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Green algae, Ulva Linnaeus, 1753 (Ulvales, Chlorophyta), is found abundantly in intertidal regions of the coasts. Members of the genus exist in foliose, filamentous, and tubular forms and may be distromatic or monostromatic. This study investigates the phylogenetic distribution of foliose Ulva from various geographical locations in India. The morphological and microscopic features of 20 specimens were studied, and ITS, tufA, 18S, and atpB regions were sequenced using specific primers. BLAST results were used for similarity search and MEGAX for phylogenetic reconstruction using these amplified sequences. A total of 35 sequences were generated and used to trace back the evolution of different species and the effects of geographical locations on the cryptic diversity of Ulva. Also, this study reports the occurrence of Ulva fasciata, Ulva reticulata, Ulva taeniata, Ulva linza, and Ulva ohnoi. A pressed herbarium voucher was prepared for future records of each sample. [ABSTRACT FROM AUTHOR]

Introduction: Studies have shown that the macroalga Ulva lactuca is the largest CO2 receptor. In Cuba, the possibility of installing a plant for its intensive cultivation is being evaluated, which contributes to mitigate CO2 and allows obtaining algal biomass in a sustainable way. For design calculations, equipment selection and operating conditions, it is necessary to know the maximum biomass yieldand its photosynthetic equation. Objective: To estimate quantitatively the CO2 fixation mechanism of the macroalga Ulva lactuca, using different alternatives of the photosynthesis equation based on the calculation of stoichiometric coefficients. Materials and Methods: To calculate the yield and the amounts of substrate and nutrients that the biomass is able to assimilate, mass balances are carried out to optimize the production of algal biomass, applying the method of stoichiometric coefficients in the photosynthesis reaction. Results and Discussion: The maximum cell yield of Ulva lactuca is 63.5 %. Of the photosynthesis equations proposed, alternative four has values closer to photosynthetic reality, since there is a great correspondence between the stoichiometry of microalgae growth and product formation, together with the availability of nitrogen and phosphorus sources. Both results allow us to deduce the production of microalgal biomass to implement an economically and environmentally profitable technology. Conclusions: The maximum biomass yield and the photosynthetic equation allow for design calculations, equipment selection and operating conditions to scale up the technological process. [ABSTRACT FROM AUTHOR]

Ulva is a green macroalgal genus with rich species diversity and worldwide distribution. While current knowledge on Ulva diversity focuses on temperate regions, genetic and morphological data in tropical and subtropical areas are scarce and the species richness is not clearly defined. The genus is known for its bloom-forming ability that can induce green tides leading to severe environmental and economic damage. In the last two decades, several important blooms of Ulva spp. have occurred in New Caledonia, requiring further investigations to identify the species involved. As knowledge of New Caledonian Ulva diversity is limited, an update to the Ulva spp. inventory in the area is essential. Based on Ulva specimens collected throughout New Caledonia (Grande Terre, Isle of Pines and Loyalty Islands), we (1) reassessed species diversity using species delimitation methods, (2) analysed morpho-anatomical characters to identify species and/or enrich their diagnosis, and (3) reconstructed a multilocus phylogeny (ITS, rbcL, tufA) of the genus. We found 21 secondary species hypotheses (SSHs) among our dataset, from which five were successfully assigned to U. lactuca, U. ohnoi, U. tepida, U. meridionalis and U. taeniata. Ten SSHs were defined as new species for which we provided taxonomic description, and six other SSHs were singletons that will need to be data-enriched for better interpretation. Our concatenated multilocus matrix included 61 Ulva species. Of these, 15 species were found in New Caledonia and were moderately to strongly supported. Among the Ulva species found in New Caledonia, seven are known to be bloom-forming which highlights the need for strict regulation and regular monitoring of water quality, particularly in areas exposed to strong nutrient input where these species can form green tides. Ulva diversity in New Caledonia was reassessed with 15 species highlighted. Ten new species have been discovered in New Caledonia. Indigenous species caused recent green tides in New Caledonia. [ABSTRACT FROM AUTHOR]

