Biosynthesis and Turnover of Cell Wall Glycoproteins during the Vegetative Cell Cycle of Chlamydomonas reinhardii

Abstract Biosynthesis and turnover of the different cell wall components have been studied during the vegetative cell cycle of Chlamydomonas reinhardii by pulse-labelling with [3H]proline and [35S]methionine and by pulse-chase experiments. Two phases of biosynthesis of insoluble cell wall material could be distinguished: 1. de novo synthesis of the daughter cell walls during cytokinesis and 2. cell wall enlargement during cell growth. During the cell enlargement period, a turnover of the insoluble wall component was observed. The released fragments were found to be accumulated in the culture medium. The LiCl-soluble cell wall glycoproteins were found to be precursors of the insoluble cell wall layer. Biosynthesis of the LiCl-soluble cell wall glycoproteins was observed mainly during the time period between cytokinesis and the end of the following cell enlargement period. Labelling of all the cell wall components was found to be strongly reduced during the time period between the end of the growth phase and cytokinesis. During cytokinesis, labelling of the insoluble cell wall material preceded the incorporation of radioactive precursors into the LiCl-soluble wall fraction.

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Macromolecules released into the culture medium during the vegetative cell cycle of the unicellular green alga Chlamydomonas reinhardii

Biochemical Journal ◽

10.1042/bj2260259 ◽

1985 ◽

Vol 226 (1) ◽

pp. 259-268 ◽

Cited By ~ 15

Author(s):

J Voigt

Keyword(s):

Cell Cycle ◽

Cell Wall ◽

Cell Growth ◽

Mother Cell ◽

Culture Medium ◽

Cell Enlargement ◽

Chlamydomonas Reinhardii ◽

Time Period ◽

Protein Components ◽

Mother Cell Wall

The culture medium of growing Chlamydomonas reinhardii cells contains hydroxyproline-rich glycoproteins, which are mainly liberated during release of the zoospores from the mother-cell wall. Pulse-labelling studies with [3H]proline and [35S]methionine have been performed in order to detect the protein components released by synchronously growing cells at different stages of the cell cycle. When either [3H]proline or [35S]methionine were applied during the phase of cell growth, radioactive label appeared in the released macromolecules after a lag period of 40 min, whereas incorporation into the insoluble part of the cell wall was delayed only by 20 min. When applied at the end of the growth phase, e.g. 13 h after beginning of the illumination period, the radioactive amino acids were incorporated into the cell wall, but radioactive labelling of macromolecules released into the culture medium could not be detected before the zoospores were liberated from the mother-cell wall. Maximal incorporation of [3H]proline and [35S]methionine into the insoluble part of the cell wall was observed during cell division, but essentially no radioactively-labelled macromolecules were released into the culture medium during this time period. Analysis of the macromolecules, which were liberated during cell enlargement, by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis revealed distinct radioactive bands, which were differentially labelled with [3H]proline and [35S]methionine. Among the macromolecules released into the culture medium during cell growth, a component of an apparent Mr 35 000 was preferentially labelled with [3H]proline. This component was also detected after labelling with [35S]methionine, but components of an apparently higher Mr were more prominent after labelling with [35S]methionine. Macromolecules released during the cell-enlargement period of synchronously growing cultures in the presence of [3H]proline contained radioactively-labelled hydroxyproline in addition to proline. These results show that, during cell-wall growth, specific protein components are released into the culture medium and that at least one of these components contains large amounts of proline and hydroxyproline. At least some of these macromolecules seem to be constituents of the cell wall, because during pulse-chase experiments radioactively-labelled macromolecules appeared in the culture medium mainly during the time period when the specific radioactivity of the insoluble inner-cell-wall layer decreased.

