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PubMed2004

Molecular phylogenetics of the Meteoriaceae s. str.: focusing on the genera Meteorium and Papillaria.

In order to delimit and understand the evolution of the Meteoriaceae, we provide phylogenetic analyses using the internal transcribed spacer 2 (ITS2) of nuclear ribosomal DNA in combination with two plastid markers, trnL-F and psbT-H. In contrast to the widely used trnL-F region, the psbT-H gene cluster, coding for proteins of photosystem II, has been rarely used to address systematic questions among the different land plant lineages. To overcome the problem of potential ambiguous alignments of non-coding DNA regions, the data were independently analyzed using direct optimization. The comparison and evaluation of the obtained results showed that the inferred cladograms based on the different phylogenetic approaches are very similar, with only minor differences. In combination with morphological characters, generic relationships as well as taxonomic and nomenclatural problems, especially regarding the key genera Meteorium and Papillaria are discussed in detail. New insights into generic relationships of the Meteoriaceae are provided, such as the exclusion of the monospecific southern South American genera Ancistrodes and Cryphaeophilum, which are subsequently transferred to the Hookeriaceae and Cryphaeaceae, respectively. Phylogenetic reconstructions using maximum likelihood as well as parsimony approaches reveal that at the familial level the Meteoriaceae s. l. are polyphyletic, if the formerly recognized "Trachypodaceae" are considered as a separate family. Based on our results we favor the synonym of the Trachypodaceae with the Meteoriaceae.

Bryopsida↗
PubMed2006

Systematics and morphological evolution within the moss family Bryaceae: a comparison between parsimony and Bayesian methods for reconstruction of ancestral character states.

The Bryaceae are a large cosmopolitan moss family including genera of significant morphological and taxonomic complexity. Phylogenetic relationships within the Bryaceae were reconstructed based on DNA sequence data from all three genomic compartments. In addition, maximum parsimony and Bayesian inference were employed to reconstruct ancestral character states of 38 morphological plus four habitat characters and eight insertion/deletion events. The recovered phylogenetic patterns are generally in accord with previous phylogenies based on chloroplast DNA sequence data and three major clades are identified. The first clade comprises Bryum bornholmense, B. rubens, B. caespiticium, and Plagiobryum. This corroborates the hypothesis suggested by previous studies that several Bryum species are more closely related to Plagiobryum than to the core Bryum species. The second clade includes Acidodontium, Anomobryum, and Haplodontium, while the third clade contains the core Bryum species plus Imbribryum. Within the latter clade, B. subapiculatum and B. tenuisetum form the sister clade to Imbribryum. Reconstructions of ancestral character states under maximum parsimony and Bayesian inference suggest fourteen morphological synapomorphies for the ingroup and synapomorphies are detected for most clades within the ingroup. Maximum parsimony and Bayesian reconstructions of ancestral character states are mostly congruent although Bayesian inference shows that the posterior probability of ancestral character states may decrease dramatically when node support is taken into account. Bayesian inference also indicates that reconstructions may be ambiguous at internal nodes for highly polymorphic characters.

Bayes Theorem↗
PubMed2002

Non-AUG translation initiation of mRNA encoding plastid-targeted phage-type RNA polymerase in Nicotiana sylvestris.

A third nuclear gene encoding a bacteriophage T7-type RNA polymerase, NsRpoT-C, was isolated and characterized from Nicotiana sylvestris. The gene, NsRpoT-C, consists of 21 exons and 20 introns and encodes a polypeptide of 977 amino acid residues. The predicted NsRpoT-C protein shows the highest identity (72% amino acid identity) with Arabidopsis thaliana RpoT;3 which is a plastid-targeted protein. Surprisingly, comparison of the deduced amino acid sequence of NsRpoT-C with that of A. thaliana RpoT;3 predicted that the NsRpoT-C starts at a CUG triplet, a rare translation initiation codon. Transient expression assays in protoplasts from tobacco leaves demonstrated that the putative N-terminal transit peptide of NsRpoT-C encodes a targeting signal directing the protein into chloroplasts. This strongly suggests that NsRpoT-C functions as an RNA polymerase transcribing plastid-encoded genes. We have designated this protein NsRpoTp.

