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Avian embryos develop in an egg composition which reflects both maternal condition and the recent environment of their mother. In birds, yolk corticosterone (CORT) influences development by impacting pre‐ and postnatal growth, as well as nestling stress responses and development. One possible mechanism through which maternal CORT may affect offspring development is via changes to offspring DNA methylation. We sought to investigate this, for the first time in birds, by quantifying the impact of manipulations to maternal CORT on offspring DNA methylation. We non‐invasively manipulated plasma CORT concentrations of egg‐laying female zebra finches (Taeniopygia castanotis) with an acute dose of CORT administered around the time of ovulation and collected their eggs. We then assessed DNA methylation in the resulting embryonic tissue and in their associated vitelline membrane blood vessels, during early development (5 days after lay), using two established methods – liquid chromatography–mass spectrometry (LC–MS) and methylation‐sensitive amplification fragment length polymorphism (MS‐AFLP). LC–MS analysis showed that global DNA methylation was lower in embryos from CORT‐treated mothers, compared to control embryos. In contrast, blood vessel DNA from eggs from CORT‐treated mothers showed global methylation increases, compared to control samples. There was a higher proportion of global DNA methylation in the embryonic DNA of second clutches, compared to first clutches. Locus‐specific analyses using MS‐AFLP did not reveal a treatment effect. Our results indicate that an acute elevation of maternal CORT around ovulation impacts DNA methylation patterns in their offspring. This could provide a mechanistic understanding of how a mother's experience can affect her offspring's phenotype. [ABSTRACT FROM AUTHOR]

Microalgae are important renewable feedstock to produce biodiesel and high‐value chemicals. Different wavelengths of light influence the growth and metabolic activities of algae. Recent research has identified the light‐sensing proteins called photoreceptors that respond to blue or red light. Structural elucidations of algal photoreceptors have gained momentum over recent years. These include channelrhodopsins, PHOT proteins, animal‐like cryptochromes, and blue‐light sensors utilizing flavin‐adenine dinucleotide proteins. Pulsing light has also been investigated as a means to optimize energy inputs into bioreactors. This study summarizes the current structural and functional basis of photoreceptor modulation to optimize the growth, production of carotenoids and other high‐value metabolites from microalgae. The review also encompasses novel photobioreactor designs that implement different light regimes including light wavelengths and time to optimize algal growth and desired metabolite profiles for high‐value products. [ABSTRACT FROM AUTHOR]

The flavour of aquatic animal products is distinct from terrestrial foods, facilitating a competitive marketing advantage. However, the flavour of aquatic animals can also be highly variable. Importantly, differences are reported in the flavour of animals from aquaculture and wild‐capture systems. These differences can erode consumer acceptance of aquaculture products and reduce financial returns to producers. Mild 'fish‐like', 'marine', 'crustacean‐like', 'seafood' and 'sweet' odours are desirable. However, overt 'fish‐like', 'fatty' and 'earthy' odours are quality deficits and cause products to become unpalatable. Odorous volatile compounds are responsible for eliciting these characteristic odours. In this literature review, the odorous volatile compounds of 96 aquatic animal samples are reported, revealing 291 different compounds. Generalist compounds that are integral to the odour of aquatic animals are presented in addition to 86 compounds that elicit key characteristic odours. The influence of these compounds on aquatic animal flavour is explored and the specific factors likely to affect their manipulation in aquaculture products are discussed. The culture environment and diet are critical factors affecting volatile profiles of aquatic animals and are the variables that can be controlled by aquaculture producers. The information presented in this review can underpin the development of innovative aquaculture strategies that prevent environmental exposure of aquatic animals to unpalatable volatile compounds and facilitate the development of aquaculture diets that optimise the volatile profile of edible tissues. [ABSTRACT FROM AUTHOR]

