For Publishers
DiscoveryMetadataPeer reviewHostingPublishing
For Researchers
JoinPublishReviewCollect
Register
Blog
About
Search
Advanced search
My ScienceOpen
Search
For Publishers
For Researchers
Blog
About
8
views
120
references
 Top references
cited by
18
    
0 reviews
 Review
0
comments
 Comment
0
recommends
+1 Recommend
0 collections
    0
    shares
      316
      similar
       All similar
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Xanthones of Lichen Source: A 2016 Update

      review-article

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          An update of xanthones encountered in lichens is proposed as more than 20 new xanthones have been described since the publication of the compendium of lichen metabolites by Huneck and Yoshimura in 1996. The last decades witnessed major advances regarding the elucidation of biosynthetic schemes leading to these fascinating compounds, accounting for the unique substitution patterns of a very vast majority of lichen xanthones. Besides a comprehensive analysis of the structures of xanthones described in lichens, their bioactivities and the emerging analytical strategies used to pinpoint them within lichens are presented here together with physico-chemical properties (including NMR data) as reported since 1996.

          Related collections

          Most cited references120

          • Record: found
          • Abstract: found
          • Article: not found

          Dehalococcoides mccartyi gen. nov., sp. nov., obligately organohalide-respiring anaerobic bacteria relevant to halogen cycling and bioremediation, belong to a novel bacterial class, Dehalococcoidia classis nov., order Dehalococcoidales ord. nov. and family Dehalococcoidaceae fam. nov., within the phylum Chloroflexi.

          Frank Löffler, Jun Yan, Kirsti M Ritalahti … (2013)
          Six obligately anaerobic bacterial isolates (195(T), CBDB1, BAV1, VS, FL2 and GT) with strictly organohalide-respiring metabolisms were obtained from chlorinated solvent-contaminated aquifers, contaminated and uncontaminated river sediments or anoxic digester sludge. Cells were non-motile with a disc-shaped morphology, 0.3-1 µm in diameter and 0.1-0.2 µm thick, and characteristic indentations on opposite flat sides of the cell. Growth occurred in completely synthetic, reduced medium amended with a haloorganic electron acceptor (mostly chlorinated but also some brominated compounds), hydrogen as electron donor, acetate as carbon source, and vitamins. No other growth-supporting redox couples were identified. Aqueous hydrogen consumption threshold concentrations were <1 nM. Growth ceased when vitamin B(12) was omitted from the medium. Addition of sterile cell-free supernatant of Dehalococcoides-containing enrichment cultures enhanced dechlorination and growth of strains 195 and FL2, suggesting the existence of so-far unidentified stimulants. Dechlorination occurred between pH 6.5 and 8.0 and over a temperature range of 15-35 °C, with an optimum growth temperature between 25 and 30 °C. The major phospholipid fatty acids were 14 : 0 (15.7 mol%), br15 : 0 (6.2 mol%), 16 : 0 (22.7 mol%), 10-methyl 16 : 0 (25.8 mol%) and 18 : 0 (16.6 mol%). Unusual furan fatty acids including 9-(5-pentyl-2-furyl)-nonanoate and 8-(5-hexyl-2-furyl)-octanoate were detected in strains FL2, BAV1 and GT, but not in strains 195(T) and CBDB1. The 16S rRNA gene sequences of the six isolates shared more than 98 % identity, and phylogenetic analysis revealed an affiliation with the phylum Chloroflexi and more than 10 % sequence divergence from other described isolates. The genome sizes and G+C contents ranged from 1.34 to 1.47 Mbp and 47 to 48.9 mol% G+C, respectively. Based on 16S rRNA gene sequence comparisons, genome-wide average nucleotide identity and phenotypic characteristics, the organohalide-respiring isolates represent a new genus and species, for which the name Dehalococcoides mccartyi gen. nov., sp. nov. is proposed. Isolates BAV1 ( = ATCC BAA-2100  = JCM 16839  = KCTC 5957), FL2 ( = ATCC BAA-2098  = DSM 23585  = JCM 16840  = KCTC 5959), GT ( = ATCC BAA-2099  = JCM 16841  = KCTC 5958), CBDB1, 195(T) ( = ATCC BAA-2266(T)  = KCTC 15142(T)) and VS are considered strains of Dehalococcoides mccartyi, with strain 195(T) as the type strain. The new class Dehalococcoidia classis nov., order Dehalococcoidales ord. nov. and family Dehalococcoidaceae fam. nov. are described to accommodate the new taxon.
          Article 0 comments Cited 149 times – based on 0 reviews     Review now
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Bacterial communities associated with the lichen symbiosis.