Amino Acid Sequence↗
PubMed2001

Characterization of two genes, Sig1 and Sig2, encoding distinct plastid sigma factors(1) in the moss Physcomitrella patens: phylogenetic relationships to plastid sigma factors in higher plants.

We isolated the cDNA for a sigma factor from the moss Physcomitrella patens, which possesses unusually large N-terminal extension and the conserved subdomains 1.2-4.2. Phylogenetic analyses indicated that this novel sigma factor and PpSIG1*(2), a plastid sigma factor previously identified from Physcomitrella, were classified into SigA and SigB groups, two major classes of higher plant plastid sigma factors, respectively. According to the nomenclature recently proposed, we renamed PpSIG1* into PpSIG2, and named the novel sigma factor PpSIG1. A transient expression assay using a green fluorescent protein showed that the N-terminal region of PpSIG1 acts as a chloroplast-targeting signal. Reverse transcription-PCR experiments showed that light induces the expression of the Sig1 and Sig2 genes encoding PpSIG1 and PpSIG2, respectively. Thus, PpSIG1 and PpSIG2 are likely plastid sigma factors regulating plastid gene expression in response to light signals.

Amino Acid Sequence↗
PubMed1998

Sequences of rDNA internal transcribed spacers from the chloroplast DNA of 26 bryophytes: properties and phylogenetic utility.

We determined the sequence of the region of the chloroplast DNA inverted repeat spanning from the 3'-terminus of the 23S rRNA gene to the 5'-terminus of the tRNA[Arg](ACG) gene (about 700 bp) from 25 bryophytes and from the charophycean alga Chara australis. Phylogenetic analysis of these sequences using the neighbor-joining method suggests an early dichotomy of bryophytes and their paraphyly relative to the tracheophyte lineage. A monophyly of liverworts (Marchantiidae plus Jungermanniidae), a deep divergence of Metzgeriales among Jungermanniidae and a close affinity of the two subclasses of mosses, Sphagnidae and Andreaeidae, are evident. The branching pattern observed is consistent with the phylogenetic distribution of several prominent indels observed in the alignment.

Base Sequence↗
PubMed2001

Hydroquinone derivatives and monoterpenoids from the Neotropical liverwort Plagiochila rutilans.

The structure of a prenylbenzene derivative isolated previously from a Cuban specimen of the liverwort Plagiochila rutilans is revised to 2-methoxy-6-prenylhydroquinone. The hydroquinone was observed as a prominent component of the NMR and GC-MS fingerprints of five recent specimens of the liverwort from Bolivia, Brazil and Costa Rica. The corresponding quinone was observed as a minor component. Two new methylated derivatives of the hydroquinone were observed as prominent components in one specimen from Bolivia; these were isolated, characterized, and their structures elucidated as 2-methoxy-1-O-methyl-6-prenylhydroquinone and 2-methoxy-4-O-methyl-6-prenylhydroquinone using 1H NMR spectroscopy. The liverwort has a strong peppermint-like odour that is caused by the presence of several menthane monoterpenoids, including notably pulegone, menthone, isomenthone. terpinolene and limonene. One of the Costa Rican specimens contained considerable amounts of the new lactone 3,7-dimethyl-2,6-octadien-1,6-olide as the principal monoterpenoid in place of pulegone. Two Costa Rican specimens distinguished morphologically as Plagiochila standleyi (a taxon closely related to P. rutilans and reduced elsewhere to a variety of that species) are characterized by large amounts of 3-hydroxy-4'-methoxybibenzyl. P. standleyi was also reported to have a peppermint-like odour in the field. Menthane monoterpenoids were again responsible but in this case the major components were limonene, beta-phellandrene, alpha-terpinene and the endoperoxide ascaridole.

Benzene Derivatives↗
PubMed2001

Volatile constituents in mosses (Musci).

