Even Visually Intact Cell Walls in Waterlogged Archaeological Wood Are Chemically Deteriorated and Mechanically Fragile: A Case of a 170 Year-Old Shipwreck

Structural and chemical deterioration and its impact on cell wall mechanics were investigated for visually intact cell walls (VICWs) in waterlogged archaeological wood (WAW). Cell wall mechanical properties were examined by nanoindentation without prior embedding. WAW showed more than 25% decrease of both hardness and elastic modulus. Changes of cell wall composition, cellulose crystallite structure and porosity were investigated by ATR-FTIR imaging, Raman imaging, wet chemistry, 13C-solid state NMR, pyrolysis-GC/MS, wide angle X-ray scattering, and N2 nitrogen adsorption. VICWs in WAW possessed a cleavage of carboxyl in side chains of xylan, a serious loss of polysaccharides, and a partial breakage of β-O-4 interlinks in lignin. This was accompanied by a higher amount of mesopores in cell walls. Even VICWs in WAW were severely deteriorated at the nanoscale with impact on mechanics, which has strong implications for the conservation of archaeological shipwrecks.

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The effects of thermal treatment on the nanomechanical behavior of bamboo (Phyllostachys pubescens Mazel ex H. de Lehaie) cell walls observed by nanoindentation, XRD, and wet chemistry

Holzforschung ◽

10.1515/hf-2016-0124 ◽

2017 ◽

Vol 71 (2) ◽

pp. 129-135 ◽

Cited By ~ 15

Author(s):

Yanjun Li ◽

Chengjian Huang ◽

Li Wang ◽

Siqun Wang ◽

Xinzhou Wang

Keyword(s):

Cell Wall ◽

Thermal Treatment ◽

Cell Walls ◽

Treatment Time ◽

Lignin Content ◽

Phyllostachys Pubescens ◽

X Ray Diffraction ◽

Wet Chemistry ◽

X Ray ◽

Wet Chemical

Abstract The effects of thermal treatment of bamboo at 130, 150, 170, and 190°C for 2, 4, and 6 h were investigated in terms of changes in chemical composition, cellulose crystallinity, and mechanical behavior of the cell-wall level by means of wet chemical analysis, X-ray diffraction (XRD), and nanoindentation (NI). Particularly, the reduced elastic modulus (Er), hardness (H), and creep behavior were in focus. Both the temperature and treatment time showed significant effects. Expectedly, the hemicelluloses were degraded and the relative lignin content was elevated, while the crystallinity of the cellulose moiety was increased upon thermal treatment. The Er and H data of the cell wall were increased after 6 h treatment at 190°C, from 18.4 to 22.0 GPa and from 0.45 to 0.65 GPa, respectively. The thermal treatment led to a decrease of the creep ratio (CIT) under the same conditions by ca. 28%. The indentation strain state (εi) also decreased significantly after thermal treatment during the load-holding stage.

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Synthesis and characterisation of lignin-like oligomers as a bio-inspired consolidant for waterlogged archaeological wood

Pure and Applied Chemistry ◽

10.1515/pac-2016-0814 ◽

2016 ◽

Vol 88 (10-11) ◽

pp. 969-977 ◽

Cited By ~ 11

Author(s):

Emily McHale ◽

Susan Braovac ◽

Calin C. Steindal ◽

Richard B. Gillis ◽

Gary G. Adams ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Ethyl Acetate ◽

Cell Walls ◽

Water Soluble ◽

Wood Structure ◽

New Materials ◽

Archaeological Wood ◽

Waterlogged Archaeological Wood ◽

Maximum Water ◽

Maximum Water Content

AbstractThe development of new materials for the consolidation of waterlogged archaeological wood from sustainable sources is an important area of research, as the most widely used consolidant today is petroleum based. Ideally a new consolidant will interact with the existing wood structure, ensuring maximum compatibility. Lignin is often the major component remaining in archaeological wood, as it is less susceptible to degradation than holocellulose. Therefore, in order to maximise the potential for interaction with the wood cells, lignin-like oligomers have been synthesized from isoeugenol using a water soluble copper salen catalyst at pH 10, giving a weight average Mw of 1.6 kDa. Analysis by NMR spectroscopy has shown that the oligomers have a lignin-like structure with β-O-4′, β-β′ and β-5′ connections. A 10 w/w% solution of the oligomers in ethyl acetate was found to thoroughly penetrate 1 cm3 samples of waterlogged archaeological wood (density of 0.146 g/mL, maximum water content of 620%) after 14 days impregnation, as determined by FTIR spectroscopy. No impregnation material could be seen by SEM, suggesting that it coats the cell walls upon drying. This indicates that dehydrogenated polymers penetrate waterlogged archaeological wood well and have the potential to be developed into consolidants.

