Cellulose Synthesis in Detached Cotton Fibers

Tobacco primary cell wall and normal bacterial Acetobacter xylinum cellulose formation produced a 36.8±3Å triple-stranded left-hand helical microfibril in freeze-dried Pt-C replicas and in negatively stained preparations for TEM. As three submicrofibril strands exit the wall of Axylinum , they twist together to form a left-hand helical microfibril. This process is driven by the left-hand helical structure of the submicrofibril and by cellulose synthesis. That is, as the submicrofibril is elongating at the wall, it is also being left-hand twisted and twisted together with two other submicrofibrils. The submicrofibril appears to have the dimensions of a nine (l-4)-ß-D-glucan parallel chain crystalline unit whose long, 23Å, and short, 19Å, diagonals form major and minor left-handed axial surface ridges every 36Å.The computer generated optical diffraction of this model and its corresponding image have been compared. The submicrofibril model was used to construct a microfibril model. This model and corresponding microfibril images have also been optically diffracted and comparedIn this paper we compare two less complex microfibril models. The first model (Fig. 1a) is constructed with cylindrical submicrofibrils. The second model (Fig. 2a) is also constructed with three submicrofibrils but with a single 23 Å diagonal, projecting from a rounded cross section and left-hand helically twisted, with a 36Å repeat, similar to the original model (45°±10° crossover angle). The submicrofibrils cross the microfibril axis at roughly a 45°±10° angle, the same crossover angle observed in microflbril TEM images. These models were constructed so that the maximum diameter of the submicrofibrils was 23Å and the overall microfibril diameters were similar to Pt-C coated image diameters of ∼50Å and not the actual diameter of 36.5Å. The methods for computing optical diffraction patterns have been published before.

Download Full-text

Structural aspects of tracheary element differentiation in suspension cultures of Zinnia elegans

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155815 ◽

1989 ◽

Vol 47 ◽

pp. 768-769

Author(s):

C. H. Haigler ◽

A. W. Roberts

Keyword(s):

Tracheary Element ◽

Vesicle Fusion ◽

Zinnia Elegans ◽

Cellulose Synthesis ◽

Tracheary Elements ◽

Animal Cells ◽

Mesophyll Cells ◽

Fixation Techniques ◽

Localized Patterns ◽

Structural Aspects

Tracheary elements, the water-conducting cells in plants, are characterized by their reinforced walls that became thickened in localized patterns during differentiation (Fig. 1). The synthesis of this localized wall involves abundant secretion of Golgi vesicles that export preformed matrix polysaccharides and putative proteins involved in cellulose synthesis. Since the cells are not growing, some kind of endocytotic process must also occur. Many researchers have commented on where exocytosis occurs in relation to the thickenings (for example, see), but they based their interpretations on chemical fixation techniques that are not likely to provide reliable information about rapid processes such as vesicle fusion. We have used rapid freezing to more accurately assess patterns of vesicle fusion in tracheary elements. We have also determined the localization of calcium, which is known to regulate vesicle fusion in plant and animal cells.Mesophyll cells were obtained from immature first leaves of Zinnia elegans var. Envy (Park Seed Co., Greenwood, S.C.) and cultured as described previously with the following exceptions: (a) concentration of benzylaminopurine in the culture medium was reduced to 0.2 mg/l and myoinositol was eliminated; and (b) 1.75ml cultures were incubated in 22 x 90mm shell vials with 112rpm rotary shaking. Cells that were actively involved in differentiation were harvested and frozen in solidifying Freon as described previously. Fractures occurred preferentially at the cell/planchet interface, which allowed us to find some excellently-preserved cells in the replicas. Other differentiating cells were incubated for 20-30 min in 10(μM CTC (Sigma), an antibiotic that fluoresces in the presence of membrane-sequestered calcium. They were observed in an Olympus BH-2 microscope equipped for epi-fluorescence (violet filter package and additional Zeiss KP560 barrier filter to block chlorophyll autofluorescence).

Download Full-text

BRIEF-Primary Deposition of Grease-Free Carbon Black on Chopped Cotton Fibers

Industrial & Engineering Chemistry ◽

10.1021/ie50509a891 ◽

1952 ◽

Vol 44 (5) ◽

pp. 934-934

Author(s):

W Hart ◽

Jack Compton

Keyword(s):

Carbon Black ◽

Free Carbon ◽

Cotton Fibers

Download Full-text

Faculty Opinions recommendation of A receptor-like kinase mediates the response of Arabidopsis cells to the inhibition of cellulose synthesis.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1087788.540708 ◽

2007 ◽

Author(s):

Gwyneth Ingram

Keyword(s):

Cellulose Synthesis ◽

Receptor Like Kinase ◽

Arabidopsis Cells

Download Full-text

Faculty Opinions recommendation of Crystallographic snapshot of cellulose synthesis and membrane translocation.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717968121.793469459 ◽

2013 ◽

Author(s):

Ronald Kaback ◽

Lan Guan

Keyword(s):

Cellulose Synthesis ◽

Membrane Translocation

Download Full-text

Microstructure and physical properties of composite nonwovens produced by incorporating cotton fibers in elastic spunbond and meltblown webs for medical textiles

Journal of Industrial Textiles ◽

10.1177/15280837211004287 ◽

2021 ◽

pp. 152808372110042

Author(s):

Partha Sikdar ◽

Gajanan S Bhat ◽

Doug Hinchliff ◽

Shafiqul Islam ◽

Brian Condon

Keyword(s):

Tensile Strength ◽

Physical Properties ◽

Composite Structures ◽

High Surface ◽

High Surface Area ◽

Barrier Properties ◽

Cotton Fibers ◽

Adult Care ◽

Medical Textiles ◽

Improved Performance

The objective of this research was to produce elastomeric nonwovens containing cotton by the combination of appropriate process. Such nonwovens are in demand for use in several healthcare, baby care, and adult care products that require stretchability, comfort, and barrier properties. Meltblown fabrics have very high surface area due to microfibers and have good absorbency, permeability, and barrier properties. Spunbonding is the most economical process to produce nonwovens with good strength and physical properties with relatively larger diameter fibers. Incorporating cotton fibers into elastomeric nonwovens can enhance the performance of products, such as absorbency and comfort. There has not been any study yet to use such novel approaches to produce elastomeric cotton fiber nonwovens. A hydroentangling process was used to integrate cotton fibers into produced elastomeric spunbond and meltblown nonwovens. The laminated web structures produced by various combinations were evaluated for their physical properties such as weight, thickness, air permeability, pore size, tensile strength, and especially the stretch recovery. Incorporating cotton into elastic webs resulted in composite structures with improved moisture absorbency (250%-800%) as well as good breathability and elastic properties. The results also show that incorporating cotton can significantly increase tensile strength with improved spontaneous recovery from stretch even after the 5th cycle. Results from the experiments demonstrate that such composite webs with improved performance properties can be produced by commercially used processes.

Download Full-text