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1.
Skin Res Technol ; 22(3): 325-33, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26346940

RESUMEN

BACKGROUND/PURPOSE: Ultraviolet (UV) radiation is responsible for sunburns, skin cancer, photoaging, and the production of reactive oxygen species (ROS). The awareness on preventing these deleterious effects made the use of anti-UVB formulations an important part of population habits; however, despite the availability of several antioxidants capable of ROS scavenging, the pharmaceutical market lacks products associating UV filters with natural compounds of proven efficacy. Here, we investigated the effect of rutin, a flavonoid with antioxidant activity, associated with UVB filters in dermocosmetic preparations. METHODS: Formulations were assessed through its antioxidant activity, in vitro photoprotective effectiveness, photostability, and in vivo skin tolerance (hydration, transepidermal water loss, and erythema). RESULTS: Samples containing rutin were compatible with the human skin and presented a pronounced antioxidant potential, with scavenging activity values 75% higher than the ones containing only UVB filters. Although rutin could not prevent the sunscreens photodegradation post-irradiation, the bioactive compound significantly increased the formulations critical wavelengths, showing a photoprotective gain, especially in the UVA range. CONCLUSION: In conclusion, the absorption in the UVA range, coupled with ROS scavenging potential, proved the positive effect of rutin applied to anti-UVB formulations, making this bioactive compound a promising candidate for photoprotection improvement.


Asunto(s)
Protectores contra Radiación/administración & dosificación , Rutina/administración & dosificación , Fenómenos Fisiológicos de la Piel/efectos de los fármacos , Fenómenos Fisiológicos de la Piel/efectos de la radiación , Protectores Solares/administración & dosificación , Rayos Ultravioleta/efectos adversos , Absorción de Radiación/efectos de los fármacos , Adulto , Antioxidantes/metabolismo , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Sinergismo Farmacológico , Femenino , Filtración/métodos , Humanos , Piel/efectos de los fármacos , Piel/efectos de la radiación , Absorción Cutánea/efectos de los fármacos , Absorción Cutánea/fisiología , Absorción Cutánea/efectos de la radiación , Pérdida Insensible de Agua/efectos de los fármacos , Pérdida Insensible de Agua/fisiología , Pérdida Insensible de Agua/efectos de la radiación
2.
Biochim Biophys Acta ; 1419(1): 97-104, 1999 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-10366675

RESUMEN

Bacillus subtilis was grown at its growth temperature limits and at various temperatures in between the lower and upper growth temperature boundary. Liposomes were made of the extracted membrane lipids derived from these cells. The headgroup composition of the cytoplasmic membrane lipids did not differ significantly at the lower (13 degrees C) and upper (50 degrees C) temperature boundary. The averaged lipid acyl chain length, degree of saturation, and ratio of iso- and anteiso-branched fatty acids increased with the temperature. At the temperature of growth, the membranes were in a liquid-crystalline phase, but liposomes derived from cells grown at 13 degrees C were almost threefold more viscous than those derived from 50 degrees C grown cells. The temperature dependence of the proton permeability of the liposomes was determined using the acid-pulse method with monitoring of the outside pH with the fluorescent probe pyranine. The proton permeability of each liposome preparation increased with the temperature. However, the proton permeability of the liposomes at the growth temperature of the cells from which the lipids were derived was almost constant. These data indicate that the growth temperature dependent variation in lipid acyl chain composition permits maintenance of the proton permeability of the cytoplasmic membrane. This 'homeo-proton permeability adaptation' precludes futile cycling of protons at higher growth temperatures and allows cells to sustain the proton motive force as a driving force for essential energy transducing processes.


Asunto(s)
Bacillus subtilis/fisiología , Lípidos de la Membrana/metabolismo , Protones , Anisotropía , Bacillus subtilis/metabolismo , Permeabilidad de la Membrana Celular , Homeostasis , Membranas Intracelulares/metabolismo , Liposomas/química , Lípidos de la Membrana/aislamiento & purificación , Fosfolípidos/metabolismo , Temperatura
3.
FEBS Lett ; 352(3): 327-30, 1994 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-7925995

RESUMEN

A HIPIP-type center was discovered in intact membranes of the thermohalophilic aerobe Rhodothermus marinus. In both the membrane-bound state and after detergent solubilization and partial purification, this center exhibits an almost axial EPR spectrum, with g-values at 2.13 and 2.03, similar to those of soluble HIPIP proteins isolated from purple bacteria. It has a high reduction potential, of 260 mV at pH 7.5. Rhodothermus HIPIP is involved in the main membrane-bound electron-transfer pathway, being reduced by NADH or succinate only in the presence of cyanide. The possible physiological function of this novel HIPIP-type center is discussed.


