Ultrastructural and chemical changes in the cell wall of Haematococcus pluvialis (Volvocales, Chlorophyta) during aplanospore formation

Hagen, Christoph; Siegmund, Stefan; Braune, W.

doi:10.1017/s0967026202003669

Cited by 211 publications

(179 citation statements)

References 21 publications

Supporting

Mentioning

159

Contrasting

Unclassified

Order By: Relevance

“…Different fibrilar and occasionally looped processes of Gigantosphaeridium fibratum n. gen. et sp., bear similarities to extant marine microalgae Sphaeropsis (Pterospermataceae, Chlorophyta) and Piropsis (Craspedophyta) from the North Sea and Arctic Sea (AlgaeBASE). Secondary wall synthesis during the cyst stage was observed in several extant taxa: chlorophyte Haematococcus pluvialis (Hagen et al, 2002;Damiani et al, 2006) and charophyte M. thomasiana (Blackburn and Tyler, 1981), Volvocales (Hagen et al, 2002), resembling features in the studied taxa.…”

supporting

confidence: 52%

“…Ultrastructural studies on organic walls in Proterozoic and Cambrian microfossils (Arouri et al, 1999(Arouri et al, , 2000Talyzina and Moczydłowska, 2000;Kempe et al, 2002Kempe et al, , 2005Javaux et al, 2004;Willman and Moczydłowska, 2007;Moczydłowska and Willman, 2009;Schiffbauer and Xiao, 2009;Willman, 2009;Moczydłowska et al, 2010) reinforced this interpretation by identifying significant complexity and multilayering comparable to that in modern photosynthesizing protists and certain microalgal species. Phylogenetically diverse protistan clades are known to produce preservable cysts as a part of their life and reproduction cycle, regardless of whether they are asexual (i.e., prasinophyte resting cysts) or sexual (zygotic cysts in chlorophytes, charophytes, and dinoflagellates) (Evitt, 1985;Margulis et al, 1989;Dale, 2001;Hagen et al, 2002;Raven et al, 2005;Damiani et al, 2006;Head et al, 2006). Cyst wall resistance (preservability without permineralization) demonstrates specific requirements for successful reproduction: the protection of the maturing zygote (Graham and Wilcox, 2000; Agić et al-Mesoproterozoic algal microfossils, Shanxi, China Moczydłowska et al, 2011).…”

Section: Life Cyclementioning

confidence: 99%

See 1 more Smart Citation

Affinity, life cycle, and intracellular complexity of organic-walled microfossils from the Mesoproterozoic of Shanxi, China

Agić¹,

Moczydłowska²,

Yin

2015

J. Paleontol.

View full text Add to dashboard Cite

Abstract.-Light microscope and scanning electron microscope observations on new material of unicellular microfossils Dictyosphaera macroreticulata and Shuiyousphaeridium macroreticulatum, from the Mesoproterozoic Ruyang Group in China, provide insights into the microorganisms' biological affinity, life cycle and cellular complexity. Gigantosphaeridium fibratum n. gen. et sp., is described and is one of the largest Mesoproterozoic microfossils recorded. Phenotypic characters of vesicle ornamentation and excystment structures, properties of resistance and cell wall structure in Dictyosphaera and Shuiyousphaeridium are all diagnostic of microalgal cysts. The wide size ranges of the various morphotypes indicate growth phases compatible with the development of reproductive cysts. Conspecific biologically, each morphotype represents an asexual (resting cyst) or sexual (zygotic cyst) stage in the life cycle, respectively. We reconstruct this hypothetical life cycle and infer that the organism demonstrates a reproductive strategy of alternation of heteromorphic generations. Similarly in Gigantosphaeridium, a metabolically expensive vesicle with processes suggests its protective role as a zygotic cyst. In combination with all these characters and from the resemblance to extant green algae, we propose the placement of these ancient microorganisms in the stem group of Chloroplastida (Viridiplantae). A cell wall composed of primary and secondary layers in Dictyosphaera and Shuiyouisphaeridium required a high cellular complexity for their synthesis and the presence of an endomembrane system and the Golgi apparatus. The plastid was also present, accepting the organism was photosynthetic. The biota reveals a high degree of morphological and cell structural complexity, and provides an insight into ongoing eukaryotic evolution and the development of complex life cycles with sexual reproduction by 1200 Ma.

show abstract

supporting

confidence: 52%

Section: Life Cyclementioning

confidence: 99%

Affinity, life cycle, and intracellular complexity of organic-walled microfossils from the Mesoproterozoic of Shanxi, China

Agić¹,

Moczydłowska²,

Yin

2015

J. Paleontol.

View full text Add to dashboard Cite

show abstract

“…Based on scanning microscopy, pectic layers consist of a hexagonal network of electron-dense material on the surface, and a system of tubules radiating out from the middle layer. Haematococcus, a motile cell, has a wide distinct gelatinous multilayered extracellular matrix made up of interlocking fibers, granular and crystalline elements (Hagen et al, 2002). The tripartite crystalline layer interjects between inner layer composed of a loose net of fibrous-granular structures and the outer fibrous stratum.…”

