Relationship between mycobacterial species and their carotenoid pigments

A study of the relationship between mycobacterial species and their carotenoid pigments was carried out. According to the carotenoid pigments contained, the mycobacterial species tested were divided into four groups: the first group of Mycobacterium kansasii and M. marinum, which formed principally only beta-carotene; the second group of M. gordonae, M. scrofulaceum, M. szulgai, M. xenopi, M. flavescens, M. phlei, M. rhodesiae, M. neoaurum, and M. aichiense, which formed beta-carotene and a zeaxanthin-like substance; the third group of M. aurum and M. obuense, which formed beta-carotene and an eschscholtzxanthin-like substance; and the fourth group of M. chubuense and M. tokaiense, which formed beta-carotene and zeaxanthin- and eschscholtzxanthin-like substances. The common carotenoid pigment throughout the genus Mycobacterium was beta-carotene and the hypophasic carotenoids differed according to the species.     

Fatty acid and carotenoid composition ofRhodotorula strains

Lipid content and composition of fatty acids with 6–25 carbon atoms were studied on strains of the 13 pink or red yeast species belonging to the genus Rhodotorula. The total amount of lipid represented an average of 13% of the dry weight. The neutral and polar lipid fractions were analyzed separately. For all the strains studied, the major fatty acids in both fractions were oleic, linoleic and palmitic acids, which formed 80% of the total number of fatty acids. A notable amount of arachidonic acid, a precursor of eicosanoid hormones, was found in R. acheniorum, R. aurantiaca and R. bacarum. Depending on the strain, 1–10 carotenoid pigments were detected; β-carotene was always the major carotenoid present. Received: 13 December 1994 / Accepted: 18 May 1995     

Numerical classification of Rhodococcus equi and related actinomycetes

Eighty-three strains received as Corynebacterium or Rhodococcus equi and marker cultures of Corynebacterium and Rhodococcus species were subjected to numerical phenetic analyses using 112 unit characters. The data were examined using the simple matching ( S _SM) and Jaccard ( S _J) coefficients and clustering was achieved using the average linkage algorithm. Cluster composition was not markedly affected by the coefficient used or by test error, estimated at 2.9%. Most of the strains received as R. (C.) equi formed a distinct and homogeneous cluster in the aggregate Rhodococcus taxon, the strains of which were sharply separated from marker cultures of C. pseudotuberculosis and C. renale. The taxon R. equi was redescribed and Nocardia calcarea Metcalf & Brown reduced to a subjective synonym of R. erythropolis (Gray & Thornton) Goodfellow & Alderson.     

Distribution and application of mycobactins for the characterization of species within the genus Rhodococcus

Representatives of 11 species of Rhodococcus were examined for their ability to synthesize mycobactin, a lipid-soluble siderophore, following iron-limited growth on solidified glycerol/asparagine medium. Rhodococcus bronchialis, R. terrae and R. rubropertinctus formed mycobactins, whereas the remaining species (R. coprophilus, R. equi, R. erythropolis, R. rhodnii, R. rhodochrous, R. ruber, R. maris and R. luteus) failed to synthesize these compounds even under conditions of strictly iron-limited growth. The mycobactins from R. terrae and R. rubropertinctus showed close similarity by thin-layer chromatography and high-performance liquid chromatography and could be easily distinguished from that of R. bronchialis.     