Asunto(s)
Proteínas Bacterianas/metabolismo , Bacterias Aerobias Gramnegativas/metabolismo , Proteínas Hierro-Azufre/química , Proteínas Hierro-Azufre/metabolismo , Proteínas del Complejo del Centro de Reacción Fotosintética , Proteínas Bacterianas/aislamiento & purificación , Membrana Celular/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Calor , Proteínas Hierro-Azufre/aislamiento & purificación , Oxidación-Reducción , Consumo de Oxígeno
4.
Radiother Oncol ; 29(1): 45-50, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8295987

RESUMEN

Hemangioma is the most common benign neoplasm of the liver, for which a 'wait and see' policy has been advised when it is small or without symptoms. Surgery is the treatment of choice of these tumors when marked symptomatology is present. However, some of these lesions cannot be excised due to their size, multiplicity, location or medical conditions. In these patients, radiotherapy has been reported to give good results with minor morbidity, suspending the tumor growth and decreasing the symptomatology. Seven symptomatic patients were treated with radiotherapy with a dose of 15-30 Gray in 15-22 fractions. Improvement of the quality of life was observed in all patients and the regression of the tumor volume was confirmed by computed tomography in five, with a follow-up ranging from 40 to 67 months.


Asunto(s)
Hemangioma Cavernoso/radioterapia , Neoplasias Hepáticas/radioterapia , Adulto , Radioisótopos de Cobalto/uso terapéutico , Femenino , Estudios de Seguimiento , Hemangioma Cavernoso/epidemiología , Humanos , Neoplasias Hepáticas/epidemiología , Masculino , Persona de Mediana Edad , Teleterapia por Radioisótopo
5.
Res Microbiol ; 146(4): 315-24, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7569325

RESUMEN

The species Thermus scotoductus was recently described as containing several non-pigmented isolates from Selfoss, Iceland, and the X-1 strain from the USA (Kristjansson et al., 1994). In this study, we performed DNA:DNA hybridizations and chemotaxonomic studies on several non-pigmented Thermus isolates from other geographical areas to assess their relationship to the strains originally assigned to this species. The results of DNA:DNA hybridizations showed that strains NH and Dl from London and strains Vl-7a and Vl-13 from Vizela, Portugal, belonged to T. scotoductus. T. scotoductus X-1 (ATCC 27978) was composed of two stable colony types, one of which had a major glycolipid different from the one present in the other colony type and from all other Thermus strains examined as well. The fatty acid composition of the isolates from Selfoss and London were practically identical. However, the fatty acid composition of strain X-1, the individual colony types of this strain and the Vizela strains were different from the Selfoss-London isolates and from each other. Another non-pigmented strain, designated SPS-11, belonged to a different DNA homology group.


Asunto(s)
ADN Bacteriano/análisis , Ácidos Grasos/química , Thermus/clasificación , Cromatografía en Capa Delgada , ADN Bacteriano/química , Técnicas In Vitro , Lípidos/química , Hibridación de Ácido Nucleico , Thermus/química , Thermus/genética
6.
J Hosp Infect ; 15(3): 255-63, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1971632

RESUMEN

The humidification trays of five of seven incubators in a neonatology unit of a hospital were found to be colonized with Legionella pneumophila, serogroup 1. Bacteriological analysis of the water in the humidification trays showed very large numbers of heterotrophic bacteria, one of which also contained Pseudomonas aeruginosa. Two hot water systems supply the neonatology unit, either of which is used to add water to the humidification trays; one system (A) is maintained at about 60 degrees C, while the other system (B) is maintained at 45 degrees C. The latter was also found to be colonized with L. pneumophila, Sg1. Monoclonal antibody (Mab) subgrouping of the isolates, indicated that system B was the source of colonization of the humidification trays of the incubators.