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Zoospore formation in Cylindrocapsa

Canadian Journal of Botany ◽

10.1139/b75-054 ◽

1975 ◽

Vol 53 (5) ◽

pp. 439-451 ◽

Cited By ~ 7

Author(s):

Larry R. Hoffman ◽

Cecilia S. Hofmann

Keyword(s):

Cell Wall ◽

Vegetative Cell ◽

Parental Cell ◽

Wall Material ◽

Cell Wall Material ◽

Daughter Cells ◽

Filamentous Green Algae ◽

Zoospore Release ◽

Zoospore Formation ◽

Altered Cell

Quadriflagellate zoospores and conditions for their induction are described for an algal isolate tentatively identified as Cylindrocapsa geminella Wolle. Previous to this report, only biflagellate zoospores were known for Cylindrocapsa while quadriflagellate zoospores were thought to characterize the closely related Cylindrocapsopsis; this distinction is no longer valid. In our isolate, a vegetative cell may differentiate directly into a single zoospore or, more commonly, zoosporogenesis is preceded by division of a vegetative cell into two, four, or eight daughter cells, each of which becomes a zoospore. Variation in zoospore arrangement depends on the number and nature of the division sequences. Ultimately, zoospores are released from the more-or-less dissociated parental cell wall in one or more vesicles. Each primary vesicle contains one, two, four, or occasionally eight zoospores; zoospore release follows the gradual distention and dissolution of the enclosing vesicle. Light microscopic observations suggest that the zoospore-containing vesicles arise from altered cell wall material. Zoospore germlings and variations in the appearance of vegetative filaments are aiso described and attention is called to the nature of the cell wall, which is quite unlike that of most other filamentous green algae.

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Ultrastructural investigations of enzyme treated cell wall material from industrial by-products.

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v40i2.16520 ◽

1992 ◽

Vol 40 (2) ◽

pp. 137-146

Author(s):

F.M. Engels ◽

N.A. Schalk

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Enzymic Activity ◽

Wall Material ◽

Cell Wall Material ◽

Plant Materials ◽

Carbohydrate Hydrolysis ◽

Cell Layers ◽

By Products ◽

Wall Components

Ultrastructural investigations of glycanase treatments of cell wall material from industrial by-products was carried out with the enzyme-thiocarbohydrazide-silver protein technique (ETAg). Driselase, gamanase and an experimental enzyme preparation with a broad spectra of hemicellulase, cellulase and pectolytic activities were used. Carbohydrate hydrolysis was found in cell walls and cell contents in 1-2 cell layers at the surface of 0.2-mm plant particles. Enzyme activity was detected to some extent inside unlignified and lignified cell walls. The absence of any reaction in some sublayers of the cell wall was indicative for the absence of polysaccharide substrate or a very tied interaction of cell wall components preventing enzymic activity or the absence of typical enzymes in crude preparations. It was concluded that the ETAg-technique can be useful to provide information about structural limitations of poorly degradable plant materials. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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The mechanism of surface growth in parenchyma of Avena coleoptiles

Australian Journal of Botany ◽

10.1071/bt9550137 ◽

1955 ◽

Vol 3 (2) ◽

pp. 137 ◽

Cited By ~ 35

Author(s):

AB Wardrop

Keyword(s):

Cell Wall ◽

Tip Growth ◽

Cell Types ◽

Cellulose Microfibrils ◽

Wall Material ◽

Cell Wall Material ◽

Cell Enlargement ◽

Electron Microscopic ◽

Stages Of Growth ◽

Preferred Direction

A study has been made of the organization of the cell wall in the parenchyma of Avena coleoptiles at successive stages of growth, using light and electron microscopic methods. It has been observed that extension of the parenchyma involves a progressive separation of the primary pit fields accompanied by an increasing dispersion of the cellulose microfibrils about their preferred direction of orientation. On the basis of this, and ancillary evidence from other cell types, it is suggested that extension growth involves stretching of the cell with the intercalation of new microfibrils into the expanding cell wall framework from the regions of the primary pit fields and penetration of the cell wall by plasmodesmata. It is considered that the evidence is consistent equally with the view either that the cell wall is stretched as water absorption accompanying enlargement takes place, or that cell enlargement is controlled by the synthesis of cell wall material at synthetic centres (pit fields and plasmodesmata) distributed over the cell surface. The concept of bipolar tip growth for coleoptile parenchyma is rejected.

