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1.
Bull Exp Biol Med ; 158(3): 336-41, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25573364

RESUMEN

Toxic liver injury with the development of fibrosis and cirrhosis was modeled in Wistar rats by intragastric administration of 0.1 ml/kg CCl4 in combination with 5% ethanol with glucose 3 times a week for 6 weeks. The animals were treated with betulonic acid amide (50 mg/kg in Tween aqueous solution) and heptral (6 mg/kg) as hepatoprotective compounds. It was found that betulonic acid amide stimulated the regenerative response in hepatocytes under conditions of combined toxic exposure and promoted recovery of their qualitative and quantitative characteristics, which was accompanied by a significant decrease in the severity of liver fibrosis and the absence of cirrhotic transformation of the liver.


Asunto(s)
Tetracloruro de Carbono/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Etanol/toxicidad , Hígado/efectos de los fármacos , Hígado/metabolismo , Ácido Oleanólico/análogos & derivados , Animales , Femenino , Ácido Oleanólico/uso terapéutico , Ratas , Ratas Wistar
3.
Biofouling ; 29(2): 163-70, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23327438

RESUMEN

Despite the volume of work that has been conducted on the topic, the role of surface topography in mediating bacterial cell adhesion is not well understood. The primary reason for this lack of understanding is the relatively limited extent of topographical characterisation employed in many studies. In the present study, the topographies of three sub-nanometrically smooth titanium (Ti) surfaces were comprehensively characterised, using nine individual parameters that together describe the height, shape and distribution of their surface features. This topographical analysis was then correlated with the adhesion behaviour of the pathogenic bacteria Staphylococcus aureus and Pseudomonas aeruginosa, in an effort to understand the role played by each aspect of surface architecture in influencing bacterial attachment. While P. aeruginosa was largely unable to adhere to any of the three sub-nanometrically smooth Ti surfaces, the extent of S. aureus cell attachment was found to be greater on surfaces with higher average, RMS and maximum roughness and higher surface areas. The cells also attached in greater numbers to surfaces that had shorter autocorrelation lengths and skewness values that approached zero, indicating a preference for less ordered surfaces with peak heights and valley depths evenly distributed around the mean plane. Across the sub-nanometrically smooth range of surfaces tested, it was shown that S. aureus more easily attached to surfaces with larger features that were evenly distributed between peaks and valleys, with higher levels of randomness. This study demonstrated that the traditionally employed amplitudinal roughness parameters are not the only determinants of bacterial adhesion, and that spatial parameters can also be used to predict the extent of attachment.


Asunto(s)
Adhesión Bacteriana , Biopelículas , Nanopartículas del Metal/química , Pseudomonas aeruginosa/fisiología , Staphylococcus aureus/fisiología , Titanio/química , Carga Bacteriana , Simulación por Computador , Imagenología Tridimensional , Microscopía de Fuerza Atómica , Especificidad de la Especie , Propiedades de Superficie
4.
Chaos ; 23(2): 023120, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23822485

RESUMEN

We have studied a spontaneous self-organization dynamics in a closed, dissipative (in terms of guansine 5'-triphosphate energy dissipation), reaction-diffusion system of acentrosomal microtubules (those nucleated and organized in the absence of a microtubule-organizing centre) multitude constituted of straight and curved acentrosomal microtubules, in highly crowded conditions, in vitro. Our data give experimental evidence that cross-diffusion in conjunction with excluded volume is the underlying mechanism on basis of which acentrosomal microtubule multitudes of different morphologies (straight and curved) undergo a spatial-temporal demix. Demix is constituted of a bifurcation process, manifested as a slow isothermal spinodal decomposition, and a dissipative process of transient periodic spatio-temporal pattern formation. While spinodal decomposition is an energy independent process, transient periodic spatio-temporal pattern formation is accompanied by energy dissipative process. Accordingly, we have determined that the critical threshold for slow, isothermal spinodal decomposition is 1.0 ± 0.05 mg/ml of microtubule protein concentration. We also found that periodic spacing of transient periodic spatio-temporal patterns was, in the overall, increasing versus time. For illustration, we found that a periodic spacing of the same pattern was 0.375 ± 0.036 mm, at 36 °C, at 155th min, while it was 0.540 ± 0.041 mm at 31 °C, and at 275th min after microtubule assembly started. The lifetime of transient periodic spatio-temporal patterns spans from half an hour to two hours approximately. The emergence of conditions of macroscopic symmetry breaking (that occur due to cross-diffusion in conjunction with excluded volume) may have more general but critical importance in morphological pattern development in complex, dissipative, but open cellular systems.