Asunto(s)
Incubadoras para Lactantes , Legionella/aislamiento & purificación , Microbiología del Agua , Anticuerpos Monoclonales , Contaminación de Equipos , Humanos , Humedad , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Legionella/clasificación , Legionella/crecimiento & desarrollo , Portugal , Serotipificación
7.
Adv Exp Med Biol ; 238: 47-58, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3250247

RESUMEN

Membranes from a thermophilic eubacterium, Thermus sp. strain SPS 11, isolated from thermal springs of São Pedro do Sul spa (Portugal), are characterized for having two main polar lipids, a glycolipid (GL) with four monosaccharide residues, which at 73 degrees C accounts for 95% of the carbohydrate in the total lipid extracts, and a glycophospholipid (PL) which at 73 degrees C accounts for about 90% of the lipid phosphorous. A complex mixture of carotenoids (CA) makes up 11% by weight of the total membrane lipids. The branched fatty acyl chains (iso C15 and iso C17) comprise about 90% of the alifatic moieties of the polar lipids of this bacterium. Moreover, when the growth temperature increases from 50 to 73 degrees C there is an increase of the iso C17/ iso C15 ratio and of the GL/PL ratio. We have studied the biophysical properties of bilayers (as multilamellar liposomes) prepared from GL, PL and the mixtures of PL, GL and CA in proportions found in the membranes of bacteria growing at their optimal growth temperature, using polarization of DPH fluorescence, low and wide-angle X-ray diffraction and differential scanning calorimetry. The three techniques agree in showing the presence of a broad phase transition from a gel (L beta) phase to a liquid-crystal (L alpha) phase between 8 and 30 degrees C, for all the lipid dispersions studied except for the GL. Although all the dispersions studied form a bilayer structure at all the temperatures studied, only the mixture of the three components (PL, GL + CA) avoids the phase separation present in the mixtures of PL + CA at temperatures lower than 30 degrees C and PL + GL at temperatures lower than 55 degrees C. Our results are compared with those of Pinheiro et al. (1978) obtained with the 31p-NMR technique and applied to the study of the same samples.


Asunto(s)
Lípidos de la Membrana/aislamiento & purificación , Thermus/análisis , Rastreo Diferencial de Calorimetría , Fenómenos Químicos , Química Física , Polarización de Fluorescencia , Membrana Dobles de Lípidos , Liposomas , Temperatura , Difracción de Rayos X
8.
Int Surg ; 86(3): 158-61, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11996072

RESUMEN

There are a few prospective studies assessing the severity of acute pancreatitis with exclusive criteria for biliary etiology. In a cohort prospective study, Ranson (biliary etiology), Glasgow-modified, APACHE-II, and APACHE-O prognostic criteria were assessed in 65 patients with acute biliary pancreatitis (ABP). Local complications such as necrosis with fluid peripancreatic collection (3 patients), fluid collection with pancreas enlargement (3 patients), pancreatic fistula (1 patients), and pancreatic pseudocyst (1 patients); and organic failure such as renal (5 patients), hemodynamic (3 patients), and respiratory (3 patients) were found. The prognostic criteria performance, according to parameter number or positive variables evidenced that relative risk (RR) varied from 4.7 to 11.2, sensibility from 33.3% to 83.3%, specificity from 79.2% to 98.1%, positive predictive value from 45.0% to 83.3%, negative predictive value from 86.4% to 95.5%, and accuracy from 78.5% to 89.6%. In isolation, most important parameters correlated to severity included white blood cell count >18,000/mm3, lactate dehydrogenase (LDH) >400 UI/l, 10% drop of the hematocrit, serum calcium <8 mg/dl, increase of urea nitrogen >2 mg/dl, aspartate aminotransferase (AST) >200 mg/dl, LDH >600 UI/l, white blood cell count >15,000/mm3, urea >45 mg/dl, arterial pH < or = 7.33 or > or = 7.49, creatinin < or = 0.6 or > or = 1.4, hematocrit < or = 30 or > or = 45.9, white blood cell count < or = 3,000/mm3 or > or = 14,900/mm3. Ranson, Glasgow-modified, APACHE-II, and APACHE-O acute biliary pancreatitis severity criteria all present good sensibility and excellent specificity.


Asunto(s)
Colelitiasis/complicaciones , Pancreatitis/clasificación , Índice de Severidad de la Enfermedad , APACHE , Dolor Abdominal/etiología , Enfermedad Aguda , Aspartato Aminotransferasas/sangre , Calcio/sangre , Humanos , L-Lactato Deshidrogenasa/sangre , Recuento de Leucocitos , Pancreatitis/sangre , Pancreatitis/etiología , Pronóstico , Estudios Prospectivos , Sensibilidad y Especificidad
9.
Acta Med Port ; 2(3): 147-53, 1989.
Artículo en Portugués | MEDLINE | ID: mdl-2560319

RESUMEN

In the management of the unresectable cavernous hemangioma of the liver, the Radiotherapy has an important role. This paper reports the experience of Radiotherapy department of Hospital Santa Maria. The authors review retrospectively the literature concerning techniques, results and complications of this therapy and analyse other possible attitudes in treatment of these lesions.