The essential oils of mosses of the genera Mnium, Plagiomnium, Homalia, Plagiothecium and Taxiphyllum (Musci) have been investigated by gas chromatography and mass spectrometry. The new sesquiterpenes (+)-10-epi-muurola-4,11-diene and 10,11-dihxdro-alpha-cuparenone were isolated by preparative gas chromatography and identified as major constituents of the hydrodistillation products of Mnium hornmum (Hedw.) using NMR and mass spectrometry. In addition, (+)-dauca-8,11-diene and two new butenolides, 3,4,5-trimethyl-5-pentyl-5H-furan-2-one and 3.4-dimethyl-5-pentyl-5H-furan-2-one were identified as constituents in Plagiomnium undulatum (Hedw.) T. Kop. Although the amounts of volatiles present in the investigated mosses are generally smaller than in liverworts, the spectrum of terpenoid compounds is similar. The investigated mosses also generate aliphatic compounds of greater abundance and structural variety.

Bryopsida↗
PubMed2001

3-O-methyl-D-galactose residues in lycophyte primary cell walls.

Acid hydrolysis of cell wall-rich material from young leaves of the lycophyte Selaginella apoda (L.) Spring yielded substantial amounts of 3-O-methyl-D-galactose (1) in addition to the usual major monosaccharides (glucose, galactose, arabinose, xylose and galacturonic acid). The yield of 1 approximately equalled that of galacturonic acid. Compound 1 was identified as 3-O-methylgalactose by its 1H and 13C NMR spectra, and shown to be the D-enantiomer by its susceptibility to D-galactose oxidase. Compound 1 was detected in acid hydrolysates of the alcohol-insoluble residues from young leaves of all lycophytes tested, both homosporous (Lycopodium, Huperzia and Diphasiastrum) and heterosporous (Selaginella). It was not detectable in the charophyte green algae Coleochaete scutata, Chara coralina or Klebsormidium flaccidum, any bryophytes [a hornwort (Anthoceros), four liverworts and three mosses], or any euphyllophytes [a psilopsid (Psilotum), a horsetail (Equisetum), eusporangiate and leptosporangiate ferns, the gymnosperm Gnetum, and diverse angiosperms]. A high content of 1 is thus an autapomorphy of the lycophytes.

Bryopsida↗
PubMed2003

First detection of a chloroperoxidase in bryophytes.

Chlorinated cyclic bisbibenzyls of the isoplagiochin type are the first verified halometabolites from bryophytes. They could be obtained by in vitro chlorination of isoplagiochin C with chloroperoxidase from Caldariomyces fumago. Furthermore, an enzyme of this type was detected for the first time in bryophytes namely in the liverwort Bazzania trilobata using the monochlorodimedon assay.

Bryopsida↗
PubMed2003

Effects of seven pure flavonoids from mosses on germination and growth of Tortula muralis HEDW (Bryophyta) and Raphanus sativus L (Magnoliophyta).

Dried mosses (five moss species) were progressively extracted and subjected to a four-step Craig distribution. Seven pure flavonoids were isolated and identified. The flavonoids were the flavones apigenin, apigenin-7-O-triglycoside, lucenin-2, luteolin-7-O-neohesperidoside, saponarine and vitexin; and the biflavonoid bartramiaflavone and they were submitted to biological tests. The tests were performed in vitro on spore germination and protonemal growth of the moss Tortula muralis and on seed germination and root growth of Raphanus sativus. Flavonoids caused a decrease in the percentage of spore germination, protonemal development and root growth. In addition they caused morphological alterations, such as forked tips, swollen apices, rounded cells and early formation of brood cells in the protonemata. Data were discussed in relation to the presence of allelochemicals in mosses.

Brassica↗
PubMed1997

Betaine lipids and zwitterionic phospholipids in plants and fungi.

Of spermatophytes, ferns, mosses, algae, lichens and fungi, 110 species not analysed so far were examined for diacylglyceryl-N,N,N-trimethylhomoserine (DGTS), diaclyglycerylhydroxymethyl-N,N,N-trimethyl-beta-alanine (DGTA), phosphatidylcholine (PC) and phosphatidylethanolamine (PE) by TLC by using Dragendorff's and molybdenum-blue reagents for detection. The limit of detection was 0.5 microgram per mg or 0.05 weight % of total lipid. The results reveal that betaine lipids are present exclusively in non-flowering plants, including lichens and fungi and, hence, are produced by autotrophic, as well as heterotrophic organisms. DGTS in small amounts is typical of some Rhodophytes, and in appreciable amounts, of vascular cryptogamic plants and some higher fungi. Estimation of the amounts of DGTS and PC in 29 different species reveal that the total amount of zwitterionic lipids varies considerably amongst organisms. No general correlation could be found for the amounts of DGTS and PC, although Rhodophytes contain traces of DGTS but high amounts of PC. On the basis of these results and the presently available data, the natural distribution of the betaine lipids DGTS, DGTA and diacylglycerylcarboxy-N-hydroxymethyl-choline (DGCC) is discussed. In terms of biochemical evolution, the capacity for the formation of DGTS might have been acquired first and, in organisms of the 'DGTS branch', kept until the present time. The formation of DGTA and DGCC might have evolved at a later stage of development in organisms of the 'DGTA-DGCC branch'.