Asunto(s)
Centrosoma/metabolismo , Microtúbulos/metabolismo , Modelos Biológicos , Análisis Espacio-Temporal , Animales , Bovinos , Guanosina Trifosfato/metabolismo , Cinética , Proteínas de Microtúbulos/metabolismo
5.
Biofouling ; 28(6): 539-50, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22686938

RESUMEN

Superhydrophobic titanium surfaces fabricated by femtosecond laser ablation to mimic the structure of lotus leaves were assessed for their ability to retain coccoid bacteria. Staphylococcus aureus CIP 65.8T, S. aureus ATCC 25923, S. epidermidis ATCC 14990T and Planococcus maritimus KMM 3738 were retained by the surface, to varying degrees. However, each strain was found to preferentially attach to the crevices located between the microscale surface features. The upper regions of the microscale features remained essentially cell-free. It was hypothesised that air entrapped by the topographical features inhibited contact between the cells and the titanium substratum. Synchrotron SAXS revealed that even after immersion for 50 min, nano-sized air bubbles covered 45% of the titanium surface. After 1 h the number of cells of S. aureus CIP 65.8T attached to the lotus-like titanium increased to 1.27×10(5) mm(-2), coinciding with the replacement of trapped air by the incubation medium.


Asunto(s)
Aire , Adhesión Bacteriana/fisiología , Cocos Grampositivos/fisiología , Interacciones Hidrofóbicas e Hidrofílicas , Lotus/microbiología , Titanio/química , Lotus/química , Hojas de la Planta/química , Hojas de la Planta/microbiología , Espectrometría Raman , Propiedades de Superficie
6.
Biochemistry (Mosc) ; 76(7): 791-6, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21999540

RESUMEN

Structure of the O-specific polysaccharide chain of the lipopolysaccharide (LPS) of Shewanella japonica KMM 3601 was elucidated. The initial and O-deacylated LPS as well as a trisaccharide representing the O-deacetylated repeating unit of the O-specific polysaccharide were studied by sugar analysis along with 1H and 13C NMR spectroscopy. The polysaccharide was found to contain a rare higher sugar, 5,7-diacetamido-3,5,7,9-tetradeoxy-D-glycero-D-talo-non-2-ulosonic acid (a derivative of 4-epilegionaminic acid, 4eLeg). The following structure of the trisaccharide repeating unit was established: →4)-α-4eLegp5Ac7Ac-(2→4)-ß-D-GlcpA3Ac-(1→3)-ß-D-GalpNAc-(1→.


Asunto(s)
Antígenos O/química , Shewanella/química , Secuencia de Carbohidratos , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Shewanella/inmunología , Azúcares Ácidos/análisis
7.
Kardiologiia ; 51(9): 35-41, 2011.
Artículo en Ruso | MEDLINE | ID: mdl-21943007

