The organization of the primary wall in differentiating conifer tracheids

In a study of differentiating tracheids of Pinus radiata evidence has been obtained which suggests that, in those cells with localized apical growth, surface enlargement takes place by the multi-net mechanism of wall growth. Features described, such as the difference in microfibril orientation on the inner and outer surfaces of the cell wall and the existence of well-developed corner thickenings, closely resemble similar features in elongating coleoptile parenchyma. It is argued that growth is not limited to the extreme tips of the cells as in root hairs, but that the growth zone extends some distance back from the cell ends.

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Cell wall biosynthesis and the molecular mechanism of plant enlargement

Functional Plant Biology ◽

10.1071/fp09048 ◽

2009 ◽

Vol 36 (5) ◽

pp. 383 ◽

Cited By ~ 67

Author(s):

John S. Boyer

Keyword(s):

Cell Wall ◽

Critical Level ◽

Turgor Pressure ◽

Chara Corallina ◽

Wall Material ◽

Primary Wall ◽

Terrestrial Plants ◽

Green Plants ◽

Wall Deposition ◽

Wall Growth

Recently discovered reactions allow the green alga Chara corallina (Klien ex. Willd., em. R.D.W.) to grow well without the benefit of xyloglucan or rhamnogalactan II in its cell wall. Growth rates are controlled by polygalacturonic acid (pectate) bound with calcium in the primary wall, and the reactions remove calcium from these bonds when new pectate is supplied. The removal appears to occur preferentially in bonds distorted by wall tension produced by the turgor pressure (P). The loss of calcium accelerates irreversible wall extension if P is above a critical level. The new pectate (now calcium pectate) then binds to the wall and decelerates wall extension, depositing new wall material on and within the old wall. Together, these reactions create a non-enzymatic but stoichiometric link between wall growth and wall deposition. In green plants, pectate is one of the most conserved components of the primary wall, and it is therefore proposed that the acceleration-deceleration-wall deposition reactions are of wide occurrence likely to underlie growth in virtually all green plants. C. corallina is one of the closest relatives of the progenitors of terrestrial plants, and this review focuses on the pectate reactions and how they may fit existing theories of plant growth.

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AUTORADIOGRAPHIC STUDIES OF BACTERIAL CELL WALL REPLICATION: I. CELL WALL GROWTH OF BACILLUS CEREUS IN THE PRESENCE OF CHLORAMPHENICOL

Canadian Journal of Microbiology ◽

10.1139/m67-046 ◽

1967 ◽

Vol 13 (4) ◽

pp. 341-350 ◽

Cited By ~ 7

Author(s):

K. L. Chung

Keyword(s):

Cell Wall ◽

Cell Division ◽

Bacillus Cereus ◽

First Generation ◽

Third Generation ◽

Cell Wall Synthesis ◽

Daughter Cells ◽

Entire Cell ◽

Wall Growth ◽

The Difference

The pattern of cell wall synthesis as measured by the incorporation of tritiated alanine into the cell wall of Bacillus cereus, and the number of synthesizing sites in the cell wall were studied by the direct and the reverse autoradiographic labelling methods.In the absence of chloramphenicol, the new cell wall was initiated at two or three segments, and later increased to four or five segments which continued to elongate but not to increase in number until the bacilli had made preparation for cell division. Shortly before the centripetal growth of the cell wall and constriction to separate daughter cells, two to three more new wall-segments were added to those already present. The second and third generation cells retained some old wall-segments from the first-generation mother, which remained as discrete clusters of grains, and could easily be distinguished from the new segments.In the presence of chloramphenicol, the new wall was initiated at 8 to 10 sites. Further incubation resulted in the uniform incorporation of labels at multiple sites along the entire cell length.The patterns of new wall replication as studied by the two methods were compared. To account for the difference in synthesizing sites when chloramphenicol is present, it is suggested that the cells have either used the maximum number of sites or have completely bypassed all the sites and allowed the tritiated alanine to diffuse into the wall to become incorporated.

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Transcriptome profiling of Pinus radiata juvenile wood with contrasting stiffness identifies putative candidate genes involved in microfibril orientation and cell wall mechanics

BMC Genomics ◽

10.1186/1471-2164-12-480 ◽

2011 ◽

Vol 12 (1) ◽

Cited By ~ 25

Author(s):

Xinguo Li ◽

Harry X Wu ◽

Simon G Southerton

Keyword(s):

Cell Wall ◽

Candidate Genes ◽

Pinus Radiata ◽

Juvenile Wood ◽

Transcriptome Profiling ◽

Microfibril Orientation ◽

Cell Wall Mechanics

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Helicoidal microfibril deposition in a tip-growing cell and microtubule alignment during tip morphogenesis: a dry-cleaving and freeze-substitution study