Asunto(s)
Carcinoma Hepatocelular/radioterapia , Hemangioma Cavernoso/radioterapia , Neoplasias Hepáticas/radioterapia , Adulto , Carcinoma Hepatocelular/diagnóstico por imagen , Niño , Estudios de Evaluación como Asunto , Femenino , Hemangioma Cavernoso/diagnóstico por imagen , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
10.
Stand Genomic Sci ; 9(3): 1062-75, 2014 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25197483

RESUMEN

Rubrobacter radiotolerans strain RSPS-4 is a slightly thermophilic member of the phylum "Actinobacteria" isolated from a hot spring in São Pedro do Sul, Portugal. This aerobic and halotolerant bacterium is also extremely resistant to gamma and UV radiation, which are the main reasons for the interest in sequencing its genome. Here, we present the complete genome sequence of strain RSPS-4 as well as its assembly and annotation. We also compare the gene sequence of this organism with that of the type strain of the species R. radiotolerans isolated from a hot spring in Japan. The genome of strain RSPS-4 comprises one circular chromosome of 2,875,491 bp with a G+C content of 66.91%, and 3 circular plasmids of 190,889 bp, 149,806 bp and 51,047 bp, harboring 3,214 predicted protein coding genes, 46 tRNA genes and a single rRNA operon.

12.
Appl Microbiol Biotechnol ; 75(5): 1039-45, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17361428

RESUMEN

A production process, using upshock fermentation and osmotic downshock, for the effective production/excretion of mannosylglycerate (MG) by the trehalose-deficient mutant of the strain Thermus thermophilus RQ-1 has been developed. In the first phase of fed-batch fermentation, the knockout mutant was grown at 70 degrees C on a NaCl-free medium. After the culture reached the end of the exponential growth phase, upshift in temperature and NaCl concentration was applied. The temperature was increased to 77 degrees C, and NaCl was added up to 3.0% and kept constant during the second phase of fermentation. Although this shift in cultivation parameters caused a dramatic drop of cell density, a significant improvement in accumulation of MG up to 0.64 micromol/mg protein compared to batch fermentations (0.31 micromol/mg protein) was achieved. A total yield of 4.6 g MG/l of fermentation broth was obtained in the dialysis bioreactor with a productivity of 0.29 g MG l(-1) h(-1). The solute was released from the harvested biomass by osmotic downshock using demineralized water at 70 degrees C. More than 90% of the intracellularly accumulated solute was recovered from the water fraction. The process was very efficient, as hyperosmotic shock, release of the solute, and reiterative fed-batch fermentation could be repeated at least four times.


Asunto(s)
Fermentación/fisiología , Manosa/análogos & derivados , Thermus thermophilus/genética , Thermus thermophilus/metabolismo , Trehalosa/deficiencia , Ácidos Glicéricos , Manosa/biosíntesis , Presión Osmótica
13.
J Bacteriol ; 182(16): 4632-6, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10913099

RESUMEN

The operation of a novel glycolytic pathway was demonstrated in nongrowing cells of Thermococcus zilligii by analysis of the isotopic enrichment in the end products derived from fermentation of (13)C-labeled glucose. The new pathway involved the formation of formate, derived from C-1 in glucose, via cleavage of a six-carbon carboxylic acid.


Asunto(s)
Glucosa/metabolismo , Glucólisis , Thermococcus/metabolismo , Isótopos de Carbono , Fermentación , Hexoquinasa/metabolismo , Marcaje Isotópico , Espectroscopía de Resonancia Magnética , Fosfofructoquinasa-1/metabolismo , Thermococcus/crecimiento & desarrollo
14.
Int J Syst Bacteriol ; 45(4): 633-9, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7547281

RESUMEN

Strains of Thermus silvanus sp. nov. and strains of Thermus chliarophilus sp. nov. were isolated from the hot spring at Vizela in northern Portugal and the hot spring at Alcafache in central Portugal, respectively. The strains of T. silvanus produce orange-red-pigmented colonies and have an optimum growth temperature of about 55 degrees C, while the strains of T. chliarophilus produce yellow-pigmented colonies and have an optimum growth temperature of about 50 degrees C. The strains of both species are catalase negative. These species can be distinguished from each other and from Thermus ruber by biochemical characteristics, fatty acid composition data, and 16S rRNA gene sequence data. Our phylogenetic analysis showed that strains VI-R2T (T = type strain) and ALT-8T belong to the T. ruber line of descent. The type strain of T. silvanus is strain VI-R2 (= DSM 9946), and the type strain of T. chliarophilus is strain ALT-8 (= DSM 9957).