Energetic constraints on expression of carotenoid-based plumage coloration

Carotenoid pigments are used by many bird species as feather colorants, creating brilliant yellow, orange, and red plumage displays. Such carotenoid-based plumage coloration has been shown to function as an honest signal that is used in female mate choice. Despite recent interest in carotenoid-based ornamental traits, the basis for individual variation in expression of carotenoid-based plumage coloration remains incompletely understood. I tested the hypothesis that, independent of carotenoid access, food stress during molt would cause reduced expression of carotenoid pigmentation. I fed molting male House Finches Carpodacus mexicanus seed diets supplemented with either the red carotenoid pigment canthaxanthin or the yellow/orange carotenoid pigment β-cryptoxanthin (in the form of tangerine juice). Within each diet treatment, one group of males was given restricted food access and the other group was given unrestricted food access. Carotenoid supplements were placed in water so carotenoid access was controlled independent of food access. The results indicated a strong effect of both carotenoid access and food access on color display. Some males in the β-cryptoxanthin-supplemented group grew red plumage, suggesting that they can metabolically modify yellow pigments into red pigments, but no bird supplemented with β-cryptoxanthin grew plumage as red as birds supplemented with canthaxanthin. Males in the unrestricted food groups grew redder and more intensely pigmented plumage than males in the restricted food groups. These observations provide the best evidence to date of an energetic cost of carotenoid utilization in the generation of colorful plumage.     

Patterns of serum carotenoid accumulation and skin colour variation in kestrel nestlings in relation to breeding conditions and different terms of carotenoid supplementation

Carotenoids are pigments synthesised by autotrophic organisms. For nestlings of raptorial species, which obtain carotenoids from the consumption of other heterotrophic species, the access to these pigments can be crucial. Carotenoids, indeed, have fundamental health maintenance functions, especially important in developing individuals as nestling kestrels. The aim of this study was to investigate how body carotenoid levels and skin pigmentation vary in kestrel nestlings (Falco tinnunculus) in relation to nesting parameters. Furthermore, we experimentally altered carotenoid availability (short- medium- and long-term) for nestlings and investigated skin and serum variance. The skin colour variance of 151 nestlings was explained by nest of origin, age and by the body condition (body mass corrected by age), older nestlings with higher body condition being redder. No difference in skin colour was detected between sexes. Differences in hue (skin “redness”) between treatments did not emerge during the first week, but did occur 15 days after administration between long-term supplemented and control chicks. In contrast, the serum carotenoid concentration showed a treatment-dependent increase after 5 days from the first carotenoid administration and at least after two supplemented feedings. In general, hue but not serum carotenoids, was correlated with the body condition of nestlings. Based on the increased skin pigmentation of nestling kestrels in the long-term experimental group, we suggest carotenoid availability to be limited for colour expression. The small increase of serum carotenoids due to supplementation is consistent with the hypothesis that there is a physiological constraint on these pigments, as well as an environmental limitation. The presented results are useful for the understanding of carotenoid uptake and accumulation by a wild raptorial species, located at the top of the food web, highlighting that carotenoids are a limited resource for kestrel nestlings.     

Rhodococcus aetherivorans sp. nov., a new species that contains methyl t-butyl ether-degrading actinomycetes

The taxonomic positions of two actinomycetes, strains Bc663 and 10bc312T, provisionally assigned to the genus Rhodococcus were determined using a combination of genotypic and phenotypic properties. The organisms have phenotypic properties typical of members of the genus Rhodococcus and were assigned to the 16S rRNA subgroup which contains Rhodococcus rhodochrous and closely related species. The two strains, which have many phenotypic features in common, belong to the same genomic species albeit one readily separated from Rhodococcus ruber with which they form a distinct phyletic line. The organisms were also distinguished from all of the species classified in the R. rhodochrous subgroup, including R. ruber, using a combination of phenotypic properties. The genotypic and phenotypic data show that strains Bc663 and 10bc312T merit recognition as a new species of Rhodococcus. The name proposed for the new species is Rhodococcus aetherivorans (10bc312T = DSM 44752T = NCIMB 13964T).     