RESUMEN

AIM: To study clinical and pharmacoeconomical aspects of trimetazidine MD as a component of complex therapy of chronic heart failure (CHF) in patients with cardiac rhythm disturbances. MATERIAL AND METHODS: In 82 patients (67 men, 15 women, mean age 62.2+/-7.3 years) with II-III functional class (FC) of CHF we studied effect of addition of therapy with trimetazidine MB to standard therapy on CHF FC, parameters of Holter monitoring (HM) of ECG and treadmill test. In analysis of HM we considered number of isolated and paired ventricular extrasystoles (VE), episodes of nonsustained ventricular tachycardia (VT), duration of episodes of ST segment depression on 24-hour ECG. Pharmacoeconomical analysis of 2 therapy regimes was conducted by the method of calculation of cost/efficacy ratio for each parameter. Stabilization of state was achieved before study in all patients at the background of standard therapy with angiotensin converting enzyme inhibitors, cardiac glycosides, diuretics, beta-adrenoblockers. At the background of this therapy trimetazidine MB in the dose of 70 mg/day was added to 40 patients of group 1 while 42 patients of group 2 received standard therapy without trimetazidine MB. RESULTS: After 16 weeks of treatment CHF FC lowered 11% (<0.05) 10% (<0.05) in groups 1 and 2, respectively. According to data of HM numbers of VE decreased in group 1 by 57.6% (<0.05), in group 2 by 28.8% (<0.05), episodes of nonsustained VT--by 58.3% (<0,05) and 36.8% (<0.05), isolated VE--by 23.6% (>0.05) and 6.9% (>0.05), respectively. Duration of episodes of ST depression decreased 55.5% (<0.05) in group 1 and 23.3% (<0.05) in group 2. According to treadmill test maximal power of load in patients of group 1 rose 12.3% (<0.05), of group 2-6.7% (<0.05), total exercise duration rose 16.8% (<0.05) and 82% (<0.05), respectively. Cost/efficacy ratio expressed in roubles per 1% efficacy calculated for CHF FC was 2694 in group 1, 4095--in group 2; for maximal load power--2409 and 3667, respectively; for duration of episodes of ST segment depression--1665 and 1934, respectively; for dynamics of VE number--514 and 853, respectively. CONCLUSIONS: Supplementation of standard CHF therapy with therapy with metabolic cytoprotector trimetazidine MB allows to achieve more pronounced positive effect on CHF FC, exercise tolerance, and lowering of cardiac ectopic activity. Smallest cost efficacy ratio after addition of trimetazidine MB to standard therapy from pharmacoeconomical point of view evidence for advantages of this regime of therapy possessing smaller expenditures per unit of efficacy.


Asunto(s)
Arritmias Cardíacas/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Monitoreo Fisiológico , Trimetazidina , Anciano , Arritmias Cardíacas/complicaciones , Arritmias Cardíacas/diagnóstico , Enfermedad Crónica , Costos y Análisis de Costo , Manejo de la Enfermedad , Electrocardiografía , Prueba de Esfuerzo , Tolerancia al Ejercicio/efectos de los fármacos , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/economía , Monitoreo Fisiológico/métodos , Inducción de Remisión , Índice de Severidad de la Enfermedad , Trimetazidina/administración & dosificación , Trimetazidina/efectos adversos , Trimetazidina/economía , Vasodilatadores/administración & dosificación , Vasodilatadores/efectos adversos
8.
Biofouling ; 26(4): 461-71, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20358429

RESUMEN

Optical fibres have received considerable attention as high-density sensor arrays suitable for both in vitro and in vivo measurements of biomolecules and biological processes in living organisms and/or nano-environments. The fibre surface was chemically modified by exposure to a selective etchant that preferentially erodes the fibre cores relative to the surrounding cladding material, thus producing a regular pattern of cylindrical wells of approximately 2.5 mum in diameter and 2.5 mum deep. The surface hydrophobicity of the etched and non-etched optical fibres was analysed using the sessile pico-drop method. The surface topography was characterised by atomic force microscopy (AFM), while the surface chemistry was probed by time-of-flight secondary ion mass spectrometry (ToF-SIMS). Six taxonomically different bacterial strains showed a consistent preference for attachment to the nano-scale smoother (R(q) = 273 nm), non-etched fibre surfaces (water contact angle, theta = 106 degrees +/- 4 degrees). In comparison, the surfaces of the etched optical fibres (water contact angle, theta = 96 degrees +/- 10 degrees) were not found to be amenable to bacterial attachment. Bacterial attachment on the non-etched optical fibre substrata varied among different strains.


Asunto(s)
Adhesión Bacteriana , Fibras Ópticas/microbiología , Propiedades de Superficie
9.
Biofouling ; 25(7): 621-31, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20183121

RESUMEN

The retention patterns of five taxonomically different marine bacteria after attachment on two types of glass surfaces, as-received and chemically etched, have been investigated. Contact angle measurements, atomic force microscopy (AFM), scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), X-ray fluorescence spectroscopy (XRF) and X-ray photoelectron spectrometry (XPS) were employed to investigate the impact of nanometer scale surface roughness on bacterial attachment. Chemical modification of glass surfaces resulted in a approximately 1 nm decrease in the average surface roughness (R(a)) and the root-mean-squared roughness (R(q)) and in a approximately 8 nm decrease in the surface height and the peak-to-peak (R(max)) and the 10-point average roughness (R(z)). The study revealed amplified bacterial attachment on the chemically etched, nano-smoother glass surfaces. This was a consistent response, notwithstanding the taxonomic affiliation of the selected bacteria. Enhanced bacterial attachment was accompanied by elevated levels of secreted extracellular polymeric substances (EPS). An expected correlation between cell surface wettability and the density of the bacterial attachment on both types of glass surfaces was also reported, while no correlation could be established between cell surface charge and the bacterial retention pattern.