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A SEROLOGICAL STUDY OF CELL WALLS OF CERTAIN LACTIC ACID BACTERIA

Canadian Journal of Microbiology ◽

10.1139/m62-084 ◽

1962 ◽

Vol 8 (5) ◽

pp. 629-637

Author(s):

K. L. Chung ◽

Roma Z. Hawirko

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Intact Cell ◽

Synthetic Medium ◽

Specific Cell ◽

Intact Cells ◽

Common Antigens ◽

Species Specific ◽

Relationship Of ◽

The Relationship

From three species of Lactobacillus and three species of Streptococcus, cultured in a synthetic medium, cell walls were isolated following sonic disintegration and purified by washing. Sera against each species were prepared by injecting three rabbits with cell walls, and three with intact cells. Reciprocal agglutination tests were carried out with unabsorbed and absorbed antisera. More kinds of antibodies were detected with cell-wall antisera than with intact-cell antisera. Many species in the two genera shared common antigens. S. faecalis was the exception. Certain antigens believed to be complex haptens in nature reacted with heterologous antisera. Haemagglutination of tanned erythrocytes sensitized with a particulate cell-wall suspension showed fewer cross reactions than agglutination of intact-cell suspensions.The evidence presented shows the possibility of using antisera against species-specific cell-wall antigens for the identification of these species. The relationship of these species is discussed.

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The derivation of the cellulose microfibril angle by small-angle X-ray scattering from structurally characterized softwood cell-wall populations

Journal of Applied Crystallography ◽

10.1107/s0021889805008319 ◽

2005 ◽

Vol 38 (3) ◽

pp. 505-511 ◽

Cited By ~ 6

Author(s):

Kenneth M. Entwistle ◽

Stephen J. Eichhorn ◽

Namasivayam Navaranjan

Keyword(s):

Cell Wall ◽

Standard Deviation ◽

Intensity Distribution ◽

Cell Walls ◽

Radial Direction ◽

Microfibril Angle ◽

Scattered Intensity ◽

X Ray ◽

The Real ◽

X Ray Scattering

A method is presented for the measurement, using small-angle X-ray scattering (SAXS), of the microfibril angle and the associated standard deviation for the cellulose microfibrils in the S2 layer of the cell walls of softwood specimens. The length and orientation of over 1000 cell walls in the irradiated volume of the specimen are measured using quantitative image analysis. From these data are calculated the azimuthal variation of the scattered intensity. The calculated values are compared with the measured values. The undetermined parameters in the analysis are the microfibril angle (M) and the standard deviation (σΦ) of the intensity distribution arising from the wandering of the fibril orientation about the mean value. The two parameters are varied to give the best fit between the calculated and the measured values. Six separate pairs of values are determined for six different values of the angle of incidence of the X-ray beam relative to the normal to the radial direction in the specimen. The results show good agreement. The azimuthal distribution of scattered intensity for the real cell-wall structure is compared with that calculated for an assembly of rectangular cells with the same ratio of transverse to radial cell-wall lengths. Despite the existence of marked differences in the intensity distributions around the zero azimuth angle, the position of the extreme flanks of the distribution is very close for the real and the rectangular cells. This means that useful values of the microfibril angle can be obtained from the curve for the real cells using the Meylan parameter T derived by drawing tangents to the flanks of the intensity distribution and using M = kT. The value of k is M/(M + 2σΦ). Since both of these parameters are determined in the work now described, k is also determined. It is also demonstrated that for β = 45° (where β is the angle between the plane face of the wood specimens and the radial direction) the peaks in the azimuthal intensity distribution for the real and the rectangular cells coincide. If this peak position is Φ45, then the microfibril angle can be determined from the relation M = tan−1(tanΦ45/cos45°), which is precise for rectangular cells.

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The role of plant cell wall encapsulation and porosity in regulating lipolysis during the digestion of almond seeds

Food & Function ◽

10.1039/c5fo00758e ◽

2016 ◽

Vol 7 (1) ◽

pp. 69-78 ◽

Cited By ~ 39

Author(s):

Myriam M. L. Grundy ◽

Frédéric Carrière ◽

Alan R. Mackie ◽

David A. Gray ◽

Peter J. Butterworth ◽

...