Carotenoids, immunocompetence, and the information content of sexual colors: an experimental test

Many male birds use carotenoid pigments to acquire brilliant colors that advertise their health and condition to prospective mates. The direct means by which the most colorful males achieve superior health has been debated, however. One hypothesis, based on studies of carotenoids as antioxidants in humans and other animals, is that carotenoids directly boost the immune system of colorful birds. We studied the relationship between carotenoid pigments, immune function, and sexual coloration in zebra finches (Taeniopygia guttata), a species in which males incorporate carotenoid pigments into their beak to attract mates. We tested the hypotheses that increased dietary carotenoid intake enhances immunocompetence in male zebra finches and that levels of carotenoids circulating in blood, which also determine beak coloration, directly predict the immune response of individuals. We experimentally supplemented captive finches with two common dietary carotenoid pigments (lutein and zeaxanthin) and measured cell-mediated and humoral immunity a month later. Supplemented males showed elevated blood-carotenoid levels, brighter beak coloration, and increased cell-mediated and humoral immune responses than did controls. Cell-mediated responses were predicted directly by changes in beak color and plasma carotenoid concentration of individual birds. These experimental findings suggest that carotenoid-based color signals in birds may directly signal male health via the immunostimulatory action of ingested and circulated carotenoid pigments.     

Concerted Shifts in Absorption Maxima of Yellow and Red Plumage Carotenoids Support Specialized Tuning of Chromatic Signals to Different Visual Systems in Near-Passerine Birds

Recent evidence that absorption maxima (λR_min) expressed by colorful plumage pigments align to diagnostic cone sensitivities of affiliated visual systems suggests that birds employ specialized signals in relation to their color vision. However, these studies compared different pigments and clades for the violet (porphyrins in non-passerines) and ultraviolet (carotenoids in passerines) sensitive system, which confounds chemistry and phylogeny with tuning patterns. To test whether signal alignments to violet (VS) and ultraviolet (UVS) systems transcend confounding factors, parallel analyses were conducted for a diversity of near-passerines, a group in which plumage carotenoids occur in taxa with either visual system. Conventional and phylogenetically informed analyses confirmed earlier findings: short wavelength absorbing (yellow carotenoid) pigments aligned λR_min with the violet-sensitive (V) cone of VS species but with the short wavelength-sensitive (S) cone of UVS species, whereas long wavelength-absorbing (red carotenoid) pigments aligned only with the S cone of VS species. More extensive variation among VS yellow carotenoids produced λR_min alignments to cone sensitivities that differed at shorter (peaks) versus longer (overlaps) wavelengths. Ancestral trait reconstructions indicated that signals evolved to match pre-existing VS systems, but did not resolve scenarios for UVS systems. Regardless of historical details, alignments expressed a higher-level pattern in which λR_min values were blue-shifted for yellow and red carotenoids in VS compared to UVS species, a pattern opposite that expressed by receptor sensitivities between systems. Thus, generalized functional designs attributed to avian color vision allow for specialized visual communication through the development of chromatic signals suited to each perceptual system.     

Pigmented basidiomycete yeasts are a promising source of carotenoids and ubiquinone Q10

Strains of basidiomycete yeasts isolated from different sources were studied in order to determine the content of carotenoid pigments and ubiquinone Q10 for subsequent selection work to obtain producers of these substances. High specific productivity of carotenoids (600-700 mg/g) was revealed in the representatives of the following species: Cystofilobasidium capitatum. Rhodosporidium diobovatum, R. sphaerocarpum. Rhodotorula glutinis, Rh. minuta, and Sporobolomyces roseus. The ratio of the major pigments (torulene, torularhodine, and beta-carotene) in the representatives of different species was studied. Certain specific features of pigment formation in relation to the taxonomic position of the yeasts were determined. Eurybiont species with substantial ecological lability are the most active producers of carotenoids and ubiquinone Q10 among the epiphytes. It is the first time a comparative analysis of the coenzyme Q10 content in different taxa has been performed using several strains of the same species. The maximal coenzyme Q10 production (1.84 mg/g of dry biomass) was found in the yeast species R. sphaerocarpum.     

