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the extracellular-matrix-retaining cyanobacterium nostoc verrucosum accumulates trehalose, but is sensitive to desiccation.the aquatic cyanobacterium nostoc verrucosum forms macroscopic colonies, which consist of both cellular filaments and massive extracellular matrix material. in this study, the physiological features of n. verrucosum were investigated and compared with those of the anhydrobiotic cyanobacterium nostoc commune. nostoc verrucosum cells were sensitive to desiccation, but tolerant of freeze-thawing treatment in terms of both cell viability and photosynthetic o(2) evolution. natural colonies of these c ...201121507024
engineering of a plasmid-free escherichia coli strain for improved in vivo biosynthesis of astaxanthin.abstract: background: the xanthophyll astaxanthin is a high-value compound with applications in the nutraceutical, cosmetic, food, and animal feed industries. besides chemical synthesis and extraction from naturally producing organisms like haematococcus pluvialis, heterologous biosynthesis in non-carotenogenic microorganisms like escherichia coli, is a promising alternative for sustainable production of natural astaxanthin. recent achievements in the metabolic engineering of e. coli strains hav ...201121521516
antiviral effect of edaphic cyanophytes on rabies and herpes-1 viruses.five cyanophyte species (amorphonostoc punctiforme, gloeocapsa turgidus, sphaeronostoc coeruleum, stratonostoc linckia f. spongiaeforme and synechococcus cedrorum) were isolated and identified from sandy egyptian soils. polysaccharides extracted from these species showed a pronounced antiviral activity against rabies and herpes-1 viruses represented by the absence of the characteristic cytopathic effects of these viruses. it was found that 100 μg polysaccharide/ml induced 100% inhibition of the ...201121555271
biotransformation and volatilization of arsenic by three photosynthetic cyanobacteria.arsenic (as) is a pervasive and ubiquitous environmental toxin that has created world-wide human health problems. however, there are few studies about how organisms detoxify arsenic. cyanobacteria are capable of both photolithotrophic growth in the light and heterotrophic growth in the dark and are ubiquitous in soils, aquatic systems and wetlands. in this study, we investigated arsenic biotransformation in three cyanobacterial species (microcystis sp. pcc7806, nostoc sp. pcc7120 and synechocyst ...201121562336
a comparative study on effective cell disruption methods for lipid extraction from microalgae.aims:  to compare effective cell disruption methods for lipid extraction from fresh water microalgae. method and results:  chlorella sp., nostoc sp., and tolypothrix sp. were isolated from fresh water ponds in and around gandhigram, dindigul district, tamilnadu, india and used for lipid extraction. different methods, including autoclaving, bead-beating, microwave, sonication and a 10% nacl solution treatments were tested to identify the most effective cell disruption method. the total lipids fro ...201121575021
exposure of phototrophs to 548 days in low earth orbit: microbial selection pressures in outer space and on early earth.an epilithic microbial community was launched into low earth orbit, and exposed to conditions in outer space for 548 days on the european space agency expose-e facility outside the international space station. the natural phototroph biofilm was augmented with akinetes of anabaena cylindrica and vegetative cells of nostoc commune and chroococcidiopsis. in space-exposed dark controls, two algae (chlorella and rosenvingiella spp.), a cyanobacterium (gloeocapsa sp.) and two bacteria associated with ...201121593797
modeling photosystem i with the alternative reaction center protein psab2 in the nitrogen fixing cyanobacterium nostoc punctiforme.five nitrogen fixing cyanobacterial strains have been found to contain psab2, an additional and divergent gene copy for the photosystem i reaction center protein psab. in all five species the divergent gene, psab2, is located separately from the normal psaab operon in the genome. the protein, psab2, was recently identified in heterocysts of nostoc punctiforme sp. strain pcc 73102. 15 conserved amino acid replacements were identified by a multiple sequence alignment of several psab2 and psab1 seq ...201121605545