SUMMARY: Conventional breeding efforts for iron (Fe) and zinc (Zn) biofortification of bread wheat (Triticum aestivum L.) have been hindered by a lack of genetic variation for these traits and a negative correlation between grain Fe and Zn concentrations and yield. We have employed genetic engineering to constitutively express (CE) the rice (Oryza sativa) nicotianamine synthase 2 (OsNAS2) gene and upregulate biosynthesis of two metal chelators – nicotianamine (NA) and 2′‐deoxymugineic acid (DMA) – in bread wheat, resulting in increased Fe and Zn concentrations in wholemeal and white flour. Here we describe multi‐location confined field trial (CFT) evaluation of a low‐copy transgenic CE‐OsNAS2 wheat event (CE‐1) over 3 years and demonstrate higher concentrations of NA, DMA, Fe, and Zn in CE‐1 wholemeal flour, white flour, and white bread and higher Fe bioavailability in CE‐1 white flour relative to a null segregant (NS) control. Multi‐environment models of agronomic and grain nutrition traits revealed a negative correlation between grain yield and grain Fe, Zn, and total protein concentrations, yet no correlation between grain yield and grain NA and DMA concentrations. White flour Fe bioavailability was positively correlated with white flour NA concentration, suggesting that NA‐chelated Fe should be targeted in wheat Fe biofortification efforts. Significance Statement: Nicotianamine (NA) and 2′‐deoxymugineic acid (DMA) are important chelators of iron (Fe) and zinc (Zn) in graminaceous plants. Field evaluation of biofortified wheat (Triticum aestivum) containing higher concentrations of NA, DMA, Fe, and Zn in wholemeal flour, white flour, and white bread demonstrated that grain NA and DMA concentrations do not correlate with yield and highlighted NA‐chelated Fe as a promising target for wheat biofortification programs. [ABSTRACT FROM AUTHOR]

Mixotrophic cultivation can increase microalgae productivity, yet the associated lipid metabolism remains mostly unknown. Stable isotope labeling was used to track assimilation of glycerol into the triacylglyceride (TAG) and membrane lipids of Nannochloropsis salina. In N‐replete media, glycerol uptake and 13C incorporation into acyl chains were, respectively, 6‐fold and 12‐fold higher than in N‐deplete conditions. In N‐replete cultures, 42% of the carbon in the consumed glycerol was assimilated into lipid acyl chains, mostly in membrane lipids rather than TAG. In N‐deplete cultures, only 11% of the limited amount of consumed glycerol was fixed into lipid acyl chains. Labeled lipid‐associated glycerol backbones were predominantly 13C3 labeled, suggesting that intact glycerol molecules were directly esterified with fatty acids/polar head groups. However, the presence of singly and doubly labeled lipid‐bound glycerol species suggested that some glycerol also went through the central carbon metabolism before forming glycerol‐3‐phosphate destined for lipid esterification. 13C incorporation was higher in the saturated and monounsaturated than the polyunsaturated acyl chains of TAG, indicating the flux of carbon from glycerol went first to de novo fatty acid synthesis before acyl editing reactions. The results demonstrate that nitrogen availability influences both glycerol consumption and utilization for lipid synthesis in Nannochloropsis, providing novel insights for developing mixotrophic cultivation strategies. [ABSTRACT FROM AUTHOR]

Salinity‐induced metabolic, ionic, and transcript modifications in plants have routinely been studied using whole plant tissues, which do not provide information on spatial tissue responses. The aim of this study was to assess the changes in the lipid profiles in a spatial manner and to quantify the changes in the elemental composition in roots of seedlings of four barley cultivars before and after a short‐term salt stress. We used a combination of liquid chromatography–tandem mass spectrometry, inductively coupled plasma mass spectrometry, matrix‐assisted laser desorption/ionization mass spectrometry imaging, and reverse transcription – quantitative real time polymerase chain reaction platforms to examine the molecular signatures of lipids, ions, and transcripts in three anatomically different seminal root tissues before and after salt stress. We found significant changes to the levels of major lipid classes including a decrease in the levels of lysoglycerophospholipids, ceramides, and hexosylceramides and an increase in the levels of glycerophospholipids, hydroxylated ceramides, and hexosylceramides. Our results revealed that modifications to lipid and transcript profiles in plant roots in response to a short‐term salt stress may involve recycling of major lipid species, such as phosphatidylcholine, via resynthesis from glycerophosphocholine. Accumulation of glycerophosphocholine may be a component in the salt stress response of seminal roots of barley seedlings by acting as an osmolyte and a substrate for phosphatidylcholine resynthesis following a short‐term salt stress. [ABSTRACT FROM AUTHOR]

Summary: Bread wheat (Triticum aestivum L.) is cultivated on more land than any other crop and produces a fifth of the calories consumed by humans. Wheat endosperm is rich in starch yet contains low concentrations of dietary iron (Fe) and zinc (Zn). Biofortification is a micronutrient intervention aimed at increasing the density and bioavailability of essential vitamins and minerals in staple crops; Fe biofortification of wheat has proved challenging. In this study we employed constitutive expression (CE) of the rice (Oryza sativa L.) nicotianamine synthase 2 (OsNAS2) gene in bread wheat to up‐regulate biosynthesis of two low molecular weight metal chelators – nicotianamine (NA) and 2′‐deoxymugineic acid (DMA) – that play key roles in metal transport and nutrition. The CE‐OsNAS2 plants accumulated higher concentrations of grain Fe, Zn, NA and DMA and synchrotron X‐ray fluorescence microscopy (XFM) revealed enhanced localization of Fe and Zn in endosperm and crease tissues, respectively. Iron bioavailability was increased in white flour milled from field‐grown CE‐OsNAS2 grain and positively correlated with NA and DMA concentrations. [ABSTRACT FROM AUTHOR]