CAROTENOID COMPOSITION OF MARINE RED ALGAE1

Photosynthetic organisms possess carotenoids that function either as accessory, photoprotective, or structural pigments. Therefore, the carotenoid profile provides information about certain photoacclimation and photoprotection responses. Carotenoids are also important chemosystematic markers because specific enzymes mediate each step of carotenoid biosynthesis. For red algae, diverse and often contradictory carotenoid compositions have been reported. As a consequence, it is difficult to infer the physiological importance of carotenoids in Rhodophyta. To characterize the relationship between carotenoid composition, rhodophycean phylogeny, and the presence of potentially photoprotective pigments, we analyzed the carotenoid composition of 65 subtropical species from 12 orders and 18 rhodophyte families. Our results showed that red algae do not present a unique carotenoid profile. However, a common profile was observed up to the level of order, with exception of the Ceramiales and the Corallinales. The main difference between profiles is related to the xanthophyll that represents the major carotenoid. In some species lutein is the major carotenoid while in others it is substituted by zeaxanthin or antheraxanthin. The presence of this epoxy carotenoid together with the presence of violaxanthin that are xanthophyll cycle (XC)‐related pigments was found in four of the 12 analyzed orders. The carotenoid pigment profiles are discussed in relation to Rhodophyta phylogeny, and it is suggested that the xanthophyll cycle‐related pigments appeared early in the evolution of eukaryotic phototrophs.     

Light‐induced pigment degradation in leaves and ripening fruits studied in situ with reflectance spectroscopy

Pigment breakdown mediated by activated oxygen species is a consequence and a general symptom of oxidative stress and injury to plants. We have attempted to estimate the patterns of pigment bleaching and follow pigment susceptibility to irradiation as related to the process of senescence/ripening. Light‐induced pigment breakdown was studied in situ in the leaves of a shade‐requiring plant, wax flower ( Hoya carnosa R. Br.), as well as in apple ( Malus domestica Borlh. cv. Zhigulevskoe) and lemon ( Citrus limon Burm. cv. Pavlovsky) fruits, using reflectance spectroscopy. It was found that the sensitivity of plant pigments to photobleaching increases as ripening progresses in lemon fruit. Kinetic analysis showed that in all systems a rapid breakdown of the pigment occurs after a lag‐phase. The signature analysis revealed a common pattern of chlorophyll and carotenoid changes, but degradation of the individual pigments was found to be inhomogeneous. Both in lemon and apple fruits a decrease in reflectance in the band of carotenoid absorption preceded pigment photodestruction. In the fruits, the bulk of chlorophyll b and the long‐wavelength chlorophyll a forms were degraded at early stages of the process whereas the breakdown of both chlorophylls in H. carnosa leaves was more synchronous. Prolonged irradiation induced bleaching of the main chlorophyll a band with maximum at 678 nm in the difference spectra, as well as carotenoids. Some features of reflectance spectra in the bands of chlorophyll and carotenoid absorption were found to be suitable for the differentiation of photo‐induced pigment breakdown from the transformation of the pigments taking place during senescence.     

Pigmented basidiomycetous yeasts are a promising source of carotenoids and ubiquinone Q<Subscript>10</Subscript>

Strains of basidiomycetous yeasts isolated from different sources were studied in order to determine the content of carotenoid pigments and ubiquinone Q₁₀ for subsequent selection work to obtain producers of these substances. The high specific productivity of carotenoids (600–700 mg/g) was revealed in the representatives of the following species: Cystofilobasidium capitatum, Rhodosporidium diobovatum, R. sphaerocarpum, Rhodotorula glutinis, Rh. minuta, and Sporobolomyces roseus. The ratio of the major pigments (torulene, torularhodine, and β-carotene) in the representatives of different species was studied. Certain specific features of pigment formation in relation to the taxonomic position of the yeasts were determined. Eurybiont species with substantial ecological lability are the most active producers of carotenoids and ubiquinone Q₁₀ among the epiphytes. It is the first time a comparative analysis of the coenzyme Q₁₀ content in different taxa has been performed using several strains of the same species. The maximal coenzyme Q₁₀ production (1.84 mg/g of dry biomass) was found in the yeast species R. sphaerocarpum.     

