Osmoadaptation mechanisms in prokaryotes: distribution of compatible solutes

Microorganisms respond to osmotic stress mostly by accumulating compatible solutes, either by uptake from the medium or by de novo synthesis. These osmotically activ molecules preserve the positive turgor pressure required for cell division. The diversity of compatible solutes is large but falls into a few major chemical categories; they are usually small organic molecules such as amino acids or their derivatives, and carbohydrates and their derivatives. Some are widely distributed in nature while others seem to be exclusively present in specific groups of organisms. This review discusses the diversity and distribution of known classes of compatible solutes found in prokaryotes as well as the increasing knowledge of the genes and pathways involved in their synthesis. The alternative roles of some archetypal compatible solutes not subject to osmoregulatory constraints are also discussed

Diversity, distribution and biosynthesis of compatible solutes in prokaryotes

Els microorganismes responen a l'estrès osmòtic acumulant, principalment, soluts compatibles, agafant-los del medi o per síntesi de novo. Aquestes molècules, osmòticament actives, conserven la pressió de turgència positiva necessària per a la divisió cel·lular. La diversitat de soluts compatibles és gran, però es divideix en unes quantes categories químiques essencials; són molècules orgàniques normalment petites, com els aminoàcids, o els seus derivats, i els carbohidrats, o els seus derivats. Alguns són àmpliament distribuïts en la natura, mentre que d'altres sembla que siguin presents exclusivament en grups específics d'organismes. Aquesta revisió parla de la diversitat i la distribució de classes conegudes de soluts compatibles trobats en procariotes, així com del coneixement creixent dels gens i les rutes que s'impliquen en la seva síntesi. També es parla de les rutes alternatives d'alguns soluts compatibles no subjectes a restriccions osmoregulatòries.Microorganisms respond to osmotic stress mostly by accumulating compatible solutes, either by uptake from the medium or by de novo synthesis. These osmotically active molecules preserve the positive turgor pressure required for cell division. The diversity of compatible solutes is large but falls into a few major chemical categories; they are usually small organic molecules such as amino acids or their derivatives, and carbohydrates or their derivatives. Some are widely distributed in nature while others seem to be exclusively present in specific groups of organisms. This review discusses the diversity and distribution of known classes of compatible solutes found in prokaryotes as well as the increasing knowledge of the genes and pathways involved in their synthesis. The alternative roles of some archetypal compatible solutes not subject to osmoregulatory constraints are also discussed

Dichotomaria marginata (Rhodophyta) as a bioindicator for marine pollution: An overview about its metabolites and adsorbed pollutants

Macroalgae are considered bioindicators for marine pollution, because they have the ability to quickly react to changes in their environment. In consequence, macroalgae populations fluctuate, according to species characteristics and adaptive strategies. Their cell wall polysaccharides contain sulfate groups that are capable of retaining and accumulating heavy metals. In addition to traditional contaminants, emerging pollutants are being recognized in aquatic environments. Herein, emerging pollutants have been identified after being desorbed from the macroalga Dichotomaria marginata, collected from Fortaleza Beach, Ubatuba -SP, Brazil. Based on that algal polysaccharide networks have the potential of forming hydrogen bonds with polar compounds, it was hypothesized that these pollutants would be bound to sugar polymers. Compounds present in the D. marginata samples were identified using both gas and liquid chromatography/mass spectrometry (GC/MS and HPLC/MS), assisted by computational methods. It was possible to unequivocally identify 22 emerging contaminants with GC/MS, and 16 substances with HPLC/MS

Solid state structure of sodium β-1-thiophenyl glucuronate identifies 5-coordinate sodium with three independent glucoronates

Glucuronic acid is a key component of the glycosaminoglycans (GAGs) Chrondroitin Sulfate (CS), Heparin/Heparan sulfate (HS) and Hyaluronic Acid (HA), as well an important metabolite derivative. In biological systems the carboxylate of uronic acids in GAGs is involved in important H-binding interactions, and the role of metal coordination, such as sodiated systems, has indications associated with a number of biological effects, and physiological GAG-related processes. In synthetic approaches to GAG fragments, thioglycoside intermediates, or derivatives from these, are commonly employed. Of the reported examples of sodium coordination in carbohydrates, 6-coordinate systems are usually observed often with water ligands involved, Herein we report an unexpected 5-coordinate sodiated GlcA crystal structure of the parent GlcA, but as a thioglucoside derivative, whose crystal coordination differs from previous examples, with no involvement of water as a ligand and containing a distorted trigonal bypramidal sodium with each GlcA having five of 6 oxygens sodium-coordinated