Asunto(s)
Alphaproteobacteria/crecimiento & desarrollo , Flavobacteriaceae/crecimiento & desarrollo , Gammaproteobacteria/crecimiento & desarrollo , Vidrio/química , Alphaproteobacteria/clasificación , Alphaproteobacteria/fisiología , Adhesión Bacteriana , Flavobacteriaceae/fisiología , Gammaproteobacteria/clasificación , Gammaproteobacteria/fisiología , Biología Marina , Ensayo de Materiales , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Nanoestructuras , Propiedades de Superficie
10.
Sud Med Ekspert ; 50(1): 31-4, 2007.
Artículo en Ruso | MEDLINE | ID: mdl-17338340

RESUMEN

The article describes the method of simultaneous detection of amitriptiline and nortriptilin in cadaveric blood using gas chromatography with mass-selective detection. Preparation includes liquid-liquid extraction and derivation with trifluoroacetic anhydride. Nortriptilin threshold of detectability in the blood is 0.02 mcg/ml, amitriptilin one--0.05 mcg/ml. The range of detectability--0.05-3.0 mcg/ml for both compounds. Maximal error of the compounds detectability was under 12.9% for concentrations 0.10 mcg/ml and 10.6% for concentrations 2.0 mcg/ml. The method was tested on expert material in forensic chemical examinations.


Asunto(s)
Amitriptilina/sangre , Antidepresivos Tricíclicos/sangre , Toxicología Forense/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Nortriptilina/sangre , Cadáver , Toxicología Forense/instrumentación , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Humanos , Sensibilidad y Especificidad
11.
Mikrobiol Z ; 68(4): 10-20, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17100323

RESUMEN

Two orange-pigmented Gram-positive, aerobic bacteria were isolated from enrichment culture during degradation of brown alga Fucus evanescens thalluses. In this work, atomic force microscopy (AFM) has been used to study the cell morphology. The non-contact mode imaging revealed unusual irregular coccoid shape of cells, possessing a single flagellum. Bacteria produced carotenoid pigments, were chemo-organotrophic, alkaliphilic and halo-tolerant growing well on nutrient media containing up to 15% NaCl. Growth temperature ranged from 5 to 45 degrees C. The DNA base compositions were 48 mol% G + C and the level of DNA similarity of two strains was conspecific (98%). A comparative phylogenetic analysis of 16S rRNA gene sequences revealed that the strain KMM 3738 tightly clustered with recently described Planococcus maritimus (99.9% 16S rRNA gene sequence similarity). DNA-DNA hybridisation experiments revealed that DNA from the KMM 3738 showed 12-15% and 16-35% of genetic relatedness with the DNA of type strains of the genera Planomicrobium and Planococcus, respectively, and 87% with DNA from Planococcus maritimus, indicating that new isolates belong to the later species.


Asunto(s)
Fucus/microbiología , Bacterias Grampositivas/aislamiento & purificación , Técnicas de Tipificación Bacteriana , ADN Bacteriano/análisis , Bacterias Grampositivas/genética , Bacterias Grampositivas/ultraestructura , Microscopía Electrónica de Transmisión , Filogenia , ARN Bacteriano/análisis , ARN Ribosómico 16S/análisis
12.
Mar Biotechnol (NY) ; 7(3): 173-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15906116

RESUMEN

An alkaline phosphatase with unusually high specific activity has been found to be produced by the marine bacterium Cobetia marina (strain KMM MC-296) isolated from coelomic liquid of the mussel Crenomytilus grayanus. The properties of enzyme, such as a very high specific activity (15000 DE U/1 mg of protein), no activation with divalent cations, resistance to high concentrations of inorganic phosphorus, as well as substrate specificity toward 5' nucleotides suggest that the enzyme falls in an intermediate position between unspecific alkaline phosphatases (EC 3.1.3.1) and 5' nucleotidases (EC 3.1.3.5).


