Resistant biomacromolecules as major contributors to kerogen

1991 ◽  
Vol 333 (1268) ◽  
pp. 329-337 ◽  
Keyword(s):  
Cell Walls ◽  
Chemical Characterization ◽  
Type I ◽  
Electron Microscopic ◽  
Alternative Source ◽  
Plant Cuticles ◽  
Microscopic Studies ◽  
Water Plants ◽  
Waxy Crude Oils

Current research concerning the chemical characterization of organic macromolecules present in wellpreserved fossilized materials with known morphologies revealed by (electron) microscopic studies results in the recognition of unknown, resistant biomacromolecules in a variety of organisms. It is shown that highly aliphatic, non-saponifiable biomacromolecules in cell walls of algae (algaenans) have unique structures, probably as a result of different biosynthetic pathways and that they consist of n -alkyl-, isoprenoid and tricyclic alkyl units. It is also becoming clear that algaenans are structurally different from the highly aliphatic, non-saponifiable biomacromolecules occurring in plant cuticles (cutans), periderm tissue (suberans), some sporopollenins and in tegmens of seeds of water plants. All these types of aliphatic biomacromolecules are highly resistant and therefore selectively preserved in the geosphere. In particular, Type I and II kerogens consist mainly, in some cases exclusively, of these aliphatic biomacromolecules. Polysesquiterpenoids and polyditerpenoids occur in fresh and fossil angiosperm and gymnosperm resins respectively and also show resistant behaviour in the geosphere. Some waxy crude oils contain large amounts of compounds derived from these substances after thermal cracking. A completely new polyphenol type of biomacromolecule was encountered in several fossilized outer walls of seeds (testae) of water plants. Preliminary results indicate that this phenolic biomacromolecule is an alternative source of phenolic moieties in lignites and coals. The significance of lignin as a source of phenolic moieties in subsurface organic matter (e.g. vitrinites) is probably overestimated.

Microstructural and Chemical Characterization of Ordered Structure in Yttrium Doped Ceria

2013 ◽  
Vol 19 (1) ◽  
pp. 102-110 ◽  
Author(s):  
Pengfei Yan ◽  
Toshiyuki Mori ◽  
Yuanyuan Wu ◽  
Zhimin Li ◽  
Graeme John Auchterlonie ◽  
...  
Keyword(s):  
Chemical Characterization ◽  
Electron Microscopic Observation ◽  
Doped Ceria ◽  
Electron Microscopic ◽  
Ordered Structures ◽  
Transmission Electron ◽  
Vacancy Ordering ◽  
Crystal Model ◽  
Electron Energy Loss

AbstractThe ordered structures in different doping levels (x = 0.1, 0.15, 0.2, 0.25, 0.3) of yttrium doped ceria (YDC, Ce(1−x)YxO2−δ) electrolytes were investigated by electron diffraction, high-resolution transmission electron microscopy (TEM), scanning TEM, and electron energy loss spectroscopy. Oxygen vacancy ordering was experimentally confirmed within the ordered structures. With increasing the doping level, the concentration of trivalent Ce cations was increased in YDC samples and such trivalent Ce cations were supposed to mainly exist in the ordered structures. Based on our electron microscopic observation and microanalysis, a crystal model for the ordered structures is proposed.

Characterization of Electrophoretic Lipoprotein Fractions: Immunochemical and Electron Microscopic Studies

1972 ◽  
Vol 18 (6) ◽  
pp. 534-538
Author(s):  
Mario Werner ◽  
Albert L Jones
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Electrophoretic Pattern ◽  
Electron Microscopic ◽  
Lipoprotein Subfractions ◽  
New Techniques ◽  
Microscopic Studies ◽  
Insight Into

Abstract To improve the characterization of electrophoretic lipoprotein subfractions, we developed two new techniques for analyzing lipoproteins after electrophoresis on thin agarose layers. Overlay with antisera exactly localizes specific apoproteins without any distortion caused by antigen diffusion; electron microscopy of eluted fractions determines the varying particle-size distribution. Applied together, these methods can detect individual differences between hyperlipemic samples that are not immediately apparent in the electrophoretic pattern, and should provide valuable new insight into the classification of hyperlipoproteinemias.

Comparative Chemical Characterization of Pigmented and Less Pigmented Cell Walls of Alternaria tenuissima

2005 ◽  
Vol 51 (6) ◽  
pp. 399-401 ◽  
Author(s):  
Kankipati Hara Kishore ◽  
Sanjit Kanjilal ◽  
Sunil Misra ◽  
Chinnathimma Rajagopal Reddy ◽  
Upadyayula Suryanarayana Murty
Keyword(s):  
Cell Walls ◽  
Chemical Characterization ◽  
Alternaria Tenuissima

Extraction and Partial Characterization of Pepsin-Soluble Collagens from the Skin of Amiurus Nebulosus