Genomic Analyses of Polysaccharide Utilization in Marine Flavobacteriia

Marine algae convert a substantial fraction of fixed carbon dioxide into various polysaccharides. Flavobacteriia that are specialized on algal polysaccharide degradation feature genomic clusters termed polysaccharide utilization loci (PULs). Since knowledge on extant PUL diversity is sparse, we sequenced the genomes of 53 North Sea Flavobacteriia. We obtained 400 PULs, suggesting usage of a large array of polysaccharides, including laminarin, A A /-- and A A -mannans, fucose-, xylose-, galactose-, rhamnose- and arabinose-containing substrates, pectins, and chitins. Many of the PULs exhibit new genetic architectures and suggest substrates rarely described for marine environments. The isolates' PUL repertoires often differed considerably within genera, corroborating ecological niche-associated glycan partitioning. Polysaccharide uptake in Flavobacteriia is mediated by SusCD-like transporter complexes. Respective protein trees revealed clustering according to polysaccharide specificities predicted by PUL annotations rather than phylogenetic affiliation. Using the trees, we analyzed expression of SusC/D homologs in multiyear phytoplankton bloom-associated metaproteomes and found indications for profound changes in microbial utilization of laminarin, A A /--glucans, ß-mannan and sulfated xylan. We hence suggest the suitability of SusC/D-like transporter protein expression within heterotrophic bacteria as a proxy for the temporal utilization of discrete polysaccharides

Heterosídeos sintetizados por linhagens de cor e estádios reprodutivos de macroalgas vermelhas dos gęneros Hypnea E Gracilaria /

Orientador: Miguel Daniel NosedaCo-orientadora: Maria Eugęnia Duarte NosedaTese (doutorado) - Universidade Federal do Paraná, Setor de Cięncias Biológicas, Programa de Pós-Graduaçăo em Bioquímica. Defesa: Curitiba, 2006Inclui bibliografi

Halogenated organic molecules of Rhodomelaceae origin: chemisty and biology

1引言 2。评论 3。分类 4，结构和发生 4.1。卤化单萜 4.2。卤化倍半萜 4.2.1。Bisabolane倍半萜 4.2.2。Brasilane倍半萜 4.2.3。Chamigrane倍半萜 4.2.4。Cuparane倍半萜 4.2.5。桉和6,8 - Cycloeudesmane倍半萜 4.2.6。Laurane和Cyclolaurane倍半萜 4.2.7。Snyderane倍半萜 4.2.8。倍半萜与新碳骨架 4.2.9。杂倍半萜 4.2.10。卤化倍半萜的发生概要 4.3。卤代烷二萜 4.3.1。Irieane二萜 4.3.2。Labdane二萜 4.3.3。Parguerane，Isoparguerane，Neoparguerane和Pimarane二萜 4.3.4。其他二萜与新的或少见报道骷髅 4.4。卤化三萜类/聚醚 4.4.1。三萜类持有2,7 - 二氧杂双环[4.4.0]癸烷骨架 4.4.2。三萜类持有一个2,8 - 二氧杂双环[5.4.0]十一烷骨架 4.4.3。三萜类持有对称元素（S） 4.5。卤化Nonterpenoid C15-内酯（ACGS） 4.5.1。线性ACGS 4.5.2。五元环醚类（四氢呋喃ACGS，THF ACGS）的ACGS 4.5.3。国际清算银行 - 四氢呋喃类（双四氢呋喃ACGS）的ACGS 4.5.4。的2,6 - 二氧杂双环[3.3.0]辛烷类的ACGS 4.5.5。六元环醚类（四氢吡喃ACGS，THP ACGS）的ACGS 4.5.6。的2,7 - 二氧杂双环[4.3.0]壬烷类ACGS 4.5.7。七元环醚类ACGS 4.5.8。八元环醚类ACGS 4.5.9。九和十元环醚类的ACGS 4.5.10。十二元环醚类ACGS 4.5.11。该Maneonene和Isomaneonene类的ACGS 4.5.12。支ACGS 4.5.13。杂项ACGS 4.6。卤代吲哚 4.7。卤化酚类/芳烃 4.8。其他卤化有机分子 4.9。摘要以卤化有机分子的发生 5，化学分类学意义 6。合成 6.1。倍半萜的合成 6.1.1。Chamigrane倍半萜的合成 6.1.2。Laurane和Snyderane倍半萜的合成 6.1.3。倍半萜的合成与新型碳骨架 6.2。二萜的合成 6.3。三萜类化合物的合成 6.3.1。Thyrsiferol及其衍生物的合成 6.3.2。（+） - Intricatetraol的合成 6.4。C15-内酯的合成（ACGS） 6.4.1。ACGS含四氢呋喃结构单元的合成 6.4.2。七元环ACGS的合成 6.4.3。ACGS含有八元环的环状醚的芯体的合成 6.4.4。ACGS含九元环的环状醚的芯体的合成 6.4.5。Maneonene和Isomaneonene ACGS的合成 6.5。Bromoindoles的合成 6.6。溴苯酚的合成 7，生物合成 7.1。倍半萜的生物合成 7.2。C15-内酯的生物合成 8，生物活性和功能 8.1。生物活性 8.1.1。细胞毒活性 8.1.2。抗菌活性 8.1.3。抗真菌活性 8.1.4。抗病毒活性 8.1.5。酶抑制活性 8.1.6。自由基清除活性 8.2。生物功能 8.2.1。拒食作用 8.2.2。杀虫活性 8.2.3。防污活动 8.2.4。化感活性 8.3。杂项活动 8.4。生物活性和功能的概要 9。为未来的发现与展望结语 </ul