Lutein-based plumage coloration in songbirds is a consequence of selective pigment incorporation into feathers

Many birds obtain colorful carotenoid pigments from the diet and deposit them into growing tissues to develop extravagant red, orange or yellow sexual ornaments. In these instances, it is often unclear whether all dietary pigments are used as integumentary colorants or whether certain carotenoids are preferentially excluded or incorporated into tissues. We examined the carotenoid profiles of three New World passerines that display yellow plumage coloration—the yellow warbler (Dendroica petechia), common yellowthroat (Geothlypis trichas) and evening grosbeak (Coccothraustes vespertinus). Using high-performance liquid chromatography, we found that all species used only one carotenoid—lutein—to color their plumage yellow. Analyses of blood carotenoids (which document those pigments taken up from the diet) in two of the species, however, revealed the presence of two dietary xanthophylls—lutein and zeaxanthin—that commonly co-occur in plants and animals. These findings demonstrate post-absorptive selectivity of carotenoid deposition in bird feathers. To learn more about the site of pigment discrimination, we also analyzed the carotenoid composition of lipid fractions from the follicles of immature yellow-pigmented feathers in G. trichas and D. petechia and again detected both lutein and zeaxanthin. This suggests that selective lutein incorporation in feathers is under local control at the maturing feather follicle.     

EFFECTS OF IRON AND LIGHT STRESS ON THE BIOCHEMICAL COMPOSITION OF ANTARCTIC PHAEOCYSTIS SP. (PRYMNESIOPHYCEAE). II. PIGMENT COMPOSITION

A strain of Phaeocystis sp., isolated in the Southern Ocean, was cultured under iron- and light-limited conditions. The cellular content of chlorophyll a and accessory light-harvesting (LH) pigments increased under low light intensities. Iron limitation resulted in a decrease of all light-harvesting pigments. However, this decrease was greatly compensated for by a decrease in cell volume. Cellular concentrations of the LH pigments were similar for both iron-replete and iron-deplete cells. Concentrations of chlorophyll a were affected only under low light conditions, wherein concentrations were suppressed by iron limitation. Ratios of the LH pigments to chlorophyll a were highest for iron-deplete cells under both light conditions. The photoprotective cycle of diato/diadinoxanthin was activated under high light conditions, and enhanced by iron stress. The ratio of diatoxanthin to diadinoxanthin was highest under high light, low iron conditions.   Iron limitation induced synthesis of 19'-hexanoyloxyfucoxanthin and 19'-butanoyloxyfucoxanthin at the cost of fucoxanthin. Fucoxanthin formed the main carotenoid in iron-replete Phaeocystis cells, whereas for iron-deplete cells 19'-hexanoyloxyfucoxanthin was found to be the main carotenoid. This shift in carotenoid composition is of importance in view of the marker function of both pigments, especially in areas where Phaeocystis sp. and diatoms occur simultaneously. A hypothesis is presented to explain the transformation of fucoxanthin into 19'-hexanoyloxyfucoxanthin and 19'-butanoyloxyfucoxanthin, referring to their roles as a light-harvesting pigment.     

Carotenoid pigments in rust fungi: Extraction,separation, quantification and characterisation

Diseases caused by rust fungi represent critical constraints to global plant production. A characteristic feature of rust pathogens is the striking pigments they produce in one or more spore forms, which give them a rusty appearance. Here, we review the literature published to date on the extraction, separation, quantification and characterisation of carotenoid pigments in rust fungi. These pigments are thought to protect rust fungi against UV radiation and oxidative stress, and possibly act as virulence factors. The yellow-orange colour of some rust species is due to carotenoid pigments. Four carotenoids have been found in rust fungi: phytoene, lycopene, γ-carotene and β-carotene, but their relative contributions to biological functions are largely unknown. Different pre-processes and storage of spore materials, as well as different extraction processes, have been applied in a wide range of investigations on rust spore pigments. We find that the value of the current literature on rust carotenoids for taxonomic diagnostics in understanding the evolution of pigment biosynthesis and in assessing their role in pathogenesis is limited. Re-investigation of rust carotenoid composition using modern analytical technologies is therefore critical to further these fields of research. Our review includes detailed guidance on choice of techniques for rust carotenoid experimental analyses.     

