Desiccation tolerance in the Antarctic moss Sanionia uncinata

BACKGROUND: One of the most extreme environments on our planet is the Maritime Antarctic territory, due to its low-water availability, which restricts the development of plants. Sanionia uncinata Hedw. (Amblystegiaceae), the main colonizer of the Maritime Antarctic, has effective mechanisms to tolerate this environment. It has been described that the tolerance to desiccation is mediated by the hormone abscisic acid (ABA), antioxidants systems, accumulation of compatible solutes and proteins of the late embryogenesis abundant (LEA). However, to date, these mechanisms have not been described in S. uncinata. Therefore, in this work, we postulate that the tolerance to desiccation in the Antarctic moss S. uncinata is mediated by the accumulation of ABA, the osmolytes proline and glycine betaine, and dehydrins (an LEA class 11 proteins). To demonstrate our hypothesis, S. uncinata was subjected to desiccation for 24 h (loss in 95% of water content), and the effects on its physiological, photosynthetic, antioxidant and biochemical parameters were determined. RESULTS: Our results showed an accumulation of ABA in response to water loss, and the activation of protective responses that involves an increment in levels of proline and glycine betaine, an increment in the activity of antioxidant enzymes such as SOD, CAT, APX and POD, and the accumulation of dehydrins proteins. CONCLUSION: The results showed, suggest that S. uncinata is a desiccation-tolerant moss, property mediated by high cellular plasticity regulated by ABA.

Heterologous protein production in the moss Physcomitrella patens

Over the last decades plants have been used for the heterologous production of pharmaceuticals, industrial enzymes and edible vaccines. The moss Physcomitrella patens is considered as an experimental model of choice for basic molecular, cytological and developmental questions in plant biology, as well as an outstanding plant model system for heterologous protein production. Here we use P. patens to produce osmotin, a tobacco protein with fungicidal properties. We have generated a transgenic plant able to synthesize and secrete a biologically active osmotin protein(AU)

Durante las últimas décadas las plantas han sido utilizadas para la producción heteróloga de farmacéuticos, enzimas de uso industrial y vacunas. El musgo Physcomitrella patens es considerado como un modelo de experimentación de elección para abordar preguntas en las áreas de biología molecular, citología y de biología del desarrollo en plantas; así como un excelente sistema modelo para la producción de proteínas heterólogas. En este trabajo se utilizó P. patens para la producción de osmotina, una proteína de tabaco con propiedades fungicidas. Se generó una planta transgénica capaz de sintetizar y secretar osmotina biológicamente activa(AU)

Soluble carbohydrate content variation in Sanionia uncinata and Polytrichastrum alpinum, two Antarctic mosses with contrasting desiccation capacities

BACKGROUND: Cryptogamic vegetation dominates the ice-free areas along the Antarctic Peninsula. The two mosses Sanionia uncinata and Polytrichastrum alpinum inhabit soils with contrasting water availability. Sanionia uncinata grows in soil with continuous water supply, while P. alpinum grows in sandy, non-flooded soils. Desiccation and rehydration experiments were carried out to test for differences in the rate of water loss and uptake, with non-structural carbohydrates analysed to test their role in these processes. RESULTS: Individual plants of S. uncinata lost water 60 % faster than P. alpinum; however, clumps of S. uncinata took longer to dry than those of P. alpinum (11 vs. 5 h, respectively). In contrast, rehydration took less than 10 min for both mosses. Total non-structural carbohydrate content was higher in P. alpinum than in S. uncinata, but sugar levels changed more in P. alpinum during desiccation and rehydration (60-50 %) when compared to S. uncinata. We report the presence of galactinol (a precursor of the raffinose family) for the first time in P. alpinum. Galactinol was present at higher amounts than all other non-structural sugars. CONCLUSIONS: Individual plants of S. uncinata were not able to retain water for long periods but by growing and forming carpets, this species can retain water the longest. In contrast individual P. alpinum plants required more time to lose water than S. uncinata, but as moss cushions they suffered desiccation faster than the later. On the other hand, both species rehydrated very quickly. We found that when both mosses lost 50 % of their water, carbohydrates content remained stable and the plants did not accumulate non-structural carbohydrates during the desiccation prosses as usually occurs in vascular plants. The raffinose family oligosaccarides decreased during desiccation, and increased during rehydration, suggesting they function as osmoprotectors.

