oxidation by members of the class Ktedonobacteria

A thermophilic, aerobic, Gram-stain-positive bacterium (strain PM5(T)), which formed mycelia of irregularly branched filaments and produced multiple exospores per cell, was isolated from a geothermally heated biofilm. Strain PM5(T) grew at 40-65 °C and pH 4.1-8.0, with optimal growth at 55 °C and pH 6.0. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain PM5(T) belonged to the class Ktedonobacteria, and was related most closely to Thermogemmatispora onikobensis ONI-1(T) (97.7 % similarity) and Thermogemmatispora foliorum ONI-5(T) (96.1 %). Morphological features and fatty acid profiles (major fatty acids: iso-C17 : 0, iso-C19 : 0 and 12,17-dimethyl C18 : 0) supported the affiliation of strain PM5(T) to the genus Thermogemmatispora. Strain PM5(T) oxidized carbon monoxide [CO; 10±1 nmol h(-1) (mg protein)(-1)], but did not grow with CO as a sole carbon and energy source. Results from analyses of related strains indicated that the capacity for CO uptake occurred commonly among the members of the class Ktedonobacteria; 13 of 14 strains tested consumed CO or harboured coxL genes that potentially enabled CO oxidation. The results of DNA-DNA hybridization and physiological and biochemical tests allowed the genotypic and phenotypic differentiation of strain PM5(T) from the two recognized species of the genus Thermogemmatispora. Strain PM5(T) differed from Thermogemmatispora onikobensis ONI-1(T) in its production of orange pigment, lower temperature optimum, hydrolysis of casein and starch, inability to grow with mannitol, xylose or rhamnose as sole carbon sources, and utilization of organic acids and amino acids. Strain PM5(T) is therefore considered to represent a novel species, for which the name Thermogemmatispora carboxidivorans sp. nov. is proposed. The type strain is PM5(T) ( = DSM 45816(T) = ATCC BAA-2534(T)).

Quorum sensing‐controlled Evr regulates a conserved cryptic pigment biosynthetic cluster and a novel phenomycin‐like locus in the plant pathogen, Pectobacterium carotovorum

Pectobacterium carotovorum SCRI193 is a phytopathogenic Gram-negative bacterium. In this study, we have identified a novel cryptic pigment biosynthetic locus in P. carotovorum SCRI193 which we have called the Pectobacterium orange pigment (pop) cluster. The pop cluster is flanked by two tRNA genes and contains genes that encode non-ribosomal peptide synthases and polyketide synthase and produces a negatively charged polar orange pigment. Orange pigment production is activated when an adjacent transcriptional activator sharing sequence similarity with the Erwinia virulence regulator (Evr) is overexpressed. Evr was shown to positively activate its own transcription and that of the pigment biosynthetic genes and an unlinked locus encoding a phenomycin homologue. In addition, the expression of Evr and orange pigment production was shown to be regulated by N-(3-oxohexanoyl)-HSL (OHHL) quorum sensing and have a virulence phenotype in potato. Finally, by comparative genomics and Southern blotting we demonstrate that this pigment biosynthetic cluster is present in multiple P. carotovorum spp., Pectobacterium brasiliensis 1692 and a truncated version of the cluster is present in Pectobacterium atrosepticum. The conserved nature of this cluster in P. carotovorum and P. brasiliensis suggests that the pop cluster has an important function in these broad-host-range soft rotting bacteria, which is no longer required in the narrow-host-range P. atrosepticum SCRI1043.

Toward functional genomics in bacteria: analysis of gene expression in Escherichia coli from a bacterial artificial chromosome library of Bacillus cereus.

As the study of microbes moves into the era of functional genomics, there is an increasing need for molecular tools for analysis of a wide diversity of microorganisms. Currently, biological study of many prokaryotes of agricultural, medical, and fundamental scientific interest is limited by the lack of adequate genetic tools. We report the application of the bacterial artificial chromosome (BAC) vector to prokaryotic biology as a powerful approach to address this need. We constructed a BAC library in Escherichia coli from genomic DNA of the Gram-positive bacterium Bacillus cereus. This library provides 5.75-fold coverage of the B. cereus genome, with an average insert size of 98 kb. To determine the extent of heterologous expression of B. cereus genes in the library, we screened it for expression of several B. cereus activities in the E. coli host. Clones expressing 6 of 10 activities tested were identified in the library, namely, ampicillin resistance, zwittermicin A resistance, esculin hydrolysis, hemolysis, orange pigment production, and lecithinase activity. We analyzed selected BAC clones genetically to identify rapidly specific B. cereus loci. These results suggest that BAC libraries will provide a powerful approach for studying gene expression from diverse prokaryotes.

Paracoccus carotinifaciens sp. nov., a new aerobic gram-negative astaxanthin-producing bacterium.

The strain E-396T, isolated from soil, was Gram-negative, aerobic, orange-pigmented, rod-shaped, motile by peritrichous flagella and astaxanthin-producing. This organism produced carotenoids, mainly astaxanthin, and did not produce bacteriochlorophyll. The ubiquinone system was Q-10. Analysis of the 16S rRNA sequence of strain E-396T showed it to be a member of the alpha-3 subclass of the Proteobacteria, forming a cluster with the species of the genus Paracoccus. On the basis of the production of orange pigments and motility by peritrichous flagella, together with DNA-DNA reassociation data, it is concluded that the new isolate should be classified into a new species of the genus Paracoccus, Paracoccus carotinifaciens sp. nov. The type strain is E-396T (= IFO 16121T).

A screening test (GBS-Test) for urogenital carriage of group B streptococci

A commercial kit for the detection of group B streptococci (GBS-Test) is described. The test is based on orange pigment production after 2 days' incubation at 37 degrees C. It showed a 100% specificity and a sensitivity superior to that of a conventional selective broth method.

Genetic analysis of methicillin-resistant strains of Staphylococcus aureus; evidence for their evolution from a single clone.

Summary Methicillin-resistant staphylococci are characterised by: (a) chromosomal resistance to streptomycin, (b) tetracycline resistance determined by a stable plasmid, (c) production of orange pigment, (d) a similar degree of survival on glass. We consider that all or almost all isolates of methicillin-resistant staphylococci have evolved from a single clone. If so, plasmids determining a variety of antibiotic resistances (penicillinase, penicillinase/fusidic acid, erythromycin, erythromycin/lincomycin, neomycin and chloramphenicol) have probably been acquired in recent years by their transfer from other strains. One isolate (no. 11164) has probably acquired novobiocin resistance by mutation and lost the genes determining pigment and survival. Strain no. 13136 contains a “penicillinase plasmid” with a molecular weight of about 20 million daltons and a plasmid specifying high-level resistance to tetracycline (MIC 200 μg per ml) of molecular weight about 2.9 million daltons. The latter plasmid was also present in other methicillin-resistant strains. After storage of strain no. 13136, some colonies were resistant to only low levels of tetracycline (MIC 2.5 μg per ml). In these derivatives, the “tetracycline plasmid” of molecular weight 2.9 million daltons was replaced by a plasmid of 2.2 million daltons. Although methicillin resistance can be lost irreversibly from strains nos. 13136, 2273 and 9463, no discrete CCC-DNA component corresponding to a plasmid determining this resistance was resolved in any of them.