Section: Cell Wall Types In Various Groups Of Microalgae and Cyanobacmentioning

confidence: 99%

Cell disruption technologies

Dhondt

Martín-Juárez

Bolado

et al. 2017

Microalgae-Based Biofuels and Bioproducts

View full text Add to dashboard Cite

IntroductionAlgal cell walls separate the inside cell content from the environment to protect the cell against desiccation, pathogens, and predators while still allowing exchange of compounds. Toward application of algae biomass as a sustainable resource, disruption of this cell wall (¼cell disruption) is an essential pretreatment step to maximize product recovery in downstream processes of the algae biorefinery. Also for direct use of algae in feed or food, cell rupture is required to increase the bioavailability of algae constituents. Depending on the cell wall structure, the size, and the shape of algae, cell disruption can be challenging. A variety of cell disruption methods is currently available, and new approaches are being elaborated in parallel. Since downstream processing is responsible for a large part of the operational costs in the whole production chain, cell disruption technologies should be low cost and energy efficient and result preferably in high product quality. This chapter provides information on cell wall types and gives an overview of physical-mechanical and (bio-)chemical cell disruption technologies with attention to development stage, energy efficiency, product quality, costs, emerging approaches, and applicability on large scale. Cell wall types in various groups of microalgae and cyanobacteriaThe cell wall composition and architecture of algae and cyanobacteria are highly variable ranging from tiny membranes to multilayered complex structures. Despite the importance of algal cell wall properties in biotechnology, little structural information is available for most species (Scholz et al., 2014). Based on the complexity of surface structures, four cell types could be distinguished (Barsanti and Gualtieri, 2006;Lee, 2008) (Fig. 6.1). A simple cell membrane (Fig. 6.1, Type 1) is present in short-lived stages (e.g., gametes), chrysophytes, raphidophytes, green algae Dunaliella, and haptophytes Isochrysis. It consists of a lipid bilayer with integrated and peripheral proteins. Sometimes a cap of glycolipids and glycoproteins envelops the outer surface of cell membrane. Cell membranes with additional extracellular material are known in cyanobacteria and many groups of algae, including palmelloid phases. It is the most diverse cell wall type that includes various membrane-associated structures (cell wall, Microalgae-Based Biofuels and Bioproducts. http://dx

show abstract

“…12D), and no subplasmalemmal cisternae are present. Hagen et al (39) provided an image of the smooth convex face of eisosomes in H. pluvialis cysts.…”

Section: Resultsmentioning

confidence: 99%

“…However, the term "eisosome" has entered the published literature and is used in this report to designate this class of membrane differentiation. Several published studies of unicellular green algae have included freeze fracture images of rod-like plasma membrane furrows that are morphologically homologous to fungal eisosomes (3,13,(37)(38)(39). During the course of a recent quickfreeze deep-etch electron microscopic (QFDEEM) (40) survey of several dozen unicellular algae deemed to be candidate producers of triacylglycerols for biodiesel, we obtained high-resolution images of eisosomes from members of several red and green microalgal radiations, including lichen photobionts.…”

mentioning

confidence: 99%

Eisosome Ultrastructure and Evolution in Fungi, Microalgae, and Lichens

et al. 2015

View full text Add to dashboard Cite

Eisosomes are among the few remaining eukaryotic cellular differentations that lack a defined function(s). These trough-shaped invaginations of the plasma membrane have largely been studied in Saccharomyces cerevisiae, in which their associated proteins, including two BAR domain proteins, have been identified, and homologues have been found throughout the fungal radiation. Using quick-freeze deep-etch electron microscopy to generate high-resolution replicas of membrane fracture faces without the use of chemical fixation, we report that eisosomes are also present in a subset of red and green microalgae as well as in the cysts of the ciliate Euplotes. Eisosome assembly is closely correlated with both the presence and the nature of cell walls. Microalgal eisosomes vary extensively in topology and internal organization. Unlike fungi, their convex fracture faces can carry lineagespecific arrays of intramembranous particles, and their concave fracture faces usually display fine striations, also seen in fungi, that are pitched at lineage-specific angles and, in some cases, adopt a broad-banded patterning. The conserved genes that encode fungal eisosome-associated proteins are not found in sequenced algal genomes, but we identified genes encoding two algal lineage-specific families of predicted BAR domain proteins, called Green-BAR and Red-BAR, that are candidate eisosome organizers. We propose a model for eisosome formation wherein (i) positively charged recognition patches first establish contact with target membrane regions and (ii) a (partial) unwinding of the coiled-coil conformation of the BAR domains then allows interactions between the hydrophobic faces of their amphipathic helices and the lipid phase of the inner membrane leaflet, generating the striated patterns.

show abstract

Ultrastructural and chemical changes in the cell wall of Haematococcus pluvialis (Volvocales, Chlorophyta) during aplanospore formation

Cited by 211 publications

References 21 publications

Affinity, life cycle, and intracellular complexity of organic-walled microfossils from the Mesoproterozoic of Shanxi, China

Affinity, life cycle, and intracellular complexity of organic-walled microfossils from the Mesoproterozoic of Shanxi, China

Cell disruption technologies

Eisosome Ultrastructure and Evolution in Fungi, Microalgae, and Lichens

Contact Info

Product

Resources

About