antiprotozoal, antitubercular and cytotoxic potential of cyanobacterial (blue-green algal) extracts from ireland.cyanobacteria (= blue-green algae) are prolific producers of structurally distinct and biologically active metabolites. in the continuation of our search for new sources of anti-infective natural products, we have assessed the in vitro antiprotozoal (plasmodium falciparum, trypanosoma brucei rhodesiense, t. cruzi, leishmania donovani) and antitubercular (mycobacterium tuberculosis) potential of samples of two terrestrial cyanobacteria, nostoc commune (collected when desiccated and wet) and rivul ...201121615033
do lichens domesticate photobionts like farmers domesticate crops? evidence from a previously unrecognized lineage of filamentous cyanobacteria.phylogenetic diversity of lichen photobionts is low compared to that of fungal counterparts. most lichen fungi are thought to be associated with just four photobiont genera, among them the cyanobacteria nostoc and scytonema, two of the most important nitrogen fixers in humid ecosystems. although many nostoc photobionts have been identified using isolated cultures and sequences, the identity of scytonema photobionts has never been confirmed by culturing or sequencing. we investigated the phylogen ...200921628288
structure and development of nostoc strands in leiosporoceros dussii (anthocerotophyta): a novel symbiosis in land plants.the presence of nostoc in longitudinally oriented schizogenous canals is a feature that separates leiosporoceros from all other hornworts and represents a novel symbiotic arrangement in land plants. in surface view, nostoc canals are visible as elongated, dichotomously branched blue-green strands. all other hornworts develop numerous discrete globose colonies through continuous production of mucilage clefts as avenues for multiple invasions within a single thallus. to elucidate the anatomy and d ...200621642133
kinetic control of one-pot trans-splicing reactions by using a wild-type and designed split intein. 201121656885
transcript analysis of the extended hyp-operon in the cyanobacteria nostoc sp. strain pcc 7120 and nostoc punctiforme atcc 29133. 201121672234
within-genome evolution of repins: a new family of miniature mobile dna in bacteria.repetitive sequences are a conserved feature of many bacterial genomes. while first reported almost thirty years ago, and frequently exploited for genotyping purposes, little is known about their origin, maintenance, or processes affecting the dynamics of within-genome evolution. here, beginning with analysis of the diversity and abundance of short oligonucleotide sequences in the genome of pseudomonas fluorescens sbw25, we show that over-represented short sequences define three distinct groups ...201121698139
effects of carbaryl and 1-naphthol on soil population of cyanobacteria and microalgae and select cultures of diazotrophic cyanobacteria.carbaryl application to soil collected from a rice fallow field was relatively less toxic to viable estimates of cyanobacteria and microalgae under nonflooded conditions than under flooded conditions. application of 1-naphthol, the hydrolysis product of carbaryl, to soil under both the regimes increased the population of both cyanobacteria and microalgae. soil application of carbaryl and 1-naphthol in combination, up to 1.0-ákg-áha(-1), was nontoxic to the viable population. the toxicity exerted ...201121706293
directional rna deep sequencing sheds new light on the transcriptional response of anabaena sp. strain pcc 7120 to combined-nitrogen deprivation.cyanobacteria are potential sources of renewable chemicals and biofuels and serve as model organisms for bacterial photosynthesis, nitrogen fixation, and responses to environmental changes. anabaena (nostoc) sp. strain pcc 7120 (hereafter anabaena) is a multicellular filamentous cyanobacterium that can "fix" atmospheric nitrogen into ammonia when grown in the absence of a source of combined nitrogen. because the nitrogenase enzyme is oxygen sensitive, anabaena forms specialized cells called hete ...201121711558
diverse two-cysteine photocycles in phytochromes and cyanobacteriochromes.phytochromes are well-known as photoactive red- and near ir-absorbing chromoproteins with cysteine-linked linear tetrapyrrole (bilin) prosthetic groups. phytochrome photoswitching regulates adaptive responses to light in both photosynthetic and nonphotosynthetic organisms. exclusively found in cyanobacteria, the related cyanobacteriochrome (cbcr) sensors extend the photosensory range of the phytochrome superfamily to shorter wavelengths of visible light. blue/green light sensing by a well-studie ...201121712441