Asunto(s)
5'-Nucleotidasa/aislamiento & purificación , Fosfatasa Alcalina/aislamiento & purificación , Halomonadaceae/enzimología , Mytilidae/microbiología , Animales , Concentración de Iones de Hidrógeno , Punto Isoeléctrico , Peso Molecular , Océano Pacífico , Especificidad por Sustrato
13.
Biosens Bioelectron ; 67: 321-6, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25201014

RESUMEN

The methylotrophic Pichia angusta VKM Y-2559 and the oleaginous Cryptococcus curvatus VKM Y-3288 yeast cells were immobilized in a bimodal silica-organic sol-gel matrix comprised of tetraethoxysilane (TEOS), the hydrophobic additive methyltriethoxysilane (MTES) and the porogen polyethylene glycol (PEG). Under carefully optimized experimental conditions, employing basic catalysts, yeast cells have become the nucleation centers for a silica-organic capsule assembled around the cells. The dynamic process involved in the formation of the sol-gel matrix has been investigated using optical and scanning electron microscopic techniques. The results demonstrated the influence of the MTES composition on the nature of the encapsulation of the yeast cells, together with the architecture of the three-dimensional (3D) sol-gel biomatrix that forms during the encapsulation process. A silica capsule was found to form around each yeast cell when using 85 vol% MTES. This capsule was found to protect the microorganisms from the harmful effects that result from exposure to heavy metal ions and UV radiation. The encapsulated P. angusta BKM Y-2559 cells were then employed as a biosensing element for the detection of methanol. The P. angusta-based biosensor is characterized by high reproducibility (Sr, 1%) and operational stability, where the biosensor remains viable for up to 28 days.


Asunto(s)
Técnicas Biosensibles , Cryptococcus/química , Metanol/aislamiento & purificación , Pichia/química , Catálisis , Polietilenglicoles/química , Polimetil Metacrilato/química , Porosidad , Silanos/química , Gel de Sílice/química
14.
Carbohydr Res ; 275(1): 147-54, 1995 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-7585719

RESUMEN

Capsular polysaccharide (CPS) was obtained by water-saline extraction of the Alteromonas sp. CMM 155. On the basis of solvolysis with anhydrous HF and 1H- and 13C-NMR spectral data, including NOE experiments, it was concluded that the capsular polysaccharide had the following structure containing novel N-acyl-amino sugar and bacillosamine residues: --> 3)-alpha-D-GalpNAc-(1 --> 4)-alpha-L-GalApNAc(1 --> 3)- alpha-D-QuipNAc4NAc-(1 --> 3)-beta-D-Quip4NAlaAc-(1 -->


Asunto(s)
Cápsulas Bacterianas/química , Bacterias Aerobias Gramnegativas/química , Oligosacáridos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular
15.
Carbohydr Res ; 313(1): 61-4, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9861701

RESUMEN

The structure of the O-specific polysaccharide from lipopolysaccharide of Pseudoalteromonas elyakovii sp. nov. CMM 162 on the basis of NMR data, Smith degradation and methylation study was elucidated as follows:-->2)-alpha-D-Glcp-(1-->4)-beta-D-GalpNAc-(1--> 3)-alpha-D-Galp-(1-->3)-beta-D-Galp-NAc-(1-->6)-alpha-D-Glcp-(1-->.


Asunto(s)
Bacterias Aerobias Gramnegativas/química , Antígenos O/química , Secuencia de Carbohidratos , Bacterias Aerobias Gramnegativas/clasificación , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular
16.
Carbohydr Res ; 299(1-2): 69-76, 1997 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-9129296

RESUMEN

A capsular polysaccharide was obtained from Alteromonas nigrifaciens IAM 13010T by saline extraction. On the basis of 1H and 13C NMR spectroscopy, including one-dimensional (1D) NOE spectroscopy, 2D rotating-frame NOE spectroscopy (ROESY), and 1H-detected heteronuclear 1H,13C multiple-quantum coherence (HMQC), it was concluded that the polysaccharide contained inter alia an acidic sugar, 3-deoxy-D-manno-octulosonic acid (Kdo), and a rare amino sugar, 2-acetamido-2,6-dideoxy-L-talose (L-6dTalNAc, N-acetylpneumosamine), and has a pentasaccharide repeating unit of the following structure: [equation: see text]