Canadian Journal of Botany ◽

10.1139/b89-307 ◽

1989 ◽

Vol 67 (8) ◽

pp. 2401-2408 ◽

Cited By ~ 42

Author(s):

Anne Mie C. Emons

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Root Hair ◽

Root Hairs ◽

Freeze Substitution ◽

Axial Direction ◽

Microfibril Orientation ◽

Growing Cell ◽

Equisetum Hyemale ◽

Dry Cleaving

Cell wall microfibril alignment in the tubular portion of Equisetum hyemale root hairs is helicoidal. Lamellae of helicoidal texture are deposited from tip to base; thus, different microfibril orientations are aligned with the plasma membrane successively. Zones with constant mean microfibril orientation are about 300 μm long. In any such zone of dry-cleaned, shadowed preparations, the frequency of microfibrils at the proximal end is 5 to 7 microfibrils per micrometre, which decreases to 0 at the distal end. The orientation of microfibrils of the underlying lamella, the microfibril frequency of which is 5 to 7/μm throughout, is the same as the microfibril orientation of the neighbouring distal lamella. Microfibrils of the cell wall are randomly oriented in the hair dome. Microtubule alignment in these root hairs was examined by means of freeze substitution. In the extreme tip of the root hair, microtubules run parallel to the plasma membrane and transverse to the long axis of the hair; the hemisphere of the hair contains randomly oriented microtubules. From extreme tip to base of the hair dome, microtubules become more and more axially aligned, and remain axially oriented in the hair tube. Further down the hair, where microfibril alignment is transverse and microfibrils are actively being deposited, microtubules still run in the axial direction. The observations emphasize the involvement of microtubles in root hair tip morphogenesis, but not in determining the alignment of the microfibrils in the hair tube.

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Influence of Cell Wall Composition on the Fossilisation of Bacteria and the Implications for the Search for Early Life Forms

International Astronomical Union Colloquium ◽

10.1017/s0252921100015025 ◽

1997 ◽

Vol 161 ◽

pp. 491-504 ◽

Cited By ~ 3

Author(s):

Frances Westall

Keyword(s):

Cell Wall ◽

Life Forms ◽

Cation Binding ◽

Positive Bacterium ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Transmission Electron ◽

Hydrothermal Sediments ◽

Identification Of Bacteria ◽

The Difference

AbstractThe oldest cell-like structures on Earth are preserved in silicified lagoonal, shallow sea or hydrothermal sediments, such as some Archean formations in Western Australia and South Africa. Previous studies concentrated on the search for organic fossils in Archean rocks. Observations of silicified bacteria (as silica minerals) are scarce for both the Precambrian and the Phanerozoic, but reports of mineral bacteria finds, in general, are increasing. The problems associated with the identification of authentic fossil bacteria and, if possible, closer identification of bacteria type can, in part, be overcome by experimental fossilisation studies. These have shown that not all bacteria fossilise in the same way and, indeed, some seem to be very resistent to fossilisation. This paper deals with a transmission electron microscope investigation of the silicification of four species of bacteria commonly found in the environment. The Gram positiveBacillus laterosporusand its spore produced a robust, durable crust upon silicification, whereas the Gram negativePseudomonas fluorescens, Ps. vesicularis, andPs. acidovoranspresented delicately preserved walls. The greater amount of peptidoglycan, containing abundant metal cation binding sites, in the cell wall of the Gram positive bacterium, probably accounts for the difference in the mode of fossilisation. The Gram positive bacteria are, therefore, probably most likely to be preserved in the terrestrial and extraterrestrial rock record.

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SEM and fluorescence imaging of callose deposition in root hair tips and suspension cultures of Streptanthus tortuosus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161047 ◽

1990 ◽

Vol 48 (3) ◽

pp. 698-699

Author(s):

K.S. Walters ◽

R.D. Sjolund ◽

K.C. Moore

Keyword(s):

Cell Wall ◽

Root Hair ◽

Cultured Cells ◽

Root Hairs ◽

Callus Cultures ◽

Callose Deposition ◽

Culture Cells ◽

Wall Structures ◽

Ultraviolet Illumination ◽

Callose Formation

Callose, B-1,3-glucan, a component of cell walls, is associated with phloem sieve plates, plasmodesmata, and other cell wall structures that are formed in response to wounding or infection. Callose reacts with aniline blue to form a fluorescent complex that can be recognized in the light microscope with ultraviolet illumination. We have identified callose in cell wall protuberances that are formed spontaneously in suspension-cultured cells of S. tortuosus and in the tips of root hairs formed in sterile callus cultures of S. tortuosus. Callose deposits in root hairs are restricted to root hair tips which appear to be damaged or deformed, while normal root hair tips lack callose deposits. The callose deposits found in suspension culture cells are restricted to regions where unusual outgrowths or protuberances are formed on the cell surfaces, specifically regions that are the sites of new cell wall formation.Callose formation has been shown to be regulated by intracellular calcium levels.