development of a novel dnae intein-based assay for quantitative analysis of g-protein-coupled receptor internalization.g-protein-coupled receptor (gpcr) internalization provides a g-protein-subtype-independent method for assaying agonist-stimulated activation of receptors. we have developed a novel assay that allows quantitative analysis of gpcr internalization based on the interaction between activated gpcrs and +¦-arrestin2 and on nostoc punctiforme dnae intein-mediated reconstitution of renilla luciferase fragments. this assay system was validated using four functionally divergent gpcrs treated with agonists ...201121726524
diversity analysis of type i ketosynthase in rhizosphere soil of cucumber.fusarium wilt [fusarium oxysporum (sch1.) f.sp. cucumerinum owen.] is a major soil-borne disease of cucumber worldwide, and can cause huge yield losses. biological control of fusarium wilt of cucumber has received considerable attention. many bacteria, particularly actinomycetes, are known to produce secondary metabolites synthesized by polyketide synthases (pkss) with a diverse range of biological activities. ketosynthase (ks) gene diversity was analyzed in samples which were collected from rhi ...201121780139
freshwater cyanobacterium microcystis aeruginosa (utex 2385) induced dna damage in vivo and in vitro.microcystins are a family of potent hepatotoxins and liver tumor promoters produced by several genera of cyanobacteria including microcystis, nodularia, anabena, nostoc, etc. they are chemically very stable and represent a public health threat when they occur in water used for human consumption. we investigated the dna damage effects of m. aeruginosa utex 2385 in mouse liver in vivo and also in mammalian cells in vitro. the dna damage effect is compared with purified toxin microcystin-lr (mclr) ...199821781844
growth and heavy metals removal efficiency of nostoc muscorum and anabaena subcylindrica in sewage and industrial wastewater effluents.the growth of nostoc muscorum and anabaena subcylindrica in sterilized sewage wastewater and n. muscorum in sterilized wastewater of el-soda company was higher than those grown in allen synthetic medium. whereas, the growth of a. subcylindrica in el-soda company sterilized wastewater and n. muscorum as well as a. subcylindrica grown in verta company sterilized wastewater was slightly lower than that grown in the standard synthetic medium. the contents of chlorophyll a, carotenoids and protein of ...200521783496
production and characterization of antimicrobial active substance from the cyanobacterium nostoc muscorum.in this investigation, the cyanobacterium nostoc muscorum exhibited antagonistic activity against gram-positive and gram-negative bacteria and filamentous fungi. the results indicated that the active substance produced maximally after 12 days of incubation in shaken culture at 35-¦c, at ph 8.0 in bg-11 medium. the increase in nitrate concentration of the medium led to an increase in the antimicrobial production. chloroform was the best solvent for extracting the active material. the antagonistic ...200621783637
differential physiological and biochemical responses of two cyanobacteria nostoc muscorum and phormidium foveolarum against oxyfluorfen and uv-b radiation.in the present study, degree of tolerance and tolerance strategies of two paddy field cyanobacteria viz. nostoc muscorum and phormidium foveolarum against oxyfluorfen (10 and 20µgml(-1)) and uv-b (7.2kjm(-2)d(-1)) stress were investigated. oxyfluorfen and uv-b decreased growth, photosynthesis, nutrient uptake, nitrate reductase, acid and alkaline phosphatase activities, which accompanied with the increase in the level of oxidative stress. however, growth was more affected in n. muscorum than p. ...201121798597
novel glycosylated mycosporine-like amino acids with radical scavenging activity from the cyanobacterium nostoc commune.mycosporine-like amino acids (maas) are uv absorbing pigments, and structurally distinct maas have been identified in taxonomically diverse organisms. two novel maas were purified from the cyanobacterium nostoc commune, and their chemical structures were characterized. an maa with an absorption maximum at 335nm was identified as a pentose-bound porphyra-334 derivative with a molecular mass of 478da. another identified maa had double absorption maxima at 312 and 340nm and a molecular mass of 1050 ...201121813286