A primary assessment of the endophytic bacterial community in a xerophilous moss (Grimmia montana) using molecular method and cultivated isolates

Investigating the endophytic bacterial community in special moss species is fundamental to understanding the microbial-plant interactions and discovering the bacteria with stresses tolerance. Thus, the community structure of endophytic bacteria in the xerophilous moss Grimmia montana were estimated using a 16S rDNA library and traditional cultivation methods. In total, 212 sequences derived from the 16S rDNA library were used to assess the bacterial diversity. Sequence alignment showed that the endophytes were assigned to 54 genera in 4 phyla (Proteobacteria, Firmicutes, Actinobacteria and Cytophaga/Flexibacter/Bacteroids). Of them, the dominant phyla were Proteobacteria (45.9%) and Firmicutes (27.6%), the most abundant genera included Acinetobacter, Aeromonas, Enterobacter, Leclercia, Microvirga, Pseudomonas, Rhizobium, Planococcus, Paenisporosarcina and Planomicrobium. In addition, a total of 14 species belonging to 8 genera in 3 phyla (Proteobacteria, Firmicutes, Actinobacteria) were isolated, Curtobacterium, Massilia, Pseudomonas and Sphingomonas were the dominant genera. Although some of the genera isolated were inconsistent with those detected by molecular method, both of two methods proved that many different endophytic bacteria coexist in G. montana. According to the potential functional analyses of these bacteria, some species are known to have possible beneficial effects on hosts, but whether this is the case in G. montana needs to be confirmed.

Advances of taxol combinatorial biosynthesis / 生物工程学报

Taxol is a kind of isoprenoid with strong anticancer activity. It is difficult to be obtained because of its low concentration in nature, which hinders its application in cancer treatment. Recently, biosynthesis methods for taxol production have attracted more attentions. Several systems including Escherichia coli, Saccharomyces cerevisiae, Physcomitrella patens, Arabidopsis, tomato and ginseng were explored. This review focuses on the advance in biosynthesis of taxol in different systems and features the bottleneck of scale fermentation for producing the intermediates. At the same time some advices for the further were given. At last, the future and character of Physcomitrella patens system used in taxol combinatorial biosynthesis were analyzed based on our lab's research.

Physical factors contributing to the benthic dominance of the alga Caulerpa sertularioides (Caulerpaceae, Chlorophyta) in the upwelling Bahía Culebra, north Pacific of Costa Rica / Factores físicos que contribuyen a la dominancia bentónica del alga Caulerpa sertularioides (Caulerpaceae, Chlorophyta) en la surgencia Bahía Culebra, Pacífico norte de Costa Rica

Caulerpa sertularioides has been spreading in Bahía Culebra, a seasonal upwelling bay in the north Pacific of Costa Rica, since 2001. The survey was carried out from December 2003 to March 2005, in several locations around Bahía Culebra, located inside the Gulf of Papagayo. This study investigated spatial and temporal patterns, percent coverage, monthly growth rate, reproductive adaptations, and morphological variations of frond length and stolon diameter of Caulerpa sertularioides, at different environmental physical and chemical factors at the bay. The alga extended to depths of 23 m on a variety of substrates. The stolons extended quickly, with a maximum growth rate of 31.2 cm month-1. This alga grows mainly by fragmentation of its fronds and stolons; nevertheless it can also reproduce sexually by releasing gametes in the water column. These two modes of spreading promote the adaptation of this opportunistic species to environmental, chemical, and physical changes at this bay. At the same time the alga showed variations in the length of its fronds and stolons, adapting to conditions such as depth and season. Average percent cover and frond density increased during the dry season when the upwelling of nutrients and cold water occurs. In the rainy season the average percent cover and frond density decreased; however there was a peak in September, when high precipitation resulted in runoff into the bay of nutrient-rich waters. The morphological and physiological plasticity of C. sertularioides, in synergy with its predominant clonal propagation and sexual reproduction provided this species with a great adaptability to changes in temperature and nutrient concentration at Bahía Culebra.