The green seaweed Ulva is important from ecological and economic perspectives, but the identification of species is often problematic. Here we assessed and discussed different perspectives to establish a stable taxonomic framework for Ulva, which will benefit both ecological and applied research. We evaluated (1) the performance of commonly used DNA-barcode markers (ITS rDNA, rbcL, and tufA) using species delimitation methods (PTP and GMYC), (2) the usage of species names in the literature, and (3) the geographic coverage of genetic data to identify poorly sampled regions. Species delimitation employing the tufA gene was the most consistent across methods. Not surprisingly, DNA-based species delimitation was often in disagreement with traditional morphology-based species definitions. Biological species concepts, where tested, proved to be generally narrower than DNA-based species delimitation. Although the use of molecular markers has greatly improved our view of Ulva diversity, the names associated with DNA sequences in public databases are often unreliable, complicating species identification. Recently, sequencing type materials has considerably reduced the gap between DNA sequence data and Linnaean names, but our knowledge on Ulva diversity remains inadequate, especially in tropical regions. Perspectives for Ulva taxonomy include the consistent use of multiple DNA-barcode markers assisted by species delimitation methods, applications of genomic data, and crossing experiments. To arrive at a stable nomenclature, we outline the benefits and shortcomings of adhering to the rules and practices of the International Code of Nomenclature for algae, fungi, and plants, for example, by sequencing name-bearing types and discuss alternative approaches. [ABSTRACT FROM AUTHOR]

Supralittoral and shallow water seaweed communities are particularly exposed to impacts such as climate change and disturbance by humans. Therefore, their classification, the study of composition, and the monitoring of their structural changes are particularly important. A phytosociological survey of the supralittoral and upper sublittoral vegetation of the South West Baltic Sea revealed eight phytobenthos communities with two variants comprising 35 taxa of macrophytes (18 taxa of Chlorophyta, 13 taxa of Rhodophyta and four taxa of Phaeophyceae, Ochrophyta). Five of the eight communities were dominated by Ulvales (Ulva intestinalis, Kornmannia leptoderma, and three Blidingia species), the other three by Fucus vesiculosus. Most Fucus vesiculosus-dominated communities contained U. intestinalis and U. linza as subdominants. Only one of the communities had until now been described as an association (Ulvetum intestinalis Feldman 1937). The syntaxonomic composition of the investigated vegetation includes both phytocenoses with the domination of green algae (Ulvetum intestinalis Feldman 1937 and communities of Blidingia marginata, unidentified Blidingia spp. and Kornmannia leptoderma), as well as a number of communities dominated by Fucus vesiculosus. Mainly boreal Atlantic species and cosmopolitans make up the bulk of the species in these associations. [ABSTRACT FROM AUTHOR]

Manawatāwhi/Three Kings Islands lie to the north of the North Island of New Zealand. Manawatāwhi is part of the rohe (territory) of Ngāti Kuri, with the islands having spiritual, cultural, political and customary significance. This group of small islands has one of the most pristine coastlines in New Zealand, with no human-mediated impacts from current land use, no permanent anchorage points, and landing on the islands is prohibited. The islands harbour a rich marine biota with a number of endemic species. A recent collection trip and molecular genetic studies using the rbcL marker revealed the presence of three entities of the genus Ulva L. (Ulvales, Chlorophyta) on the islands. One of these we describe herein as Ulva piritoka Ngāti Kuri, Heesch & W.A.Nelson, sp. nov. While it is genetically close to U. adhaerens Matsumoto & Shimada from Japan, differences in morphology, habitat and rbcL gene region, including the presence of a large group II intron in U. adhaerens, which was lacking in the Manawatāwhi specimen, led us to conclude U. piritoka sp. nov. belongs to a distinct species. We also confirmed the presence of Ulva compressa L. and Ulva rigida C.Agardh, both of which, although present on the New Zealand mainland, were originally described from Europe and are considered introductions to the New Zealand archipelago. These are the first reported marine non-indigenous species (NIS) recorded from Manawatāwhi/Three Kings Islands, and the implications of their presence are discussed. [ABSTRACT FROM AUTHOR]

Ulva is recognized as a cosmopolitan genus in the order Ulvales of Chlorophyta. Here, we describe a new species of free-living uniseriate Ulva from the eastern coast of the Indian subcontinent. Distinguishing morphological characteristics include unbranched compressed filamentous thalli, tufts of thallus attached via rhizoids, quadrilateral to elongated cells with round apices, and parietal chloroplasts with multiple pyrenoids per cell. Phylogenetic reconstruction using nrDNA ITS1 locus revealed a distinct monophyletic clade encompassing all of our uniseriate accessions, thus corroborating the new species proposition under the framework of phylogenetic species concept. The closest BLASTn hit was found to be Ulva prolifera, but our isolates had synapomorphic trait of compressed uniseriate thalli which is absent in Ulva prolifera or any of the previously described species of Ulva to date. Based on morphological and molecular synapomorphy, a new free-living uniseriate species Ulva uniseriata sp. nov. is formally proposed. [ABSTRACT FROM AUTHOR]