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Wall ◽

Intact Cell ◽

Lipid Digestion

Intact cell walls of almond prevent lipase penetration thus hindering lipid digestion.

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Interactions between Different Organosilicons and Archaeological Waterlogged Wood Evaluated by Infrared Spectroscopy

Forests ◽

10.3390/f12030268 ◽

2021 ◽

Vol 12 (3) ◽

pp. 268

Author(s):

Carmen-Mihaela Popescu ◽

Magdalena Broda

Keyword(s):

Cell Wall ◽

Fourier Transform ◽

Infrared Spectroscopy ◽

Chemical Modification ◽

Fourier Transform Infrared Spectroscopy ◽

Fourier Transform Infrared ◽

Organosilicon Compounds ◽

Structural Characterisation ◽

Archaeological Wood ◽

Waterlogged Archaeological Wood

The goal of the study was to characterise chemical interactions between waterlogged archaeological wood and organosilicon compounds applied for its conservation to shed lights on the mechanism of wood dimensional stabilisation by the chemicals. Two alkoxysilanes (methyltrimethoxysilane and (3-mercaptopropyl) trimethoxysilane) and a siloxane (1,3-bis(diethylamino)-3-propoxypropanol)-1,1,3,3-tetramethyldisiloxane) were selected for the research since they already have been proven to effectively stabilise waterlogged wood upon drying. Fourier transform infrared spectroscopy was used for structural characterisation of the degraded wood and evaluation of reactivity of the applied chemicals with polymers in the wooden cell wall. The results obtained clearly show much stronger interactions in the case of alkoxysilanes than the siloxane, suggesting a different mechanism of wood stabilisation by these compounds. The results of this study together with other data obtained in our previous research on stabilisation of waterlogged archaeological wood with organosilicon compounds allow the conclusion that the mechanism of waterlogged wood stabilisation by the used alkoxysilanes is based on bulking the cell wall by silane molecules and wood chemical modification, while in the case of the applied siloxane, it builds upon filling the cell lumina.

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Application of Small-Angle X-Ray Scattering to Predict Microfibril Angle in Acacia mangium Wood

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.173.72 ◽

2010 ◽

Vol 173 ◽

pp. 72-77

Author(s):

Tabet A. Tamer ◽

Aziz Abdul Haji Fauziah ◽

Radiman Shahidan

Keyword(s):

Cell Wall ◽

Standard Deviation ◽

Intensity Distribution ◽

Small Angle ◽

Cell Walls ◽

Microfibril Angle ◽

Acacia Mangium ◽

Cellulose Microfibrils ◽

X Ray ◽

X Ray Scattering

Partially crystalline cellulose microfibrils are wound helically around the longitudinal axis of the wood cell. A method is presented for the measurement, using small-angle X-ray scattering (SAXS), of the microfibril angle, (MFA) and the associated standard deviation for the cellulose microfibrils in the S2 layer of the cell walls of Acacia mangium wood. The length and orientation of the microfibrils of the cell walls in the irradiated volume of the thin samples are measured using SAXS and scanning electron microscope, (SEM). The undetermined parameters in the analysis are the MFA, (M) and the standard deviation (σФ) of the intensity distribution arising from the wandering of the fibril orientation about the mean value. Nine separate pairs of values are determined for nine different values of the angle of the incidence of the X-ray beam relative to the normal to the radial direction in the sample. The results show good agreement. The curve distribution of scattered intensity for the real cell wall structure is compared with that calculated with that assembly of rectangular cells with the same ratio of transverse to radial cell wall length. It is demonstrated that for β = 45°, the peaks in the curve intensity distribution for the real and the rectangular cells coincide. If this peak position is Ф45, Then the MFA can be determined from the relation M = tan-1 (tan Ф45 / cos 45°), which is precise for rectangular cells.

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Bactericidal/Permeability-Increasing Protein Inhibits Growth of a Strain of Acholeplasma laidlawii and L Forms of the Gram-Positive Bacteria Staphylococcus aureus andStreptococcus pyogenes

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.43.9.2314 ◽

1999 ◽

Vol 43 (9) ◽

pp. 2314-2316 ◽

Cited By ~ 19

Author(s):

Arnold H. Horwitz ◽

Robert E. Williams ◽

Pei-Syan Liu ◽

Rossana Nadell

Keyword(s):

Staphylococcus Aureus ◽

Cell Wall ◽

Streptococcus Pyogenes ◽

Cell Walls ◽

Intact Cell ◽

Inhibitory Effects ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Acholeplasma Laidlawii ◽

Growth Inhibitory

ABSTRACT Bactericidal/permeability-increasing protein (BPI) inhibited growth of cell wall-deficient Acholeplasma laidlawii and L forms of certain strains of Staphylococcus aureus andStreptococcus pyogenes. However, the same strains ofS. aureus and S. pyogenes with intact cell walls were not susceptible to the growth-inhibitory effects of BPI.