Desde el 2001 se ha observado una propagación del alga verde Caulerpa sertularioides en Bahía Culebra, zona de afloramiento costero, en el Pacífico norte de Costa Rica. El muestreo se llevó acabo entre Diciembre 2003 a marzo 2005, en varias localidades de Bahía Culebra. En este estudio se presentan los patrones de distribución, cobertura, tasa mensual de crecimiento, adaptaciones reproductivas y variaciones morfológicas del largo de la fronda y diámetro del estolón de Caulerpa sertularioides, a diferentes factores ambientales físico-químicos en Bahía Culebra. Esta alga se extiende hasta profundidades de 23 m, en una gran variedad de sustratos. Los estolones se extienden rápidamente, con un crecimiento máximo de 31.2 cm mes-1. Esta alga se propaga principalmente por la fragmentación de sus frondas y estolones, así mismo se reproduce sexualmente liberando gametos a la columna de agua. Estos modos de reproducción promueven la adaptación de esta especie oportunista, a los cambios ambientales, tanto químicos, como físicos, de la bahía. Al mismo tiempo esta alga presenta variaciones en el largo de sus frondas y el diámetro del rizoma, adaptándose a diferentes profundidades y condiciones de la época del año. El porcentaje de cobertura y densidad de frondas aumentan durante la época seca, cuando emergen aguas frías y nutrientes por el afloramiento costero. Por otro lado, en la época lluviosa estas medidas decrecen, sin embargo se presenta un pico en setiembre, cuando la precipitación aumenta y llega una carga extra de nutrientes a la bahía por escorrentía. La plasticidad morfológica y fisiológica de C. sertularioides, en sinergia con su propagación clonal, proveen a esta alga con una gran adaptabilidad a los cambios en temperatura y nutrientes de Bahía Culebra.

Biomonitoring of metal deposition by using moss transplant method through Hypnum cupressiforme (Hedw.) in Mussoorie.

Metals Cu, Zn, Cd and Pb were surveyed at 14 sampling sites by using moss Hypnum cupressiforme through active monitoring technique. Samples were transplanted in all four directions of Mussoorie city and were harvested after exposure of four months (representing each season) to analyze metal precipitation and its trend at different sites during 2005. Bioaccumulation ability for metals was evaluated seasonally exhibiting maximum in summer followed by winter and minimum in rainy season. However, at some places Cu shows highly significant values in rainy season in comparison to winter. In case of Zn and Pb significantly different (p < or = 0.05) values were observed between summerand rainy season. Baseline concentration of Cu, Pb and Zn was significantly different at 5% in comparison to other transplant sites. Result indicates Dhanaulti as most polluted location might be due to higher tourist activity and vehicular load, whereas, same was found low at Chamba might be due to place was free from pollution sources or away from in proximity to road and have low human interference. The present study allows us to determine the extent of the area affected by metal precipitation load in different rural and urban areas and abundance of metals in order of Zn > Pb > Cu > Cd.

Isolation and identification of a Pp-LIM only A gene expressed during cold acclimation in Physcomitrella patens / 生物工程学报

Cold acclimation can improve freezing tolerance. Here cDNA amplified fragment length polymorphism (cDNA-AFLP) was used to isolate differentially expressed cDNAs and a Pp-LIM only A cDNA was isolated and identified in the cold acclimation of Physcomitrella patens. Real-time RT-PCR indicated it is obviously up-regulated at 6 h, 12 h, 24 h, 48 h and 72 h after cold acclimation. After comparing the cDNA with the gene sequence, seven introns and eight exons were identified in the cDNA. The cDNA putatively encodes a protein of 345 amino acid residues and only contains one LIM domain which has highly similarity with the PDZ/LIM domains of the protein family in animals. We proposed that Pp-LIM only A be a new gene coding for the LIM-domain containing protein and enhance stability of cell membrane via their effects on cytoskeleton during cold acclimation in P. patens.