To better understand organelle genome evolution of the ulvophycean green alga Capsosiphon fulvescens, we sequenced and characterized its complete chloroplast genome. The circular chloroplast genome was 111,561 bp in length with 31.3% GC content that contained 108 genes including 77 protein‐coding genes, two copies of rRNA operons, and 27 tRNAs. In this analysis, we found the two types of isoform, called heteroplasmy, were likely caused by a flip‐flop organization. The flip‐flop mechanism may have caused structural variation and gene conversion in the chloroplast genome of C. fulvescens. In a phylogenetic analysis based on all available ulvophycean chloroplast genome data, including a new C. fulvescens genome, we found three major conflicting signals for C. fulvescens and its sister taxon Pseudoneochloris marina within 70 individual genes: (i) monophyly with Ulotrichales, (ii) monophyly with Ulvales, and (iii) monophyly with the clade of Ulotrichales and Ulvales. Although the 70‐gene concatenated phylogeny supported monophyly with Ulvales for both species, these complex phylogenetic signals of individual genes need further investigations using a data‐rich approach (i.e., organelle genome data) from broader taxon sampling. [ABSTRACT FROM AUTHOR]

The Kiel Canal is one of the world's most frequently used inland waterways and connects the SW Baltic Sea with the Wadden Sea. At the same time, the canal is a highly eutrophicated environment that is characterized by salinities that range from 3 to 16. This brackish character could make the Kiel Canal an important stepping stone for the introductions of species into the inner Baltic Sea. It could also hinder the identification of native and introduced species, given the fact that salinity sometimes severely affects algal morphology. Here we report on a survey of introduced and native seaweed species in the canal, focusing on the dominant groups, which are Fucales and Ulvales. Of the Fucales, the introduced species Fucus evanescens was detected nearly exclusively inside the canal, while Fucus vesiculosus dominated rockweed communities directly outside the sluice gates. Morphological analysis and genetic barcoding distinguished three species of Ulvales, Ulva linza, Ulva intestinalis and an unknown and possibly introduced species of the genus Blidingia. Species distributions and – in the case of U. intestinalis – branching patterns were clearly affected by salinity, while thallus sizes appeared to be affected by the specific eutrophication status of sites within the canal. [ABSTRACT FROM AUTHOR]

Combined genetic, morphological and ontogenetic observations show that the circumarctic boreal green algal macrophyte Kornmannia leptoderma has expanded its distribution range into the Baltic Sea, on a German coastal section of 220 km length. The species is also again (or still) established at its former extreme southern distribution limit in the North Sea, the German island of Helgoland, where it has not been detected during the last four decades. Macroscopic visible sporophytes of K. leptoderma are nowadays present in the Baltic Sea and at Helgoland from February to September, while they were in the past only detected from February to May at Helgoland. This capacity for formation of sporophytes in summer correlates with the circumstance that K. leptoderma from the Baltic Sea can complete its life cycle at 15°C while several studies conducted decades ago with material from Helgoland and from Pacific coasts consistently reported an inhibition of the algal gametogenesis at temperatures that exceed 12°C. Possibly K. leptoderma has undergone adaptations that facilitate its spread into warmer environments, unless the Kornmannia present in the Baltic Sea and on Helgoland today represents a newly introduced cryptic species. [ABSTRACT FROM AUTHOR]

To resolve historical misinterpretations of species descriptions and to comprehend the morphological diversity together with the distribution of Ulva compressa Linnaeus in northern Germany, a morphological and molecular study was undertaken of recently collected specimens and herbarium vouchers. Phylogenetic analyses from sequences of the plastid encoded tufA gene confirmed that U. compressa is abundant along the German Baltic Sea and North Sea coasts. We were able to genetically confirm the presence of U. compressa in the Baltic Sea below salinities of 15 PSU. However, we detected morphologies agreeing with the attached and branched tubular type material only in the North Sea, while U. compressa on Baltic Sea coasts indiscriminately exhibited a very distinct morphology of sheet-like thalli that were always unattached, with the exception of one collection site. Drifting forms were also frequently detected in the Wadden Sea, but not on the island of Helgoland. The tufA sequences of attached and tubular forms of U. compressa from the German Wadden Sea were identical to the drifting sheets found in the Wadden and Baltic Seas and the sequence divergence was extremely small at ≤0.9%. The proliferating, blade-like thalli of U. compressa appear as a nuisance ecotype that is able to form massive accumulations associated with oxygen depletion. Mass accumulations were observed to cause severe damage and increased mortality of habitat forming Zostera and Ruppia populations. [ABSTRACT FROM AUTHOR]