cyanobacterial lactate oxidases serve as essential partners in n2 fixation and evolved into photorespiratory glycolate oxidases in plants.glycolate oxidase (gox) is an essential enzyme involved in photorespiratory metabolism in plants. in cyanobacteria and green algae, the corresponding reaction is catalyzed by glycolate dehydrogenases (glcd). the genomes of n(2)-fixing cyanobacteria, such as nostoc pcc 7120 and green algae, appear to harbor genes for both glcd and gox proteins. the gox-like proteins from nostoc (no-lox) and from chlamydomonas reinhardtii showed high l-lactate oxidase (lox) and low gox activities, whereas glycolat ...201121828292
molecular cloning of maltooligosyltrehalose trehalohydrolase gene from nostoc flagelliforme and trehalose-related response to stresses.a genomic dna fragment encoding a putative maltooligosyltrehalose trehalohydrolase (nfmth) for trehalose biosynthesis was cloned by the degenerate primer- pcr from cyanobacterium nostoc flagelliforme. the orf of nfmth is 1,848 bp in length and encodes 615 amino acid residues, constituting a 70 kda protein. the deduced amino acid sequence of nfmth contains 4 regions highly conserved for mths. by expression of nfmth in e. coli, the function of this protein was demonstrated, where the recombinant p ...201121876373
integrating photobiological hydrogen production with dye-metal bioremoval from simulated textile wastewater.the study reports production of hydrogen in photobioreactors with free (pbr(fr)) and immobilized (pbr(imm)) nostoc biomass at enhanced and sustained rates. before running the photobioreactors, effects of different immobilization matrices and cyanobacterial dose on hydrogen production were studied in batch mode. as hydrogen production in the pbrs declined spent biomass from the photobioreactors were collected and utilized further for column biosorption of highly toxic dyes (reactive red 198+cryst ...201121890340
An ATP-grasp ligase involved in the last biosynthetic step of the iminomycosporine shinorine in Nostoc punctiforme ATCC 29133.We investigated the genetic basis for mycosporine sunscreen biosynthesis by the cyanobacterium Nostoc punctiforme ATCC 29133. Heterologous expression in Escherichia coli of three contiguous N. punctiforme genes (NpR5600, NpR5599, and NpR5598, here named mysA, mysB, and mysC, respectively) led to the production of mycosporine-glycine, an oxomycosporine. Additional expression of gene NpF5597 (mysD) led to the conversion of mycosporine-glycine into iminomycosporines (preferentially shinorine but al ...201121890703
Fungal lectin of Peltigera canina induces chemotropism of compatible Nostoc cells by constriction-relaxation pulses of cyanobiont cytoskeleton.A glycosylated arginase acting as a fungal lectin from Peltigera canina is able to produce recruitment of cyanobiont Nostoc cells and their adhesion to the hyphal surface. This implies that the cyanobiont would develop organelles to motility towards the chemoattractant. However when visualized by transmission electron microscopy, Nostoc cells recently isolated from P. canina thallus do not reveal any motile, superficial organelles, although their surface was covered by small spindles and serrate ...201121897128
Antagonistic interactions between filamentous heterotrophs and the cyanobacterium Nostoc muscorum.ABSTRACT:201121914201
post-storage potential of nostoc linckia (cyanobacteria) immobilized in ca-alginate (synthetic seed) as biofertilizer inocula. 201121914973
nostophycin biosynthesis is directed by a hybrid polyketide synthase-nonribosomal peptide synthetase in the toxic cyanobacterium nostoc sp. strain 152.cyanobacteria are a rich source of natural products with interesting pharmaceutical properties. here, we report the identification, sequencing, annotation, and biochemical analysis of the nostophycin (npn) biosynthetic gene cluster. the npn gene cluster spans 45.1 kb and consists of three open reading frames encoding a polyketide synthase, a mixed polyketide nonribosomal peptide synthetase, and a nonribosomal peptide synthetase. the genetic architecture and catalytic domain organization of the p ...201121948844
Phosphorus limitation for the colony formation, growth and photosynthesis of an edible cyanobacterium, Nostoc sphaeroides.The percentage of spherical colonies from the trichomes of Nostoc sphaeroides reached 62-73% after 16 days with 50 and 250 µM P, but only10-15% at 0.5 and 5 µM P. During colony formation from microcolonies to macrocolonies, the growth rates were 95, 206 and 244% higher, respectively at 5, 50 and 250 µM P than that at 0.5 µM P. The light-saturated photosynthetic rate, maximum electron transport rate and light-limited photosynthetic efficiency at 0.5 µM P decreased, respectively, by 45, 51 and 32% ...201221972139