Studies on chemical constituents from moss Rhodobryum roseum II / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents from Rhodobryum roseum.</p><p><b>METHOD</b>The compounds were isolated and purified by recrystallization and chromatography with silica gel and sephadex LH-20 column. Their structures were identified by physicochemical properties and spectral analysis.</p><p><b>RESULT</b>Eight compounds were isolated and identified as apigenin (1), quercetin (2), oleanolic acid (3), 2alpha-hydroxyoleanolic acid (4), 2alpha-hydroxyursolic acid (5), protocatechuic acid (6), p-hydroxybenzoic acid (7), p-hydroxycinnamic acid (8).</p><p><b>CONCLUSION</b>Compounds 1-8 were isolated from R. roseum for the first time.</p>

Helicophyllaceae (Bryophyta), nova ocorrência para o Estado do Pará, Brasil / Helicophyllaceae (Bryophyta), a new record to Pará State, Brazil

Helicophyllaceae, família monotípica neotropical, é registrada pela primeira vez no Estado do Pará. Sua única espécie, Helicophyllum torquatum (Hook.) Brid., registrada anteriormente no Estado do Amazonas e que recentemente havia sido excluída da lista de musgos amazônicos, é apresentada como nova ocorrência para toda a Amazônia brasileira.

Novas ocorrências de briófitas para vários estados do Brasil / New records of bryophytes in the states of Brazil

Cento e dezesseis espécies de briófitas são relatadas como novas ocorrências em vários estados do Brasil, sendo 62 de musgos, 53 de hepáticas e uma de antóceros. Estas espécies pertencem a 67 gêneros e 36 famílias. Para cada uma das espécies são apresentados dados quanto à distribuição geográfica no Brasil, localidade-tipo, basiônimo, bem como comentários sobre o substrato e as associações com outras espécies, quando pertinente. As espécies Acrolejeunea heterophylla (Evans) Grolle & Gradst., Brachymenium wrightii var. mnioides (Besch.) Florsch., Cheilolejeunea myriantha (Nees & Mont.) Schust., Cololejeunea nigerica (E.W. Jones) Schust., Lejeunea filipes Spruce, Leucodon julaceus (Hedw.) Sull., Macromitrium clavatum Grout, Plagiochila asplenioides (L.) Dumort., Polytrichum brachymitrium C. Muell. e Pylaisiadelpha tenuirostris (Bruch & Schimp. ex Sull.) Buck estão sendo referidas pela primeira vez para o Brasil.

One hundred and sixteen (116) species of bryophytes are reported as new records for certain Brazilian states, distributed in 62 mosses, 53 liverworts and one hornworts. Those species are distributed among 67 genera and 36 families. Geographical distribution in Brazil, type locality, basyonym, comments on substrate, and about association with other bryophytes, when possible. The species Acrolejeunea heterophylla (Evans) Grolle & Gradst., Brachymenium wrightii var. mnioides (Besch.) Florsch., Cheilolejeunea myriantha (Nees & Mont.) Schust., Cololejeunea nigerica (E.W. Jones) Schust., Lejeunea filipes Spruce, Leucodon julaceus (Hedw.) Sull., Macromitrium clavatum Grout, Plagiochila asplenioides (L.) Dumort., Polytrichum brachymitrium C. Muell. and Pylaisiadelpha tenuirostris (Bruch & Schimp. ex Sull.) Buck are new records for Brazil.

Propiedades funcionales de la fibra del musgo sphagnum magellanicum y su utilización en la formulación de productos de panadería / Functional properties of sphagnum magellanicum fiber and its direct use in formulation of bakery products

Se estudiaron las propiedades funcionales de la fibra del musgo Sphagnum magellanicum. determinandose: la capacidad de absosrción (CAA) y retención de agua (CRA), capacidad de absorción de moléculas orgánicas (CAMO), capacidad de hinchamiento (CH) y capacidad de intercambio catiónico (CIC). Fracciones de tamaño de partícula T1 (1.4mm); (1.0mm); T3 (0.425mm); T4 (0.180mm) fueron analizadas para medir su efecto sobre estas propiedades. Las mejores respuestas de CAA, CRA, CAMO y CH se obtuvieron con T3, con la excepción de la CIC cuyo mejor resultado se obtuvo con T1. Se desarrollo una formulación optimizada de pan enriquecido con fibre de musgo analizando simultaneamente el efecto de cuatro variables independientes: levadura, agente esponjante, fibra de musgo y manteca vegetal sobre la calidad sensorial del pan. La variable más significativa (p<0.05) resultó ser la levadura con participación del 50 por ciento sobre la respuesta. Muestras de pan con fiebre se almacenaron a 20 grados centígrados y 6 grados centígrados para determinar su vida útil. La mejor respuesta de calidad sensorial se obtuvo con las muestras refrigeradas, que permanecieron aptas para su consumo por un tiempo de dos semanas