Asunto(s)
Thermus/clasificación , Secuencia de Bases , ADN Ribosómico/química , Ácidos Grasos/análisis , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Thermus/genética , Thermus/crecimiento & desarrollo
15.
Arch Microbiol ; 126(1): 57-64, 1980 May.
Artículo en Inglés | MEDLINE | ID: mdl-6772136

RESUMEN

The temporal depletion and accumulation of polyols were investigated in the fungus Geotrichum cnadidum. The major intracellular polyols were tentatively identified by paper chromatography as mannitol and arabitol. Inositol was also present in small quantities, and trehalose was also detected in appreciable concentrations. Germination and vegetative growth depended on the type and concentration of the sole exogenous carbon source. Mannitol occurred in arthrospores at 9.4% of the dry weight after several days growth in 2% (w/v) glucose solid medium, and became depleted during germination and vegetative growth in liquid medium containing 2% (w/v) glucose, 2% (w/v) sodium acetate or 25% (w/v) glucose as sole carbon source. This hexitol latter accumulated during arthrosporulation. The depletion and accumulation of ethanol-soluble carbohydrate believed to be primarily trehalose was temporally similar to that of mannitol. Arabitol accumulated intracellularly during germination and vegetative growth in sodium acetate medium and 25% glucose medium. This pentitol was not detected intracellularly at any culture age during growth in 2% glucose medium. Prolonged incubation of the culture in 25% glucose medium after stationary phase was reached resulted in the gradual disappearance of arabitol from the arthrospores simultaneously with an increase in intracellular mannitol. In comparison, ethanol-soluble carbohydrate did not change with prolonged incubation in this medium.


Asunto(s)
Geotrichum/metabolismo , Manitol/metabolismo , Hongos Mitospóricos/metabolismo , Alcoholes del Azúcar/metabolismo , Arabinosa/análogos & derivados , Arabinosa/metabolismo , Metabolismo de los Hidratos de Carbono , Geotrichum/crecimiento & desarrollo , Cinética , Esporas Fúngicas/metabolismo , Trehalosa/metabolismo
16.
Adv Biochem Eng Biotechnol ; 61: 117-53, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9670799

RESUMEN

The accumulation of compatible solutes is a prerequisite for the adaptation of microorganisms to osmotic stress imposed by salt or organic solutes. Two types of strategies exist to cope with high external solute concentrations; one strategy is found in the extremely halophilic Archaea of the family Halobacteriaceae and the Bacteria of the order Haloanaerobiales involving the accumulation of inorganic ions. The other strategy of osmoadaptation involves the accumulation of specific organic solutes and is found in the vast majority of microorganisms. The organic osmolytes range from sugars, polyols, amino acids and their respective derivatives, ectoines and betaines. The diversity of these organic solutes has increased in the past few years as more organisms, especially thermophilic and hyperthermophilic Bacteria and Archaea, have been examined. The term compatible solute can also be applied to solutes that protect macromolecules and cells against stresses such as high temperature, desiccation and freezing. The mechanisms by which compatible solutes protect enzymes, cell components and cells are still a long way from being thoroughly elucidated, but there is a growing interest in the utilization of these solutes to protect macromolecules and cells from heating, freezing and desiccation.


Asunto(s)
Archaea/metabolismo , Bacterias/metabolismo , Fenómenos Fisiológicos Bacterianos , Temperatura , Microbiología del Agua , Archaea/química , Bacterias/química , Carbohidratos/química , Euryarchaeota/metabolismo , Glutamatos/química , Concentración Osmolar , Potasio/química
17.
J Appl Bacteriol ; 69(5): 750-7, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2276989

RESUMEN

The heterotrophic bacterial population of a bottled mineral water stored in returnable glass bottles and in polyvinyl chloride (PVC) bottles at room temperature was studied over 9-12 months. The plate counts in R2A medium incubated at 22 degrees and 37 degrees C were low initially, increasing to 10(4)-10(5) cfu/ml within a few days of bottling. The number of bacteria recovered at 22 degrees C from PVC bottles was fairly constant during the storage period, but the population isolated at 37 degrees C decreased markedly after storage for 1 year. The major components of the population were Pseudomonas strains, one of which was identified as Pseudomonas vesicularis. Major changes took place during storage; two groups of bacteria (B and C) were dominant initially, but during the latter period of storage other groups (F, G and H) increased in number.