Convergent evolution of a symbiotic duet: The case of the lichen genus Polychidium (Peltigerales, Ascomycota).• Premise of the study: Thallus architecture has long been a powerful guide for classifying lichens and has often trumped photobiont association and ascomatal type, but the reliability of these characters to predict phylogenetic affinity has seldom been tested. The cyanolichen genus Polychidium unites species that have strikingly similar gross morphology but consort with different photobiont genera. If Polychidium were found to be monophyletic, photobiont switching among closely related species ...201121980162
cytochrome c6-like protein as a putative donor of electrons to photosystem i in the cyanobacterium nostoc sp. pcc 7119.most organisms performing oxygenic photosynthesis contain either cytochrome c(6) or plastocyanin, or both, to transfer electrons from cytochrome b(6)-f to photosystem i. even though plastocyanin has superseded cytochrome c(6) along evolution, plants contain a modified cytochrome c(6), the so called cytochrome c(6a), whose function still remains unknown. in this article, we describe a second cytochrome c(6) (the so called cytochrome c(6)-like protein), which is found in some cyanobacteria but is ...201121984388
evaluation and comparison of protein splicing by exogenous inteins with foreign exteins in escherichia coli.protein splicing catalyzed by inteins has enabled various biotechnological applications such as protein ligation. successful applications of inteins are often limited by splicing efficiency. here, we report the comparison of protein splicing between 20 different inteins from various organisms in identical contexts to identify robust inteins with foreign exteins. we found that rada intein from pyrococcus horikoshii and an engineered dnab intein from nostoc punctiforme demonstrated an equally effi ...201122001202
Global transcription profiles of the nitrogen stress response resulting in heterocyst or hormogonium development in Nostoc punctiforme.The filamentous cyanobacterium Nostoc punctiforme differentiates from vegetative cells into three distinct cell types, heterocysts, hormogonia, and akinetes, in response to different stimuli. Cultures growing with ammonium can be induced to form hormogonia or heterocysts upon removal of the combined nitrogen. A DNA microarray consisting of 94% of the open reading frames predicted from the 9.059-Mb N. punctiforme genome was used to generate a global transcription data set consisting of seven time ...201122001509
photophysical diversity of two novel cyanobacteriochromes with phycocyanobilin chromophores: photochemistry and dark reversion kinetics.cyanobacteriochromes are phytochrome homologues in cyanobacteria that act as sensory photoreceptors. we compare two cyanobacteriochromes, rgs (coded by slr1393) from synechocystis sp. pcc 6803 and aphc (coded by all2699) from nostoc sp. pcc 7120. both contain three gaf (cgmp phosphodiesterase, adenylyl cyclase and fhla protein) domains (gaf1, gaf2 and gaf3). the respective full-length, truncated and cysteine point-mutated genes were expressed in escherichia coli together with genes for chromopho ...201222008418
hupw protease specifically required for processing of the catalytic subunit of the uptake hydrogenase in the cyanobacterium nostoc sp. strain pcc 7120.the maturation process of [nife] hydrogenases includes a proteolytic cleavage of the large subunit. we constructed a mutant of nostoc strain pcc 7120 in which hupw, encoding a putative hydrogenase-specific protease, is inactivated. our results indicate that the protein product of hupw selectively cleaves the uptake hydrogenase in this cyanobacterium.201222020512
Antioxidative Activity and Chemical Constituents of Edible Terrestrial Alga Nostoc commune Vauch.The extract of terrestrial alga Nostoc commune Vauch. has high antioxidative activity. Our study on N. commune Vauch. resulted in the isolation of two ß-ionone derivatives, nostocionone and 3-oxo-ß-ionone, together with four indole alkaloids, scytonemin, reduced scytonemin, N-(p-coumaroyl)tryptamine, and N-acetyltryptamine. The structures of the isolated compounds were determined on the basis of 1D and 2D NMR and MS analyses. Among these isolates, nostocionone and reduced scytonemin demonstrated ...201122056440