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Cell wall integrity signaling regulates cell wall regeneration via transcriptional activation in Chlamydomonas reinhardtii

10.1101/543280 ◽

2019 ◽

Author(s):

Evan Cronmiller ◽

Deepak Toor ◽

Nai Chun Shao ◽

Thamali Kariyawasam ◽

Ming Hsiu Wang ◽

...

Keyword(s):

Cell Wall ◽

Transcriptional Activation ◽

Cell Walls ◽

De Novo ◽

Intact Cell ◽

Gene Activation ◽

Cell Wall Integrity ◽

Luciferase Reporter ◽

Mrna Accumulation ◽

Signaling Mechanisms

AbstractAn intact cell wall is critical for protecting the cell from osmotic challenges and harmful environments. Signaling mechanisms are necessary to monitor cell wall integrity and to regulate cell wall production and remodeling during growth and division cycles. The green alga, Chlamydomonas, has a proteinaceous cell wall of defined structure that is readily removed by gametolysin (g-lysin), a metalloprotease released during sexual mating. Naked cells treated with g-lysin induce the mRNA accumulation of > 100 cell wall-related genes within an hour, offering a system to study signaling and regulatory mechanisms for de novo cell wall assembly. Combining quantitative RT-PCR and luciferase reporter assays to probe transcript accumulation and promoter activity, we revealed that up to 500-fold upregulation of cell wall-related genes was driven at least partly by transcriptional activation upon g-lysin treatment. To investigate how naked cells trigger this rapid transcriptional activation, we tested whether osmotic stress and cell wall integrity are involved in this process. Under a constant hypotonic condition, comparable levels of cell wall-gene activation were observed by g-lysin treatment. In contrast, cells in an iso- or hypertonic condition showed up to 80% reduction in the g-lysin-induced gene activation, suggesting that hypotonic conditions are required for full-scale responses to g-lysin treatment. To test whether mechanical perturbation is involved, we isolated and examined a new set of cell wall mutants with defective or little cell walls. All cell wall mutants examined showed a constitutive upregulation of cell wall-related genes at the level, which would only be achieved by the g-lysin treatment in wild-type cells. Our study suggests a signaling that monitors mechanical defects of cell walls and regulates cell wall-gene expression in Chlamydomonas, which may relate to cell wall integrity signaling mechanisms in plants.

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STUDIES ON THE CHEMICAL STRUCTURE OF THE STREPTOCOCCAL CELL WALL

Journal of Experimental Medicine ◽

10.1084/jem.114.1.127 ◽

1961 ◽

Vol 114 (1) ◽

pp. 127-140 ◽

Cited By ~ 91

Author(s):

Richard M. Krause ◽

Maclyn McCarty

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Chemical Structure ◽

Soluble Fraction ◽

Intact Cell ◽

Insoluble Residue ◽

Streptococcal Cell Wall ◽

Variant Cell ◽

Group A ◽

Characteristic Group

Lysis of trypsinized Group A streptococcal cell walls with phage-associated lysin releases into solution dialyzable and non-dialyzable mucopeptide fractions composed of N-acetylglucosamine, N-acetylmuramic acid and alanine, glutamic acid, lysine, and glycine in addition to the characteristic group-specific carbohydrate. The latter substance contains appreciable amounts of N-acetylmuramic acid and the amino acids as well as N-acetylglucosamine and rhamnose. Hot formamide extraction of the cell walls results in a soluble fraction of group-specific carbohydrate and an insoluble residue. The Group A carbohydrate in this instance is composed of rhamnose and N-acetylglucosamine. The composition of the insoluble residue is similar to that of the mucopeptide fractions released from the cell wall by phage-associated lysin. This residue was shown by electron microscopy to be composed of discrete discs which appear similar in structure to the intact cell wall. The specific carbohydrate obtained by hot formamide extraction of Group A-variant cell walls was composed almost exclusively of rhamnose. The residue fraction was similar to that of Group A. The residue of cell walls extracted with hot formamide is extensively solubilized not only by phage-associated lysin and S. albus enzyme, but also by lysozyme, which has no measurable effect on the intact streptococcal cell wall.

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