The paper presents four new sites where bright green Ulva thalli were found inhabiting freshwater (a river, a ditch, the Milet Canal) and marine (on the rocky shore of the Adriatic Sea) habitats in Montenegro. The aims of this study were to determine, for the first time, whether specimens of Ulva pilifera collected in Montenegro are phylogenetically and morphologically the same species as the one occurring in Europe. Using total reflection X-ray fluorescence (TXRF) and wavelength dispersive X-ray fluorescence (WDXRF) techniques it assessed the elemental composition of their thalli and its influence to colonise new habitats. Elements: Al, As, Ba, Br, Ca, Cl, Cr, Cu, Fe, Hf, I, K, Mg, Mn, Na, Ni, P, Pb, Rb, S, Si, Sr, Ti, V, and Zn were determined. The highest elemental concentrations were found for Ca = 16.3% (using WDXRF) and for Sr = 292 ppm (using TXRF) in the Ulva thalli. Ulva pilifera analysed from Montenegro, based on classical morphological methods and molecular techniques, are closely related to the same species from inland and coastal waters throughout Europe. The analysis of trace elements showed that the metal content in Ulva thalli is correlated with the trace elements in water and sediments. Ulva pilifera fits numerous features that make it one of the bioindicators of marine pollution, thanks to its worldwide distribution and capacity to accumulate trace elements.

Ulva lactuca (Chlorophyceae) has biotechnologically-important sulfated-polysaccharides (Ul-SPs), but their potentials on thrombin generation (TG) are unknown. This study analyzed the structural and physical-chemical features of the Ul-SPs as modulators of TG. Proteolytic digestion yielded (13.13%) extract containing sulfate (20.43%) and total sugars (65.72%), besides ulvan consisting of rhamnose, xylose, glucose, glucuronic acid and α-/β-types glycosidic linkages as characterized by one-/two-dimensions nuclear magnetic resonance (NMR) experiments. Fractionation of the Ul-SPs by DEAE-cellulose chromatography yielded Ul-SP1 and Ul-SP2 (0.50 and 0.75 M NaCl, respectively) showing sulfation (15.72-18.04%) and total sugars (59.73-60.58%) consistent with the charge density pattern by combination of agarose/polyacrylamide gel eletrophoresis using sequential staining with toluidine blue and stains-all, although with slight differences in their sizes (40 and >100 kDa, respectively). By both activated partial thromboplastin time (APTT) and prothrombin time (PT) tests, anticoagulation of the fractions was virtually detected by APTT (0.39 and 0.43 IU, respectively) against heparin (193 IU). Fractions acted differently on both intrinsic/extrinsic pathways in TG using 60-fold diluted human plasma, with 50% efficacies up to 8.3 µg, whereas at high concentrations suggested intrinsic hypercoagulability since heparin abolished both systems at low amounts. Ul-SPs block TG, but predicting thrombosis in increasing doses.

Some definitions of the term ‘lichen’ have often emphasized the role of the mycobiont as exhabitant in the symbiosis. Mastodia tessellata and Turgidosculum ulvae, both forming lichen-like associations with foliose algae, have traditionally defied that definition. In this study, we delve into the poorly known association of T. ulvae with Blidingia minima. Using four molecular markers (nrLSU, nrSSU, RPB1, mtSSU) we show that T. ulvae is a member of the family Verrucariaceae, closely related to the marine species Verrucaria ditmarsica. The presence of bitunicate asci and single-cell ascospores is confirmed. Our analysis of a fragment of the rbcL marker demonstrates that the photosynthetic partner belongs to B. minima, although relationships within this taxon remain unclear. Transmission electron microscopy allowed us to illustrate how T. ulvae interacts with Blidingia cells, and how haustoria in that species differ from those previously investigated in other marine lichen-forming fungi. [ABSTRACT FROM AUTHOR]