Molecular diversity, metabolic transformation, and evolution of carotenoid feather pigments in cotingas (Aves: Cotingidae)

Carotenoid pigments were extracted from 29 feather patches from 25 species of cotingas (Cotingidae) representing all lineages of the family with carotenoid plumage coloration. Using high-performance liquid chromatography (HPLC), mass spectrometry, chemical analysis, and ¹H-NMR, 16 different carotenoid molecules were documented in the plumages of the cotinga family. These included common dietary xanthophylls (lutein and zeaxanthin), canary xanthophylls A and B, four well known and broadly distributed avian ketocarotenoids (canthaxanthin, astaxanthin, ??-doradexanthin, and adonixanthin), rhodoxanthin, and seven 4-methoxy-ketocarotenoids. Methoxy-ketocarotenoids were found in 12 species within seven cotinga genera, including a new, previously undescribed molecule isolated from the Andean Cock-of-the-Rock Rupicola peruviana, 3??-hydroxy-3-methoxy-??,??-carotene-4-one, which we name rupicolin. The diversity of cotinga plumage carotenoid pigments is hypothesized to be derived via four metabolic pathways from lutein, zeaxanthin, ??-cryptoxanthin, and ??-carotene. All metabolic transformations within the four pathways can be described by six or seven different enzymatic reactions. Three of these reactions are shared among three precursor pathways and are responsible for eight different metabolically derived carotenoid molecules. The function of cotinga plumage carotenoid diversity was analyzed with reflectance spectrophotometry of plumage patches and a tetrahedral model of avian color visual perception. The evolutionary history of the origin of this diversity is analyzed phylogenetically. The color space analyses document that the evolutionarily derived metabolic modifications of dietary xanthophylls have resulted in the creation of distinctive orange-red and purple visual colors.     

Digital image processing-an alternate tool for monitoring of pigment levels in cultured cells with special reference to green alga Haematococcus pluvialis

A method for analyzing carotenoid content in Haematococcus pluvialis, a green alga was developed using digital image processing (DIP) and an artificial neural network (ANN) model. About 90 images of algal cells in various phases of growth were processed with the tools of DIP. A good correlation of R(2)=0.967 was observed between carotenoid content as estimated by analytical method and DIP. Similar correlation was also observed in case of chlorophyll. Since the conventional methods of carotenoid estimation are time consuming and result in loss of pigments during analysis, DIP method was found to be an effective online monitoring method. This method will be useful in measurement of pigments in cultured cells.     

Carotenoid limitation and allocation priorities in asynchronous raptor nestlings

The evolution and maintenance of conspicuous animal traits and communication signals have long fascinated biologists. Many yellow–red conspicuous traits are coloured by carotenoid pigments, and in some species they are displayed at a very young age. In nestling birds, the functions and proximate mechanisms of carotenoid‐pigmented traits are probably different and not as well known as those of adults. Here we investigated how Montagu's harrier (Circus pygargus) nestlings within structured families used a limited resource, carotenoid pigments, and whether they used these for increasing coloration (deposition in integuments) or for mounting a response to a phytohaemagglutinin (PHA) challenge, which measures pro‐inflammatory potential and aspects of cellular immune responsiveness. We manipulated carotenoid availability, using dietary carotenoid supplementations, and show that when supplemented, nestlings primarily allocated supplemental carotenoids to increase their coloration, irrespective of their sex, but depending of their position within the brood. Responses to PHA challenge were condition‐dependent, but depending on carotenoid availability. Moreover, how nestlings allocated carotenoids depended on their rank within the brood, which in turn influenced their level of carotenoid limitation (first‐hatched nestlings being less constrained than later‐hatched nestlings). We discuss why nestlings would use supplemental carotenoids for increasing bare parts coloration rather than for responding to a PHA challenge, and the potential benefits for doing so in a parent–offspring communication context. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 13–24.