Betaine↗
PubMed1999

Antibacterial activity of pure flavonoids isolated from mosses.

Seven pure flavonoids were isolated and identified from five moss species. The flavonoids were the flavones apigenin, apigenin-7-O-triglycoside, lucenin-2, luteolin-7-O-neohesperidoside, saponarine and vitexin; and the biflavonoid bartramiaflavone. Some of these flavonoids were shown to have pronounced antibacterial effects against Enterobacter cloaceae, E. aerogenes and Pseudomonas aeruginosa (minimal bacteriostatic concentration MIC in the range of 4-2048 micrograms/ml). Because of their antibacterial spectrum mainly active against Gram negative bacterial strains, responsible for severe opportunistic infections and resistant to common antibacterial therapy, these flavonoids may be important tools in antibacterial strategies.

Anti-Bacterial Agents↗
PubMed2002

Poorly humified peat as an adsorbent for metals in wastewater.

Metal adsorption and surface charge determinations were performed previously on well-characterised Sphagnum and Carex peat samples. The aim of this investigation was to determine metal adsorption from complex wastewaters onto these peat samples and compare it to the adsorption onto peat granules, clinoptilolite, glauconite and a flue dust from steel production. A sulphide mine leachate, a landfill leachate and a laundry wastewater were chosen, giving a variation in pH, ionic strength, total organic carbon and concentrations of metals. Metal adsorption was determined in batch and column experiments. The wastewater composition was of great importance for metal removal efficiency, mainly due to the difference in dominating metal species. In the sulphide mine leachate, containing free metal ions, a high metal adsorption was observed onto both peat and inorganic adsorbents. In the landfill leachate the metals formed carbonate and organic complexes and a low metal removal was achieved. Contrary to the leachates, the laundry wastewater contained suspended particles. The high amount of metals removed, 80% of the Cu and 30-60% of the Zn concentration, was probably withdrawn bound to the particle fraction. The highest removal of metal ions was obtained in the sulphide mine leachate with Carex peat, removing 97-99% of the Zn and 85-100% of the Cu content. The Sphagnum peat sample removed 37-77% of the Zn and 80-100% of the Cu content. The differences found between Sphagnum and Carex peat were attributed to the original chemistry of the plant material and the habitat conditions at the time of peat formation. Generally, the combination of glauconite or clinoptilolite with the peat samples in column experiments gave a minor improvement in metal removal.

Adsorption↗
PubMed2002

Copper and zinc adsorption onto poorly humified Sphagnum and Carex peat.

Peat generally has a high adsorption capacity and has been suggested as an adsorbent for metals in polluted waters. However, the adsorption potential of peat can be expected to be strongly dependent on the chemical properties of the water. In this study, the effect of pH, ionic strength (CaCl2 and NaCl concentrations), and metal concentration on Cu and Zn adsorption onto poorly humified Sphagnum and Carex peat was investigated in batch experiments using a fractional factorial experimental design. The pH value was varied between 4 and 8, the CaCl2 and NaCl concentrations between 1.2-6.2 and 0.4-43 mM, respectively, and the Cu and Zn concentrations between 0.05 and 0.5 mM. The amount of Zn adsorbed increased more with increasing pH than the amount of Cu adsorbed. The effect of NaCl/CaCl2 concentration was minor. It was found that Zn adsorption in particular, but also Cu adsorption, increased more with pH onto Carex peat than onto Sphagnum peat. In the pH interval 4-8, the removal of Zn from the solution increased from 0% to 80% using Carex peat and from 10% to 65% using Sphagnum peat as the adsorbent. The Carex peat sample decreased the Cu concentration by 80% at pH 4 and by 95% at pH 8 and for Sphagnum peat a decrease of 85% was maintained in the pH range investigated. The differences between Sphagnum and Carex peat were attributed to the habitat conditions at the time of peat formation. Carex peat has higher ash, nitrogen and sulphur concentrations, while Sphagnum peat contains a higher amount of uronic acid. In treating polluted waters with peat, a higher degree of metal removal can be expected at high pH values than at low. The removal of Cu, which has a high affinity to the peat surface, was less dependent on pH than Zn removal. Poorly humified Carex peat should be chosen in treating wastewaters high in pH.