2011 ◽  
Vol 236-238 ◽  
pp. 2926-2934 ◽  
Author(s):  
Li Li Chen ◽  
Li Zhao ◽  
Hua Liu ◽  
Run Feng Wu
Keyword(s):  
Type I Collagen ◽  
Type I ◽  
Alternative Source ◽  
Soluble Collagen ◽  
Acid Soluble Collagen ◽  
Sds Page ◽  
Skin Collagen ◽  
Maximal Yield ◽  
Pepsin Soluble Collagen

Pepsin-soluble collagen (PSC) was successfully extracted from the skin of Amiurus nebulosus. The skin of Amiurus nebulosus was immersed in 0.3 mol/L acetic acid (1: 20, m: V) for 6 h at 37°C, while pepsin was added, at a level of 5000U/g dosage of defatted skin. The maximal yield of the collagen was 97.44%, which was higher than that of acid-soluble collagen (ASC) at 62.05%. Some properties of pepsin-soluble collagens from the skin of Amiurus nebulosus were characterized. Amino acid composition and SDS-PAGE suggested that the collagen might be classified as type I collagen. Moreover, FTIR investigations showed the existence of helical arrangements in PSC of Amiurus nebulosus skin of collagen. There is a possibility to use Amiurus nebulosus skin collagen as an alternative source of collagen for industrial purposes and subsequently it may maximize the economical value of the fish.

scholarly journals Differential distributions in tissues and efficacies of aztreonam and ceftazidime and in vivo bacterial morphological changes following treatment.

1997 ◽  
Vol 41 (2) ◽  
pp. 401-409 ◽  
Author(s):  
A Turcotte ◽  
M Simard ◽  
N J Morin ◽  
D Beauchamp ◽  
M G Bergeron
Keyword(s):  
Cell Walls ◽  
Morphological Changes ◽  
Enterobacter Cloacae ◽  
Control Group ◽  
Electron Microscopic ◽  
Penetration Ratio ◽  
Microscopic Studies ◽  
Bow Tie ◽  
Fibrin Clots

The differential tissue distributions of aztreonam and ceftazidime within fibrin clots infected with Pseudomonas aeruginosa, Enterobacter cloacae, and Serratia marcescens, their efficacies, and the in vivo bacterial morphological changes induced by these drugs were evaluated. Rabbits were given intravenously a single dose of 100 mg of either agents/kg of body weight. In the cores of the clots, the peak levels of both drugs were much lower than those observed in the peripheries and in serum. Aztreonam's half-lives within the peripheries and in the cores of the fibrin clots were up to six times higher than observed in serum, while ceftazidime's half-lives in clots were twice that observed in serum. This resulted in a much greater penetration ratio for aztreonam than for ceftazidime. Both drugs controlled the growth of P. aeruginosa in vivo, but E. cloacae and S. marcescens responded better to ceftazidime. Morphological changes were more abundant in the peripheries than in the cores of the clots. In the control group, P. aeruginosa's morphology in the cores was different than that in the peripheries of the clots. Against P. aeruginosa, aztreonam did induce morphological changes in the cores while ceftazidime did not. Electron microscopic studies revealed that morphological changes associated with aztreonam seemed different than those of ceftazidime. Along with elongation of bacteria, more bow tie and herniated bacteria were observed with aztreonam. Though both agents selectively affect PBP 3, as manifested by elongated bacteria, they induce in the peripheries of the clots thickening, breaks, and detachment in bacterial cell walls, alterations which are generally associated with antibiotics affecting PBP 1a and 1b.

scholarly journals Type I Dyserythropoietic Anemia in an Elderly Patient

Blood ◽  
1974 ◽  
Vol 44 (4) ◽  
pp. 495-500 ◽  
Author(s):  
Jorge E. Maldonado ◽  
Howard F. Taswell
Keyword(s):  
Elderly Patient ◽  
Bone Marrow ◽  
Type I ◽  
Electron Microscopic ◽  
Microscopic Studies

Abstract A 58-yr-old woman is described in whom light and electron microscopic studies of bone marrow revealed the typical features of type I dyserythropoietic anemia. This form of anemia may be first diagnosed late in life, and caution should be exerted to avoid its confusion with preleukemia or erythroleukemia.

scholarly journals Dipotassium tetramethyl osmate: a stain for electron microscopy.

1975 ◽  
Vol 23 (2) ◽  
pp. 123-127 ◽  
Author(s):  
C C Hinckley ◽  
J A Murphy
Keyword(s):  
Electron Microscopy ◽  
Cell Walls ◽  
Cell Ultrastructure ◽  
Outer Cell ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Methanol Solutions ◽  
Microscopic Studies ◽  
Cell Storage

Methanol solutions of dipotassium tetramethyl osmate (DTMO) have been found to be useful as general stains in electron microscopic studies of plant and fungal ultrastructure. The stain solutions are easy to prepare, stable when anhydrous and convenient to use. Although generally similar in staining to lead citrate stains, some elements of cell ultrastructure appear different with dipotassium tetramethyl osmate staining, particularly the outer cell walls of fungi. Indications of specific precipitate-producing reactions in cell storage areas are observed.

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