Diterpenoids from Azorella compacta (Umbelliferae) active on Trypanosoma cruzi

The anti-Trypanosoma cruzi activity of natural products isolated from Azorella compacta was evaluated, with particular emphasis on their effect against intracellular amastigotes. Five diterpenoids from A. compacta derived from mulinane and azorellane were isolated and identified. Only two products, named azorellanol (Y-2) and mulin-11,3-dien-20-oic acid (Y-5), showed trypanocidal activity against all stages of T. cruzi including intracellular amastigotes. At 10 æM, these compounds displayed a strong lytic activity. It ranged from 88.4 ± 0.6 to 99.0 ± 1 percent for all strains and stages evaluate, with an IC50 /18 h values of 20-84 æM and 41-87 æM, respectively. The development of intracellular amastigotes was also inhibited by nearly 60 percent at 25 æM. The trypanocidal molecules Y-2 and Y-5 did show different degrees of cytotoxicity depending on the cell line tested, with an IC50 /24 h ranging from 33.2 to 161.2 æM. We evaluated the effect of diterpenoids against intracellular T. cruzi forms by immunofluorescent identification of a specific membrane molecular marker (Ssp-4 antigen) of the T. cruzi amastigote forms. The accuracy and reproducibility of the measurements were found to be outstanding when examined by confocal microscopy

Purification and characterization of a Ca(2+)-dependent/calmodulin-stimulated protein kinase from moss chloronema cells.

We have demonstrated the presence of a Ca2+-dependent/calmodulin-stimulated protein kinase (PK) in chloronema cells of the moss Funaria hygrometrica. The kinase, with a molecular mass of 70,000 daltons (PK70), was purified to homogeneity using ammonium sulphate fractionation, DEAE-cellulose chromatography, and calmodulin (CaM)-agarose affinity chromatography. The kinase activity was stimulated at a concentration of 50 mM free Ca2+, and was further enhanced 3-5-fold with exogenously added 3-1000 nm moss calmodulin (CaM). Autophosphorylation was also stimulated with Ca2+ and CaM. Under in vitro conditions, PK70 phosphorylated preferentially lysine-rich substrates such as HIIIS and HVS. This PK shares epitopes with the maize Ca2+-dependent/calmodulin-stimulated PK (CCaMK) and also exhibits biochemical properties similar to the maize, lily, and tobacco CCaMK. We have characterized it as a moss CCaMK.

Enhanced expression of a calcium-dependent protein kinase from the moss Funaria hygrometrica under nutritional starvation.

Among the downstream targets of calcium in plants, calcium-dependent protein kinases (CDPKs) form an interesting class of kinases which are activated by calcium binding. They have been implicated in a diverse array of responses to hormonal and environmental stimuli. In order to dissect the role of CDPKs in the moss Funaria hygrometrica, a polymerase chain reaction (PCR)-based approach was adopted to clone the gene. Using degenerate PCR primers against conserved regions of CDPKs, a 900 bp amplicon was obtained from the genomic DNA of Funaria. Southern hybridization under low stringency conditions indicated the presence of several CDPK related sequences in the Funaria genome. This observation is consistent with reports of multigene families of CDPKs in other plants. The 900 bp fragment was subsequently used to isolate a 2.2 kb partial genomic clone of the CDPK gene from Funaria. The genomic clone encodes an open reading frame (ORF) of 518 amino acids. Interestingly, unlike other CDPK genes from plants, the entire 1.5 kb ORF is not interrupted by introns. The deduced amino acid sequence of the Funaria gene shows extensive homology with CDPKs from higher plants, 73% identity with the Fragaria CDPK and 71% identity with CDPK isoform 7 of Arabidopsis. Phylogenetic analysis revealed that the Funaria CDPK is closer to the CDPKs from higher plants like strawberry and Arabidopsis as compared to those from lower plants such as the liverwort Marchantia, the green alga Chlamydomonas or another moss Tortula. Northern analysis shows enhanced expression of the CDPK transcript within 24-48 h of starvation for nitrogen, phosphorus or sulphur. So far the only other kinase which is known to be induced by nutrient starvation in plants is the wpk 4 which is a snf-1 related kinase (SnRKs). To our knowledge this is the first report that implicates a CDPK in the starvation response.