Adsorption↗
PubMed2002

Uptake and release of zinc by aquatic bryophytes (Fontinalis antipyretica L. ex. Hedw.).

The zinc uptake and posterior release by an aquatic bryophyte-Fontinalis antipyretica L. Ex Hedw.--was experimentally studied in laboratory exposing the plants to different zinc concentrations in the range, 1.0-5.0 mg 1(-1), for a 144 h contamination period, and then exposed to metal-free water for a 120 h decontamination period. The experiments were carried out in perfectly mixed contactors at controlled illumination, using mosses picked out in February 1997, with a background initial zinc concentration of 263 mg g(-1) (dry wt.). A first-order mass transfer kinetic model was fitted to the experimental data to determine the uptake and release constants, k1 and k2, the zinc concentration in mosses at the end of the uptake period, C(mu), and at the equilibrium, for the contamination and decontamination stages, C(me) and C(mr), respectively. A bioconcentration factor, BCF = k1 /k2 (zinc concentration in the plant, dry wt./zinc concentration in the water) was determined. A biological elimination factor defined as BEF = 1 - C(mr)/C(mu) was also calculated. BCF decreases from about 4500 to 2950 as Zn concentration in water increases from 1.05 to 3.80mg 1(-1). BEF is approximately constant and equal to 0.80. Comparing Zn and Cu accumulation by Fontinalis antipyretica, it was concluded that the uptake rate for Zn (145 h(-1)) is much lower than for Cu (628 h(-1)) and the amount retained by the plant decreased by a factor of about seven.

Bryopsida↗
PubMed2000

Lichens and mosses as biomonitors of trace elements in areas with thermal springs and fumarole activity (Mt. Amiata, central Italy).

The contribution of thermal springs and fumaroles to environmental levels of Al, As, B, Cd, Cu, Fe, Hg, Mo, Pb, S, Sb and Zn was evaluated by means of lichens (Parmelia sulcata) and mosses (Hypnum cupressiforme) used as bioaccumulators. Compared to the data reported for unpolluted areas, accumulation of Hg, S and Al was found, with values of Hg and S in the same range as in the vicinity of geothermal power plants. Furthermore, fumaroles turned out to be a significant source of atmospheric arsenic.

Air Pollutants↗
PubMed2002

Biomonitoring metal deposition in Galicia (NW Spain) with mosses: factors affecting bioconcentration.

Three factors (canopy effect, lithology and seasonal variations) that may influence the concentrations of metals in terrestrial mosses were studied. The levels of 17 elements were determined in terrestrial mosses (Scleropodium purum (Hedw.) Limpr, and Hypnum cupressiforme Hedw.) collected from 75 sites in Galicia at two sampling times, in 1995 and 1997. In addition, monthly samples of S. purum were collected throughout a period of one year from four sites in the same area, for analysis of levels of eight elements. The first studied factor, collection of mosses from areas under tree cover, did not influence significantly the levels of the elements analysed. The second factor studied was the dominant lithology in the sampling area (granite, slate and schist). No significant differences were found between samples from sites where granites and slates dominated. Significant differences were found in the levels of Co, Cr, Ni and Mn in both species growing in granite and slate substrate areas when compared with those growing in schist areas. This was also found for Al and Fe in S. purum and for As in H. cupressiforme. The third factor investigated, using the results from the monthly survey, was the seasonal effect. No significant differences were found in the concentrations of all elements in S. purum throughout the year.

Air Pollutants↗