Plant diseases caused by Phytophthora species are serious threats to agriculture and the natural environment. Genome sequencing has revealed the lack of a gene for canonical phospholipase C (PLC), an enzyme that was hitherto thought to be ubiquitous in eukaryotes. PLC acts in the hydrolysis of phosphatidylinositol 4,5–bisphosphate (PtdIns‐4,5‐P2), a membrane‐bound phospholipid critical for signal initiation in many cellular processes. Previous studies have not provided evidence of endogenous PtdIns‐4,5‐P2 in Phytophthora and, in the absence of canonical PLC, argued for redundancy or loss in the PLC pathway in Phytophthora. Using liquid chromatography mass spectrometry, we have detected endogenous PtdIns‐4,5‐P2 in Phytophthora cinnamomi. This is the first identification of the phospholipid in the genus, and is significant because it indicates that the signal transduction pathway of the PLC product, inositol 1,4,5‐trisphosphate (IP3), may have been retained in Phytophthora incorporating an as‐yet unidentified homolog or analog of PLC. [ABSTRACT FROM AUTHOR]

Advances in high-throughput, comprehensive small molecule analytical techniques have seen the development of the field of metabolomics. The coupling of mass spectrometry with high-resolution chromatography provides extensive chemical profiles from complex biological extracts. These profiles include thousands of compounds linked to gene expression, and can be used as taxonomic characters. Studies have shown metabolite profiles to be taxon specific in a range of organisms, but few have investigated taxonomically problematic plant taxa. This study used a phenetic analysis of metabolite profiles to test taxonomic boundaries in the Oleariaphlogopappa (Asteraceae) complex as delimited by morphological data. Metabolite profiles were generated from both field- and shade house-grown material, using liquid chromatography-mass spectrometry (LC-MS). Aligned profiles of 51 samples from 12 taxa gave a final dataset of over 10,000 features. Multivariate analyses of field and shade house material gave congruent results, both confirming the distinctiveness of the morphologically defined species and subspecies in this complex. Metabolomics has great potential in alpha taxonomy, especially for testing the boundaries of closely related taxa where DNA sequence data has been uninformative. [ABSTRACT FROM AUTHOR]

The lipid characteristics of microalgae are known to differ between species and change with growth conditions. This work provides a methodology for lipid characterization that enables selection of the optimal strain, cultivation conditions, and processing pathway for commercial biodiesel production from microalgae. Two different microalgal species, Nannochloropsis sp. and Chlorella sp., were cultivated under both nitrogen replete and nitrogen depleted conditions. Lipids were extracted and fractionated into three major classes and quantified gravimetrically. The fatty acid profile of each fraction was analyzed using GC-MS. The resulting quantitative lipid data for each of the cultures is discussed in the context of biodiesel and omega-3 production. This approach illustrates how the growth conditions greatly affect the distribution of fatty acid present in the major lipid classes and therefore the suitability of the lipid extracts for biodiesel and other secondary products. Biotechnol. Bioeng. 2013; 110: 2096-2104. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

• Experimental evidence suggests that nicotianamine (NA) is involved in the complexation of metal ions in some metal-hyperaccumulating plants. • Closely-related nickel (Ni)- and zinc (Zn)-hyperaccumulating species were studied to determine whether a correlation exists between the Ni and Zn concentrations and NA in foliar tissues. • A liquid chromatography–mass spectrometry (LC-MS) procedure was developed to quantify the NA and amino acid contents using the derivatizing agent 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. A strong correlation emerged between Ni and NA, but not between Zn and NA. Concentrations of NA andl-histidine (His) also increased in response to higher Ni concentrations in the hydroponic solution supplied to a serpentine population of Thlaspi caerulescens. An inversely proportional correlation was found between the iron (Fe) and Ni concentrations in the leaves. Correlations were also found between Zn and asparagine. • The results obtained in this study suggest that NA is involved in hyperaccumulation of Ni but not Zn. The inverse proportionality between the Ni and Fe concentrations in the leaf may suggest that Ni and Fe compete for complexation to NA. [ABSTRACT FROM AUTHOR]