molecular genetic and chemotaxonomic characterization of the terrestrial cyanobacterium nostoc commune and its neighboring species.the phylogeny of the terrestrial cyanobacterium nostoc commune and its neighboring nostoc species was studied using molecular genetic and chemotaxonomic approaches. at least eight genotypes of n. commune were characterized by the differences among 16s rrna gene sequences and the peth gene encoding ferredoxin-nadp(+) oxidoreductase and by random amplified polymorphic dna analysis. the genotypes of n. commune were distributed in japan without regional specificity. the nrtp gene encoding nrtp-type ...201122066798
evidence for a sodium-dependent proline and glycine-betaine uptake in the cyanobacterium nostoc muscorum.the cyanobacterium nostoc muscorum is able to utilized proline and glycine-betaine as a nitrogen source under unstressed growth conditions. this cyanobacterium when grow in modified chu no. 10 medium (without na+) unable to utilized proline and glycine-betaine as a nitrogen source. spontaneously occurring mutant clones defective in na+ transport (na+-r) were isolated and analyzed for proline and glycine-betaine utilization. the mutant phenotype showed normal heterocyst frequency and nitrogenase ...201122073544
oxygen-independent alkane formation by non-heme iron-dependent cyanobacterial aldehyde decarbonylase: investigation of kinetics and requirement for an external electron donor.cyanobacterial aldehyde decarbonylase (cad) is, structurally, a member of the di-iron carboxylate family of oxygenases. we previously reported that cad from prochlorococcus marinus catalyzes the unusual hydrolysis of aldehydes to produce alkanes and formate in a reaction that requires an external reducing system but does not require oxygen [das et al. (2011) angew. chem. 50, 7148-7152]. here we demonstrate that cads from divergent cyanobacterial classes, including the enzyme from n. puntiformes ...201122074177
E622, a miniature, virulence-associated mobile element.Miniature inverted terminal repeat elements (MITEs) are nonautonomous mobile elements that have a significant impact on bacterial evolution. Here we characterize E622, a 611-bp virulence-associated MITE from Pseudomonas syringae, which contains no coding region but has almost perfect 168-bp inverted repeats. Using an antibiotic coupling assay, we show that E622 is transposable and can mobilize an antibiotic resistance gene contained between its borders. Its predicted parent element, designated T ...201222081398
Phylogenetic, chemical and morphological diversity of cyanobacteria from Portuguese temperate estuaries.Cyanobacteria from estuarine habitats have been poorly studied regarding diversity and potential bioactive compounds production compared with their fresh and marine waters' congeners. In this work, 44 cyanobacteria isolates characterised from three Portuguese estuarine environments. Identification was performed based on diacritical morphological features of the isolates (e.g. cell shape, cell size, presence/absence of sheaths) and on 16S rRNA gene sequences phylogenetic analysis. Diversity of pr ...201222093261
colour evaluation of a phycobiliprotein-rich extract obtained from nostoc pcc9205 in acidic solutions and yogurt.background: phycobiliproteins are coloured proteins produced by cyanobacteria, which have several applications because of their colour properties. however, there is no available information about the colour stability of phycobiliproteins from nostoc sp. in food systems. the aim of this work was to study the colour stability of a purple-coloured phycobiliprotein-rich extract from the cyanobacterium nostoc pcc9205 in acidic solutions and yogurt. results: variations of ph for nostoc pcc9205 extract ...201122095681
Second-Chance Initiation Dynamics of the Cyanobacterial Photocycle in the NpR6012 GAF4 Domain of Nostoc Punctiforme.The primary ultrafast Z-to-E isomerization photodynamics of the phytochrome-related cyanobacteri-ochrome (CBCR) NpR6012g4 from N. punctiforme were studied by transient absorption pump-dump-probe spec-troscopy. A 2-ps dump pulse resonant with the stimulated emission band depleted 21 % of the excited-state popula-tion, while the initial photoproduct Lumi-R was depleted by only 11 %. We observe a red-shifted ground-state in-termediate (GSI) that we assign to a metastable state that failed to fully ...201122107125