Asunto(s)
Bacterias Aerobias Gramnegativas/inmunología , Hexosaminas/análisis , Polisacáridos Bacterianos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Bacterias Aerobias Gramnegativas/química , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Oligosacáridos/química , Oligosacáridos/aislamiento & purificación , Polisacáridos Bacterianos/aislamiento & purificación , Azúcares Ácidos/análisis
17.
Carbohydr Res ; 333(1): 41-6, 2001 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-11423109

RESUMEN

O-specific polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of Pseudoalteromonas tetraodonis type strain IAM 14160(T) and studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, 1H,(13)C HMQC and HMBC experiments. The polysaccharide was found to consist of hexasaccharide repeating units containing one residue each of D-Gal, D-GlcA, D-GalNAc and D-GlcNAc and two residues of 3,6-dideoxy-L-xylo-hexose (colitose, Col) and having the following structure:In common with the polysaccharides of some other bacteria, the polysaccharide studied contains a tetrasaccharide fragment alpha-Colp-(1-->2)-beta-D-Galp-(1-->3)-[alpha-Colp-(1-->4)]-beta-D-GlcpNAc, which is a colitose ('3-deoxy-L-fucose') analogue of the Lewis(b) blood group antigenic determinant.


Asunto(s)
Desoxiazúcares/química , Gammaproteobacteria/química , Antígenos O/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Gammaproteobacteria/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Biología Marina , Datos de Secuencia Molecular
18.
Bioorg Khim ; 18(3): 418-21, 1992 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-1381922

RESUMEN

O-Specific polysaccharide composed of L-rhamnose and 2-acetamido-2-deoxy-D-mannose was obtained on mild acid degradation of the V. fluvialis lipopolysaccharide. On the basis of the 13C-NMR data and methylation studies, the following structure was suggested for the polysaccharide repeating unit: ----4)-alpha-L-Rhap-(1----3)-beta-D-ManpNAc-(1---- This structure was confirmed by calculations using known glycosidation effects on 13C chemical shifts.


Asunto(s)
Polisacáridos Bacterianos/química , Vibrio/metabolismo , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Antígenos O , Polisacáridos/química
19.
Bioorg Khim ; 19(3): 327-36, 1993 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-8489533

RESUMEN

An acidic capsular and an O-specific polysaccharide were isolated from the marine microorganism Alteromonas haloplanktis KMM 156. Both polysaccharides have the identical structure and are built up of tetrasaccharide repeating units, containing two residues of L-rhamnose as well as a 2-acetamido-2-deoxy-D-glucose and a 3-O-[(R)-1-carboxyethyl]-D-glucose (Glc3Lac) residue. On the basis of methylation studies, 1H- and 13C-NMR-spectroscopy including nuclear Overhauser effect and two-dimensional heteronuclear 13C/1H correlation spectroscopy, the following structure was suggested for the polysaccharide repeating unit: [formula: see text]


Asunto(s)
Bacterias Aerobias Gramnegativas/química , Polisacáridos Bacterianos/química , Secuencia de Carbohidratos , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular
20.
Bioorg Khim ; 19(7): 733-9, 1993 Jul.
Artículo en Ruso | MEDLINE | ID: mdl-8373453

RESUMEN

An acidic polysaccharide from Alteromonas sp. 4MC17 is built up of trisaccharide repeating units containing D-glucose, D-mannose and D-galacturonic acid residues. On the basis of methylation studies, 1H and 13C NMR-spectroscopy data, including two-dimensional homonuclear correlation spectroscopy and nuclear Overhauser effects, the following structure was suggested for the polysaccharide repeating unit: -->4)-beta-D-Glcp-(1-->4)-beta-D-GalpA-(1-->4)-beta-D-Manp-( 1-->.


Asunto(s)
Bacterias Aerobias Gramnegativas/química , Polisacáridos Bacterianos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Isótopos de Carbono , Hidrógeno , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular
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