            Scott T. Bates, Garrett Cropsey, J. Gregory Caporaso … (2011)
            Lichens are commonly described as a mutualistic symbiosis between fungi and "algae" (Chlorophyta or Cyanobacteria); however, they also have internal bacterial communities. Recent research suggests that lichen-associated microbes are an integral component of lichen thalli and that the classical view of this symbiotic relationship should be expanded to include bacteria. However, we still have a limited understanding of the phylogenetic structure of these communities and their variability across lichen species. To address these knowledge gaps, we used bar-coded pyrosequencing to survey the bacterial communities associated with lichens. Bacterial sequences obtained from four lichen species at multiple locations on rock outcrops suggested that each lichen species harbored a distinct community and that all communities were dominated by Alphaproteobacteria. Across all samples, we recovered numerous bacterial phylotypes that were closely related to sequences isolated from lichens in prior investigations, including those from a lichen-associated Rhizobiales lineage (LAR1; putative N(2) fixers). LAR1-related phylotypes were relatively abundant and were found in all four lichen species, and many sequences closely related to other known N(2) fixers (e.g., Azospirillum, Bradyrhizobium, and Frankia) were recovered. Our findings confirm the presence of highly structured bacterial communities within lichens and provide additional evidence that these bacteria may serve distinct functional roles within lichen symbioses.
            Article 0 comments Cited 117 times – based on 0 reviews     Review now
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Current approaches and challenges for the metabolite profiling of complex natural extracts.

              Jean-Luc Wolfender, Guillaume Marti, Aurélien Thomas … (2015)
              Metabolite profiling is critical in many aspects of the life sciences, particularly natural product research. Obtaining precise information on the chemical composition of complex natural extracts (metabolomes) that are primarily obtained from plants or microorganisms is a challenging task that requires sophisticated, advanced analytical methods. In this respect, significant advances in hyphenated chromatographic techniques (LC-MS, GC-MS and LC-NMR in particular), as well as data mining and processing methods, have occurred over the last decade. Together, these tools, in combination with bioassay profiling methods, serve an important role in metabolomics for the purposes of both peak annotation and dereplication in natural product research. In this review, a survey of the techniques that are used for generic and comprehensive profiling of secondary metabolites in natural extracts is provided. The various approaches (chromatographic methods: LC-MS, GC-MS, and LC-NMR and direct spectroscopic methods: NMR and DIMS) are discussed with respect to their resolution and sensitivity for extract profiling. In addition the structural information that can be generated through these techniques or in combination, is compared in relation to the identification of metabolites in complex mixtures. Analytical strategies with applications to natural extracts and novel methods that have strong potential, regardless of how often they are used, are discussed with respect to their potential applications and future trends.
              Article 0 comments Cited 113 times – based on 0 reviews     Review now
                Bookmark
                All references

                Author and article information

                Contributors
                Derek J. McPhee: Role: Academic Editor
                Journal
                Journal ID (nlm-ta): Molecules
                Journal ID (iso-abbrev): Molecules
                Journal ID (publisher-id): molecules
                Title: Molecules
                Publisher: MDPI
                ISSN (Electronic): 1420-3049
                Publication date (Electronic): 02 March 2016
                Publication date Collection: March 2016
                Volume: 21
                Issue: 3
                Electronic Location Identifier: 294
                Affiliations
                Laboratoire de Pharmacognosie, Equipe PNSCM, (ISCR UMR CNRS 6226), Faculté des Sciences Pharmaceutiques et Biologiques, 2 Avenue du Professeur Léon Bernard, 35043, Rennes Cédex, France; pierre.lepogam-alluard@ 123456univ-rennes1.fr
                Author notes
                [* ]Correspondence: joel.boustie@ 123456univ-rennes1.fr ; Tel.: +33-0223-237-840
                Article
                Publisher ID: molecules-21-00294
                DOI: 10.3390/molecules21030294
                PMC ID: 6273661
                PubMed ID: 26950106
                SO-VID: e9a25f68-7951-47bf-97ca-db6d71a6a3ec
                Copyright © © 2016 by the authors.
                License:

                Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons by Attribution (CC-BY) license ( http://creativecommons.org/licenses/by/4.0/).

                History
                Date received : 25 January 2016
                Date accepted : 23 February 2016
                Categories
                Subject: Review

                Keywords: biosynthesis,polyketides,fungi,nmr spectroscopy,bioactivity,lichexanthone,islandicin,thiomelin,secalonic acids
                Data availability:
                Keywords: biosynthesis, polyketides, fungi, nmr spectroscopy, bioactivity, lichexanthone, islandicin, thiomelin, secalonic acids

                Comments

                Comment on this article

                scite_

                Similar content316

                See all similar

                Cited by18

                See all cited by

                Most referenced authors1,421

                See all reference authors