solution nmr structure of asl3597 from nostoc sp. pcc7120, the first structure from protein domain family pf12095, reveals a novel fold. 201122113821
Tolerance of the widespread cyanobacterium Nostoc commune to extreme temperature variations (-269 to 105°C), pH and salt stress.Nostoc commune is a widespread colonial cyanobacterium living on bare soils that alternate between frost and thaw, drought and inundation and very low and high temperatures. We collected N. commune from alternating wet and dry limestone pavements in Sweden and tested its photosynthesis and respiration at 20°C after exposure to variations in temperature (-269 to 105°C), pH (2-10) and NaCl (0.02-50 g NaCl kg(-1)). We found that dry field samples and rewetted specimens tolerated exposure beyond th ...201122120705
homologues and bioengineered derivatives of ltnj vary in ability to form d-alanine in the lantibiotic lacticin 3147.ltnα and ltnβ are individual components of the two-peptide lantibiotic lacticin 3147 and are unusual in that, although ribosomally synthesized, they contain d-amino acids. these result from the dehydration of l-serine to dehydroalanine by ltnm and subsequent stereospecific hydrogenation to d-alanine by ltnj. homologues of ltnj are rare but have been identified in silico in staphylococcus aureus c55 (sacj), pediococcus pentosaceus fbb61 (penn), and nostoc punctiforme pcc73102 (npnj, previously ca ...201122123251
Split-intein mediated re-assembly of genetically encoded Ca(2+) indicators.While genetically encoded Ca(2+) indicators (GECIs) allow Ca(2+) imaging in model organisms, the gene expression is often under the control of a single promoter that may drive expression beyond, the cell types of interest. To enable more cell-type specific targeting, GECIs can be brought under the, control of the intersecting expression from two promoters. Here, we present the splitting and, reassembly of two representative GECIs (TN-XL and GCaMP2) mediated by the split intein from Nostoc, punct ...201122133610
femtosecond photodynamics of the red/green cyanobacteriochrome npr6012g4 from nostoc punctiforme. 1. forward dynamics.phytochromes are well-known red/far-red photosensory proteins that utilize the photoisomerization of a linear tetrapyrrole (bilin) chromophore to detect the ratio of red to far-red light. cyanobacteriochromes (cbcrs) are related photosensory proteins with a bilin-binding gaf domain, but much more diverse spectral sensitivity, with five recognized subfamilies of cbcrs described to date. the mechanisms that underlie this spectral diversity have not yet been fully elucidated. one of the main cbcr s ...201122148715
femtosecond photodynamics of the red/green cyanobacteriochrome npr6012g4 from nostoc punctiforme. 2. reverse dynamics.phytochromes are red/far-red photosensory proteins that utilize photoisomerization of a linear tetrapyrrole (bilin) chromophore to photoconvert reversibly between red- and far-red-absorbing forms (p(r) and p(fr), respectively). cyanobacteriochromes (cbcrs) are related photosensory proteins with more diverse spectral sensitivity. the mechanisms that underlie this spectral diversity have not yet been fully elucidated. one of the main cbcr subfamilies photoconverts between a red-absorbing 15z groun ...201122148731
Reconstruction of structural evolution in the trnL intron P6b loop of symbiotic Nostoc (Cyanobacteria).In this study we reconstruct the structural evolution of the hyper-variable P6b region of the group I trnLeu intron in a monophyletic group of lichen-symbiotic Nostoc strains and establish it as a useful marker in the phylogenetic analysis of these organisms. The studied cyanobacteria occur as photosynthetic and/or nitrogen-fixing symbionts in lichen species of the diverse Nephroma guild. Phylogenetic analyses and secondary structure reconstructions are used to improve the understanding of the r ...201122210193
comparative analysis of cyanobacteria in the rhizosphere and as endosymbionts of cycads in drought-effected soils.does the diversity of cyanobacteria in the cycad rhizosphere relate to the cyanobiont species found in the coralloid roots of these ancient plants? the aim of this study was to identify the diversity of soil cyanobacteria occurring in the immediate vicinity of 22 colonised coralloid roots belonging to members of the cycad genera: macrozamia, lepidozamia, bowenia and cycas. the majority of coralloid roots were sampled at depths greater than 10 cm below the soil surface. a total of 32 cyanobacteri ...201222224502
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