Seaweeds : a traditional ingredients for new gastronomic sensation

Seaweeds have a long tradition in Asian cuisine. In Canada and US, seaweed consumption is mostly limited to sushi and other imported Asian dish. However, seaweeds are well recognized for their richness in several nutrients such as fiber, protein and minerals. But what is limiting seaweed and seaweed derived ingredients utilization in home cooking? Finding fresh seaweeds within inland cities is one limiting step but also the seaweed marketing need to propel the image that seaweed are not only nutritive but can bring flavor and texture in cuisine dish. With the rise of TV cooking shows, blogs and online recipes hosted by several renowned chefs, it is now time to bring seaweed in the spotlight. The aim of this review is to look at seaweeds to support a wider use in culinary applications for their nutritional contribution but also from a sensory perspective

POPULATION GENETICS AND DESICCATION STRESS OF PORPHYRA UMBILICALIS KÜTZING IN THE GULF OF MAINE

The red alga Porphyra umbilicalis Kützing is an ecologically and economically important marine macroalga in the Northern Atlantic. Porphyra umbilicalis has a broad distribution within the North Atlantic. In the Northeast Atlantic, it is dioecious and reproduces both sexually and asexually, while in the Northwest Atlantic only asexual reproduction has been observed. As a high intertidal alga, P. umbilicalis regularly experiences desiccation and rehydration cycles with the tidal cycles, so it has high tolerance towards various abiotic stresses. The present work attempts to understand the population structure in asexual populations of P. umbilicalis in the Gulf of Maine by applying putative single nucleotide polymorphisms (SNP) markers developed from transcriptome data (Chapter 1). In order to understand the desiccation tolerance of P. umbilicalis, the contents of putative compatible solutes were measured and the genes involved in the synthesis of these solutes were analyzed in response to desiccation and rehydration treatments (Chapter 2). In addition, a comparative transcriptomic analysis was performed using P. umbilicalis under fresh, dehydrated, desiccated and rehydrated conditions in order to gain insights into the mechanisms of its desiccation tolerance in responses to water loss and water gain (Chapter 3). My work represents the first attempt to develop a suitable bioinformatic pipeline for RNA-seq to detect SNP markers for the red alga P. umbilicalis and to apply these SNP markers for population analysis. The compatible solutes study verifies the occurrences of nanomolar concentrations of trehalose in P. umbilicalis for the first time and identifies additional genes, possibly encoding trehalose phosphate synthases. The transcriptome study suggested distinct molecular responses may occur during dehydration and desiccation and confirmed that the rehydration-induced responses play an important role in the mechanisms of desiccation tolerance in P. umbilicalis