Large-scale green tides have been invading the coastal zones of the western Yellow Sea annually since 2008. Meanwhile, oceans are becoming more acid due to continuous absorption of anthropogenic carbon dioxide and intensive seaweed cultivation in Chinese coastal areas is leading to severe regional nutrient limitation. However, little is known the combined effects of global and local stressors on the eco-physiology of bloom-forming algae. We cultured Ulva linza under two levels of pCO2 (400 and 1000 μatm) and four treatments of nutrient (nutrient repletion, N limitation, P limitation, and N & P limitation) to investigate the physiological responses of this green tide alga to the combination of ocean acidification and nutrient limitation. For both sporelings and adult plants, elevated pCO2 did not affect the growth rate when cultured under nutrient replete conditions but reduced it under P limitation; N or P limitation by themselves reduced growth rate. P limitation resulted in a larger inhibition in growth for sporelings compared to adult plants. Sporelings under P limitation did not reach the mature stage after 16 days of culture while those under P repletion became mature by day 11. Elevated pCO2 reduced net photosynthetic rate for all nutrient treatments but increased nitrate reductase activity and soluble protein content under P replete conditions. N or P limitation reduced nitrate reductase activity and soluble protein content. These findings indicate that ocean acidification and nutrient limitation would synergistically reduce the growth of Ulva species and may thus hinder the occurrence of green tides in a future ocean environment [ABSTRACT FROM AUTHOR]

In ocean ecosystems, fluctuations in seawater pH affect CO2fluxes, fundamentally influencing the metabolism of marine algae, especially during the early stages of macroalgal development. In this study, short-term exposure tests (minutes) and prolonged culture experiments (eight days) were performed at different pH levels to investigate the growth and photosynthetic responses ofUlva lactuca(Ulvales, Chlorophyta) germlings. Both acidified and alkalized seawater significantly depressed algal photosynthesis during short-term exposure tests. Prolonged culture in acidified or alkalized seawater also notably decreased photosynthesis rates and growth rates ofU. lactucagermlings, but increased energy consumption and lipid peroxidation, indicating damage to the germlings. Our results suggested that both lowered and increased pH levels of seawater exert significant physiological stress onU. lactucagermlings. [ABSTRACT FROM AUTHOR]

In vitro cultivation of Gut Weed, Ulva intestinalis Linnaeus, was experimentally studied to support its near optimalfarming, with potential impact in Thailand on its direct use as human food or its co-cultures in shrimp farming.Germling clusters (2 weeks old and 7.50±2.98 mm long) were seeded into 500 mL flasks and biomass growth rateoptimized with respect to the main controllable factors; seedling density, salinity, light intensity, and temperature. These factorswere assumed to each have an optimal value independent of the others, and the factors were optimized one at a time. Themaximum growth at three to four weeks of cultivation was obtained at the factor levels of 0.05 gL-1, 20 ppt, 80 mol photonm-2s-1 and 25°C. Early zoosporangia were obtained from 2nd to 4th weeks. The relative growth rate ranged from 9.47 to 22.18 %day-1, and only asexual reproduction of U. intestinalis was observed under these culture conditions.