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STRUKTUR DAN FISIOGNOMI VEGETASI MANGROVE DI REMPANG CATE KOTA BATAM

SIMBIOSA ◽

10.33373/sim-bio.v3i1.250 ◽

2014 ◽

Vol 3 (1) ◽

Author(s):

Yarsi Efendi ◽

Dahrul Aman Harahap

Keyword(s):

Data Collection ◽

Coastal Area ◽

Growth Zone ◽

Mangrove Area ◽

Rhizophora Apiculata ◽

The Difference ◽

Mangrove Zonation ◽

Vertical Transect ◽

Zone Growth ◽

Vegetation Physiognomy

Structure and physiognomy of mangrove strongly influenced by the zonation that occurred in the area of mangroves growth. The differences of zona growth will effect to differences in the structure and composition of vegetation. There are three zones in the mangrove area, which is caused by the difference of flooding which also resulted in the difference to the salinity. The differences of growth zone will performed to the type vegetation performance (Physiognomy). This study is aims to prove the mangrove’s physiognomy that taken in the coastal area of Rempang Cate Batam, on March 2014 to June 2014. This study was a survey with data collection using a vertical transect plots 100 m. Based on the research that has been done obtained difference vegetation physiognomy stands for every level of growth in each zone growth. Proximally found 13 species of mangroves in 8 families. The results of the analysis of the vegetation on the trees growth level are, Ceriops decandra have the greatest significance important value 167.55% on sapling (juvenille ) level is dominated by Rhizophora apiculata 120%, and seedling growth level dominated by Rhizophora apiculata 186.80%. Keywords: Structure and physiognomy, mangrove zonation

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Sector growth and symmetry of (F,OH) apatite from the Asio mine, Japan

Mineralogical Magazine ◽

10.1180/minmag.1994.058.391.13 ◽

1994 ◽

Vol 58 (391) ◽

pp. 307-314 ◽

Cited By ~ 2

Author(s):

Mizuhiko Akizuki ◽

Hirotugu Nisidoh ◽

Yasuhiro Kudoh ◽

Tomohiro Watanabe ◽

Kazuo Kurata

Keyword(s):

Optical Properties ◽

Crystal Growth ◽

Electron Diffraction ◽

Chemical Analysis ◽

Growth Surface ◽

Complete Disappearance ◽

X Ray ◽

Solid Crystal ◽

Wet Chemical ◽

Growth Features

AbstractA study of apatite crystals from the Asio mine, Japan, showed sectoral texture related to the growth of the crystal, and with optically biaxial properties within the sectors. Wet chemical analysis gave a composition Ca5(PO4)3(F0.64,OH0.38,Cl0.01)1.03 for the specimen.Additional diffraction spots were not observed in precession and oscillation X-ray photographs and electron diffraction photographs. Since the internal textures correlate with the surface growth features, it is suggested that the internal textures and the unusual optical properties were produced during nonequilibrium crystal growth. The fluorine/hydroxyl sites in hexagonal apatite are symmetrically equivalent in the solid crystal but, at a growth surface, this equivalence may be lost, resulting in a reduction of crystal symmetry. Heating of the apatite to about 850°C results in the almost complete disappearance of the optical anomalies due to disordering, which may be related to the loss of hydroxyl from the crystal.

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Probing bacterial cell wall growth by tracing wall-anchored protein complexes

Nature Communications ◽

10.1038/s41467-021-22483-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Yi-Jen Sun ◽

Fan Bai ◽

An-Chi Luo ◽

Xiang-Yu Zhuang ◽

Tsai-Shun Lin ◽

...

Keyword(s):

Cell Wall ◽

Cell Shape ◽

Bernoulli Shift ◽

Protein Complexes ◽

Axial Direction ◽

Cell Wall Growth ◽

Flagellar Motors ◽

Shift Map ◽

Dynamic Assembly ◽

Wall Growth

AbstractThe dynamic assembly of the cell wall is key to the maintenance of cell shape during bacterial growth. Here, we present a method for the analysis of Escherichia coli cell wall growth at high spatial and temporal resolution, which is achieved by tracing the movement of fluorescently labeled cell wall-anchored flagellar motors. Using this method, we clearly identify the active and inert zones of cell wall growth during bacterial elongation. Within the active zone, the insertion of newly synthesized peptidoglycan occurs homogeneously in the axial direction without twisting of the cell body. Based on the measured parameters, we formulate a Bernoulli shift map model to predict the partitioning of cell wall-anchored proteins following cell division.

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