Asunto(s)
Bacterias/crecimiento & desarrollo , Microbiología de Alimentos , Conservación de Alimentos , Aguas Minerales , Microbiología del Agua , Recuento de Colonia Microbiana , Vidrio , Fenotipo , Cloruro de Polivinilo
18.
Int J Syst Evol Microbiol ; 50 Pt 4: 1457-1461, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10939650

RESUMEN

DNA-DNA reassociation studies, 16S rRNA gene sequence comparisons and fatty acid analysis were used to reassess the taxonomic status of the type strain of Rhodothermus obamensis and several strains of the genus Rhodothermus isolated from widely distributed shallow marine hot springs. The results show that the type strain of R. obamensis, JCM 9785T, has a DNA-DNA reassociation value of 78% with the type strain of R. marinus, DSM 4252T. The other strains examined had DNA-DNA reassociation values that varied between about 68 and 94% with R. marinus. The 165 rRNA gene sequence was determined for the type strain of R. obamensis and found to share 99.5% similarity with the type strain of R. marinus. The fatty acid composition of R. obamensis was slightly different from that of the other strains examined, but indicated that this strain is very closely related to the other strains examined in this study. On the basis of DNA-DNA reassociation values, 16S rRNA gene sequence comparison and fatty acid profiles, it was concluded that R. obamensis and R. marinus represent the same species and that the name Rhodothermus obamensis should be regarded as a junior synonym of Rhodothermus marinus.


Asunto(s)
Bacterias Aerobias Gramnegativas/clasificación , Microbiología del Agua , Clonación Molecular , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácidos Grasos/análisis , Bacterias Aerobias Gramnegativas/química , Bacterias Aerobias Gramnegativas/genética , ARN Bacteriano/análisis , ARN Ribosómico 16S/análisis , Temperatura
19.
Antonie Van Leeuwenhoek ; 66(4): 357-63, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7710285

RESUMEN

The polar lipids and fatty acid composition of Thermus aquaticus YT-1 and YS 041, T. filiformis Wai33 A1 and eighteen isolates from New Zealand, several of which are attributed to T. filiformis, were compared to complement the taxonomy of these organisms. The polar lipid patterns were essentially similar in all strains and consisted of one major phospholipid and one major glycolipid. The fatty acid analysis produced three basic groups corresponding to T. filiformis Wai33 A1, T. aquaticus and the third to the other New Zealand strains. The presence of hydroxy fatty acids is reported in Thermus spp. for the first time.


Asunto(s)
Ácidos Grasos/análisis , Lípidos/análisis , Thermus/química , Glucolípidos/análisis , Nueva Zelanda , Fosfolípidos/análisis , Filogenia , Thermus/clasificación
20.
Appl Environ Microbiol ; 61(6): 2351-7, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16535053

RESUMEN

(sup13)C nuclear magnetic resonance spectroscopy and (sup1)H nuclear magnetic resonance spectroscopy were used to identify and quantify the organic solutes of several strains of halophilic or halotolerant thermophilic bacteria. Two strains of Rhodothermus marinus and four strains of "Thermus thermophilus" grown in complex medium containing NaCl were examined. 2-O-Mannosylglycerate was a major compatible solute in all strains: the Thermus strains accumulated the (beta)-anomer only, whereas both anomers were found in R. marinus. 2-O-(beta)-mannosylglycerate and 2-O-(alpha)-mannosylglycerate were the major compatible solutes in R. marinus. The former was the predominant solute in cells grown in 2.0 and 4.0% NaCl-containing medium, while the latter was the predominant compatible solute at higher salinities. Glutamate, trehalose, and glucose were also present as minor components. The intracellular K(sup+) concentration, as determined by (sup39)K nuclear magnetic resonance spectroscopy, in R. marinus increased with salinity and was sufficient to balance the negative charges of the mannosylglycerate. In addition to 2-O-(beta)-mannosylglycerate, trehalose was a major compatible solute of "T. thermophilus." 2-O-(beta)-Mannosylglycerate was the main solute in medium containing 1.0 or 2.0% NaCl, while trehalose predominated in cells grown in medium supplemented with 3.0 or 4.0% NaCl. Glycine betaine, in lower concentrations, was also detected in two "T. thermophilus" strains. This is the first report of mannosylglycerate as a compatible solute in bacteria.

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