Species level identifications of morphologically simple marine algae have undoubtedly caused biodiversity assessments to be an arduous task. The green algal genus Ulva L., 1753, is notorious for morphological plasticity and cryptic speciation. We used two chloroplast-encoded (rbcL and tufA) molecular markers and the nuclear internal transcribed spacer 1 (ITS1) of the ribosomal cistron to detect Ulva ohnoi M. Hiraoka and S. Shimada, 2004, a species known for forming green tides in Japan, as a new record for the Western Atlantic, including the Gulf of Mexico (GoMX) and Atlantic coast of Florida. All rbcL sequences from this investigation were identical to reports for U. ohnoi. The Western Atlantic isolates showed relatively low genetic diversity in tufA and ITS1 sequences, which suggests that this species is not native to the GoMX and Atlantic Florida. Furthermore, we have identified U. ohnoi as the species that formed an ephemeral, localized overgrowth during July of 2013 in Biscayne Bay, Florida, an area with a persistent bloom of two other green algal species, Anadyomene stellata J. V. Lamouroux, 1812, and Anadyomene sp., due to eutrophication from anthropogenic nutrient loading near canals. A tissue nutrient analysis of samples from this overgrowth of Ulva showed that this species has a high affinity for nitrogen, especially ?15N, which suggests anthropogenic sources of N. Further investigations are needed to assess the geographical ranges of this species in this region as well as the potential invasiveness of this alga in the Western Atlantic. It is highly recommended to monitor the abundance of this species in response to nutrient discharges in Biscayne Bay. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD) of Ulva biomass, a promising next-generation feedstock for energy production, was investigated in sequencing batch mode. Over five cycles of operation, the methane yield decreased more than twofold (from 0.15 to 0.07 L/g COD fed ), while the organic treatment efficiency (i.e., chemical oxygen demand (COD) removal) remained fairly constant (53.7–61.1%). Such changes in reactor performance were related with structural variations in the microbial community, particularly the bacterial community, with repeated cycles. Methanosaeta - and Methanolinea -related populations were most likely the main aceticlastic and hydrogenotrophic methanogens, respectively, in the reactor. The emergence and prevalence of sulfate-reducing bacteria (SRBs), primarily a Solitalea -related population, most likely resulted in increased consumption of organic substrates for sulfate reduction, rather than methane production, in later cycles. Our observations suggest that the metabolic properties of the reactor changed with the transition of the bacterial community structure over cycles, and the metabolic shift had a negative effect on methanogenesis. The sequencing batch operation strategy applied in this study was not suitable for maximizing methane production from Ulva biomass, although the treatment efficiency was fairly stable. Robust control of SRB activity is necessary for more stable and efficient biomethanation of Ulva biomass in sequencing batch mode. [ABSTRACT FROM AUTHOR]

Ulvan is the main polysaccharide component of the Ulvales (green seaweed) cell wall. It is composed of disaccharide building blocks comprising 3-sulfatedrhamnoselinked toD-glucuronic acid (GlcUA), L-iduronic acid (IdoUA), or D-xylose (Xyl). The degradation of ulvan requires ulvan lyase, which catalyzes the endolytic cleavage of the glycoside bond between 3-sulfated rhamnose and uronic acid according to a β-elimination mechanism. The first characterized ulvan lyase was identified in Nonlabens ulvanivorans, an ulvanolytic bacterial isolate. In the current study,wehave identified and biochemically characterized novel ulvan lyases from three Alteromonadales isolated bacteria. Two homologous ulvan lyases (long and short) were found in each of the bacterial genomes. The protein sequences have no homology to the previously reported ulvan lyases and therefore are the first representatives of a new family of polysaccharide lyases. The enzymes were heterologously expressed in Escherichia coli to determine their mode of action. The heterologous expressed enzymes were secreted into the milieu subsequent to their signal sequence cleavage. An endolytic mode of action was observed and studied using gel permeation chromatography and 1HNMR.In contrast to N. ulvanivorans ulvan lyase, cleavage occurred specifically at the GlcUAresidues. In light of thegenomiccontextandmodularstructure of the ulvan lyase families identified to date, we propose that two ulvan degradation pathways evolved independently. [ABSTRACT FROM AUTHOR]

Ulvalean algae (Chlorophyta) are most commonly described from intertidal and shallow subtidal marine environments worldwide, but are less well known from mesophotic environments. Their morphological simplicity and phenotypic plasticity make accurate species determinations difficult, even at the generic level. Here, we describe the mesophotic Ulvales species composition from 13 locations across 2,300 km of the Hawaiian Archipelago. Twenty-eight representative Ulvales specimens from 64 to 125 m depths were collected using technical diving, submersibles, and remotely operated vehicles. Morphological and molecular characters suggest that mesophotic Ulvales in Hawaiian waters form unique communities comprising four species within the genera Ulva and Umbraulva, each with discrete geographic and/or depth-related distributional patterns. Three genetically distinct taxa are supported by both plastid ( rbcL and tufA) and nuclear ( ITS1) markers, and are presented here as new species: Umbraulva kaloakulau, Ulva ohiohilulu, and Ulva iliohaha. We also propose a new Umbraulva species ( Umbraulva kuaweuweu), which is closely related to subtidal records from New Zealand and Australia, but not formally described. To our knowledge, these are the first marine species descriptions from Hawai'i resulting from the collaboration of traditional Hawaiian nomenclature specialists, cultural practitioners and scientists. The difficulty of finding reliable diagnostic morphological characters for these species reflects a common problem worldwide of achieving accurate identification of ulvalean taxa using solely morphological criteria. Mesophotic Ulvales appear to be distinct from shallow-water populations in Hawai'i, but their degree of similarity to mesophotic floras in other locations in the Pacific remains unknown. [ABSTRACT FROM AUTHOR]