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Napropamide Binding in Corn (Zea mays) Root Tissue

Weed Science ◽

10.1017/s0043174500070235 ◽

1983 ◽

Vol 31 (5) ◽

pp. 712-719 ◽

Cited By ~ 2

Author(s):

Michael Barrett ◽

Floyd M. Ashton

Keyword(s):

Cell Wall ◽

Zea Mays ◽

Cell Walls ◽

Wall Material ◽

Cell Wall Material ◽

Protease Treatment ◽

Wall Components ◽

Soluble Components ◽

Soluble Fractions

Napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide]-binding in excised root segments of corn (Zea maysL. ‘NC + 59′) was confined to cell wall fractions (residue and 500gpellet) remaining after homogenization and to components of the 100 000gsupernatant. Binding increased in both the cell wall and soluble fractions with continued exposure to napropamide. Microautoradiographs revealed that the napropamide bound in the cell walls was located in epidermal, cortical, and stelar tissue. Various proteins were capable of binding napropamide in vitro; however, protease treatment did not liberate the radioactivity bound in the cell wall fragments. Carbohydrate release from the cell wall material with cellulase was not correlated with the solubilization of bound radioactivity and wall carbohydrate monomers did not appear to bind to napropamide in vitro. A portion of the radioactivity found in the soluble components (at 100 000g) was associated with a molecule of MW > 600. The continued influx of napropamide was due to binding to cell wall components and molecules within the cell.

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Biosynthesis and release of cell wall-like glycoproteins during the vegetative cell cycle of Chlamydomonas reinhardii

Planta ◽

10.1007/bf00390026 ◽

1976 ◽

Vol 129 (2) ◽

pp. 183-189 ◽

Cited By ~ 19

Author(s):

Winfried C. Lang ◽

Maarten J. Chrispeels

Keyword(s):

Cell Cycle ◽

Cell Wall ◽

Vegetative Cell ◽

Chlamydomonas Reinhardii

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Synchrotron infrared microspectroscopy reveals the response of Sphagnum cell wall material to its aqueous chemical environment

Environmental Chemistry ◽

10.1071/en18120 ◽

2018 ◽

Vol 15 (8) ◽

pp. 513

Author(s):

Ewen Silvester ◽

Annaleise R. Klein ◽

Kerry L. Whitworth ◽

Ljiljana Puskar ◽

Mark J. Tobin

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Chemical Environment ◽

Wall Material ◽

Organic Soils ◽

Cell Wall Material ◽

Acid Base ◽

Widespread Species ◽

Flowing Liquid ◽

Infrared Microspectroscopy

Environmental contextSphagnum moss is a widespread species in peatlands globally and responsible for a large fraction of carbon storage in these systems. We used synchrotron infrared microspectroscopy to characterise the acid-base properties of Sphagnum moss and the conditions under which calcium uptake can occur (essential for plant tissue integrity). The work allows a chemical model for Sphagnum distribution in the landscape to be proposed. AbstractSphagnum is one the major moss types responsible for the deposition of organic soils in peatland systems. The cell walls of this moss have a high proportion of carboxylated polysaccharides (polygalacturonic acids), which act as ion exchangers and are likely to be important for the structural integrity of the cell walls. We used synchrotron light source infrared microspectroscopy to characterise the acid-base and calcium complexation properties of the cell walls of Sphagnum cristatum stems, using freshly sectioned tissue confined in a flowing liquid cell with both normal water and D2O media. The Fourier transform infrared spectra of acid and base forms are consistent with those expected for protonated and deprotonated aliphatic carboxylic acids (such as uronic acids). Spectral deconvolution shows that the dominant aliphatic carboxylic groups in this material behave as a monoprotic acid (pKa=4.97–6.04). The cell wall material shows a high affinity for calcium, with a binding constant (K) in the range 103.9–104.7 (1:1 complex). The chemical complexation model developed here allows for the prediction of the chemical environment (e.g. pH, ionic content) under which Ca2+ uptake can occur, and provides an improved understanding for the observed distribution of Sphagnum in the landscape.

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