Previously defined by molecular studies undertaken in Japan and Australia as Ulva sp. 3 and in Hawaii as Ulva OTU6, Ulva sapora sp. nov. is described using combined morphological, anatomical, reproductive and molecular studies on 46 specimens from five localities on the tropical and subtropical east Australian coast. Ulva sapora is characterised by its unique internal transcribed spacer sequence and the following combination of characters: the main axis of the unbranched or branched filiform thallus increasing in breadth from the basal to the upper thallus, cells in surface view unordered except for short rows in some areas of the thallus, cells containing a single chloroplast covering half to the whole outer cell wall and containing 2-10 pyrenoids and many starch granules and reproduction by biflagellate zoids exhibiting differing phototactic responses. The new species is the result of the first critical taxonomic appraisal of the species of Ulva of the poorly investigated tropical east Australian marine macroalgal flora. Ulva sapora was the most abundant filiform species of Ulva in the region, accounting for 32% of the specimens collected during the study. [ABSTRACT FROM AUTHOR]

Sequencing mitochondrial and chloroplast genomes has become an integral part in understanding the genomic machinery and the phylogenetic histories of green algae. Previously, only three chloroplast genomes (Oltmannsiellopsis viridis, Pseudendoclonium akinetum, and Bryopsis hypnoides) and two mitochondrial genomes (O. viridis and P. akinetum) from the class Ulvophyceae have been published. Here, we present the first chloroplast and mitochondrial genomes from the ecologically and economically important marine, green algal genus Ulva. The chloroplast genome of Ulva sp. was 99,983 bp in a circular-mapping molecule that lacked inverted repeats, and thus far, was the smallest ulvophycean plastid genome. This cpDNA was a highly compact, AT-rich genome that contained a total of 102 identified genes (71 protein-coding genes, 28 tRNA genes, and three ribosomal RNA genes). Additionally, five introns were annotated in four genes: atpA (1), petB (1), psbB (2), and rrl (1). The circular-mapping mitochondrial genome of Ulva sp. was 73,493 bp and follows the expanded pattern also seen in other ulvophyceans and trebouxiophyceans. The Ulva sp. mtDNA contained 29 protein-coding genes, 25 tRNA genes, and two rRNA genes for a total of 56 identifiable genes. Ten introns were annotated in this mtDNA: cox1 (4), atp1 (1), nad3 (1), nad5 (1), and rrs (3). Double-cut-and-join (DCJ) values showed that organellar genomes across Chlorophyta are highly rearranged, in contrast to the highly conserved organellar genomes of the red algae (Rhodophyta). A phylogenomic investigation of 51 plastid protein-coding genes showed that Ulvophyceae is not monophyletic, and also placed Oltmannsiellopsis (Oltmannsiellopsidales) and Tetraselmis (Chlorodendrophyceae) closely to Ulva (Ulvales) and Pseudendoclonium (Ulothrichales). [ABSTRACT FROM AUTHOR]

Green macroalgae, such as Ulvales, lose their typical morphology completely when grown under axenic conditions or in the absence of the appropriate microbiome. As a result, slow growing aberrant phenotypes or even callus-like morphotypes are observed in Ulvales. The cross-kingdom interactions between marine algae and microorganisms are hence not only restricted by the exchange of macronutrients, including vitamins and nutrients, but also by infochemicals such as bacterial morphogenetic compounds. The latter are a fundamental trait mediating the mutualism within the chemosphere where the organisms interact with each other via compounds in their surroundings. Approximately 60 years ago, pilot studies demonstrated that certain bacteria promote growth, whereas other bacteria induce morphogenesis; this is particularly true for the order of Ulvales. However, only slow progress was made towards the underlying mechanism due to the complexity of, for example, algal cultivation techniques, and the lack of standardized experiments in the laboratory. A breakthrough in this research was the discovery of the morphogenetic compound thallusin, which was isolated from an epiphytic bacterium and induces normal germination restoring the foliaceous morphotypes of Monostroma. Owing to the low concentration, the purification and structure elucidation of highly biologically active morphogenetic compounds are still challenging. Recently, it was found that only the combination of two specific bacteria from the Rhodobacteraceae and Flavobacteriaceae can completely recover the growth and morphogenesis of axenic Ulva mutabilis cultures forming a symbiotic tripartite community by chemical communication. This review combines literature detailing evidences of bacteria-induced morphogenesis in Ulvales. A set of standardized experimental approaches is further proposed for the preparation of axenic algal tissues, bacteria isolation, co-cultivation experiments, and the analysis of the chemosphere. [ABSTRACT FROM AUTHOR]

We present the 96 005 bp circular chloroplast genome (cpDNA) ofUlva fasciata. This cpDNA was ∼4000 bp smaller than the cpDNA ofUlvasp. UNA00071828; however, this cpDNA was AT rich (75.1%) similar toUlvasp. TheU. fasciatacpDNA was also similar in gene content (101 identified genes) compared toUlvasp., which included 71 protein-coding genes, 3 ribosomal RNAs (rRNAs) and 27 transfer RNAs (tRNAs). Only one tRNA,trnN(AUU), that was present inUlvasp. was absent inU. fasciata. Five introns were present in the following genes ofU. fasciata:petB (2),psbD (1),psaB (1) andrrl(1).Ulvasp. lacked introns inpsbD andpsaB, and introns present inatpA andpsbB inUlvasp. were absent in the homologous genes ofU. fasciata. A gene arrangement comparison of bothUlvaspecies showed that a ∼27 000 bp segment of DNA consisting of genespsbB totrnT(UGU) was inverted. Furthermore, a phylogenetic analysis of 1135 bp of therbcL gene confirmed that this cpDNA and the previously published mitochondrial genome from this sample were indeed fromU. fasciata. [ABSTRACT FROM PUBLISHER]

Eating macroalgae (seaweeds) is considered an unusual activity in Turkey, although macroalgae have been known and prized for their nutritional purposes for many years in the Orient. The present study examines the addition of macroalgae to Turkish daily diets. Most Turkish meals begin withmezze, which is literally “a pleasant taste” and is probably derived from the Arabic wordmezaq, which means “the taste, the savor of a thing.” The green macroalgaUlva rigidaAgardh 1824 (Chlorophyta) was used to develop alternative protein-rich Turkish mezzes, using otherwise traditional recipes. U. rigidawas reared in tanks. The yield ofU. rigidain an onshore tank system demonstrated the potential ofU. rigidato produce marine biomass. TheU. rigidas were used in macroalga-based mezzes. The macroalga substituted grape leaves, spinach, lamb’s lettuce, salicornia, or lettuce and resulted in higher protein content than those vegetables. The preparedUlvamezzes were tested in regard to taste, smell, color, texture, and general appearance and scored “pretty good” and “perfect.” The results suggest thatUlvacan be produced and utilized for protein rich mezzes in Turkey. [ABSTRACT FROM AUTHOR]

An unknown green alga (order Ulvales) was a dominant macroalga in the rocky littoral zone of Lake Garda (southeastern Alps). Morphological and phylogenetic analyses indicated the alga was in the genus Jaoa, considered endemic to China. The alga in Lake Garda had numerous rhizoids, a subspherical hollow thallus with irregularly lobate-saccate morphology, and 3 layers (an outer layer of small cells with distinct chloroplasts, 2 pseudoparenchymatous, large, round, and mainly hyaline cell layers). Most characteristics were in agreement with the description of Jaoa bullata, 1 of 2 species belonging to the genus Jaoa. Phylogenetic analysis based on 3 loci ( rbcL, nrDNA 18S, and ITS) placed the alga in a clade with a sample identified as Jaoa prasina from a Chinese population, but with a considerable sequence distance, a result suggesting it might be a separate species. The Lake Garda alga is a siphonaxanthin-type species that possesses only nonP lipids as structural components of chloroplast (monogalactosyl diacylglycerols, digalactosyl diacylglycerols, and sulfoquinovosyl diacylglycerols) and other cell membranes (diacylglyceryl- N,N,N-trimethylhomoserine lipids). The alga is easily detected with the naked eye, occupies a characteristic belt in the eulittoral zone, and can be found wherever hard substrata are available. Neither this species nor similar taxa are mentioned in historical (end of the 19th century) papers on benthic algae of Lake Garda, so the alga probably was introduced to the lake in relatively recent times. This alga belongs to a little-known genus, but is easily observed and was discovered in Italy's largest lake, a tourist resource of outstanding importance. It is a striking example of the degree to which lake benthic algae are understudied in many areas. [ABSTRACT FROM AUTHOR]