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At least 19 recordsLinked to original sources
PubMed1977

Fiberoptic bronchoscopy and culture bacteria from the lower respiratory.

Forty-five specimens were obtained by sequential translaryngeal aspiration and fiberoptic bronchoscopy from 31 clinically unifected patients with lung cancer in order to evaluate the reliability of routine fiberoptic bronchoscopy for culture of the lower respiratory tract. Bacteria were recovered brom 98 percent (44) of the specimens obtained via fiberoptic bronchoscopy and from 58 percent (26) of the specimens obtained by the preceding translaryngeal aspiration. The microorganisms grown from cultures of specimens obtained by fiberoptic bronchoscopy consisted of mixtures of both nonpathogenic and potenitally pathogenic bacteria. Potentially pathogenic bacteria were present in 87 percent (39) of the specimens from fiberoptic bronchoscopy and 31 percent (14) of specimens from translayngeal aspiration. The results of cultures from the two procedures agreed completely in only a single instance. Culture of washings or secretions obtained by routine fiberoptic bronchoscopy is not recommended because it provides inaccurate and clinically confusing information about the presence or types of bacteria in the lower respiratory tract prior to instrumentation.

Aged↗
PubMedDate not supplied

[Intestinal autoflora of the test subjects in a 6-month biological engineering experiment].

During a 6-month bioengineering experiment the intestinal microflora of four test subjects was examined. Changes in the composition of different groups of intestinal microflora (bifidobacteria, lactic-acid bacteria, sporogenous anaerobes, proteus, etc) were found. In spite of the unstable pattern of the intestinal microflora and its tendency for simplification, the total number of microorganisms in 1 g of feces remained relatively unchanged in all the test subjects.

Biomedical Engineering↗
PubMed1975

Phospholipase D activity of gram-negative bacteria.

A phospholipase hydrolyzing cardiolipin to phosphatidic acid and phosphatidyl glycerol was characterized in gram-negative bacteria but was absent in preparations of gram-positive bacteria, Saccharomyces cerevisiae, and rat liver mitochondria. In cell-free extracts of Escherichia coli, Salmonella typhimurium, Proteus vulgaris, and Pseudomonase aeruginosa, this cardiolipin-hydrolyzing enzyme had similar pH and Mg2+ requirements and displayed a specificity which excluded phosphatidyl glycerol and phosphatidyl ethanolamine as substrates.

Animals↗
PubMedDate not supplied

[Mechanism of the oxidation of divalent iron and manganese by iron bacteria developing in a neutral acidic medium].

The paper confirms the existence of a peroxide mechanism involved in oxidation of iron and manganeses by the most typical iron bacteria growing at neutral acidity of the medium. Oxidation of bivalent iron and manganese is accomplished by the simultaneous action of catalase and hydrogen peroxide produced in the respiratory chain in the course of oxidation of organic substances. Catalase performs the peroxidase function in these processes. The possibility of these biological reactions to occur and the necessary conditions have been studied in vitro. Possible variants of iron and manganese oxidation by iron bacteria are discussed, including the conditions for "symbiotic" oxidation of manganese by mixed cultures of microorganisms.

Arthrobacter↗
PubMed1976

Purification and some properties of NADP+ -specific isocitrate dehydrogenase from an extreme thermophile, Thermus flavus AT-62.

Thermostable NADP+ -specific isocitrate dehydrogenase (EC 1.1.1.42) was purified from crude extract of an extremely thermophilic bacterium Thermus flavus AT-62 through DEAE-cellulose column, acetone fractionation, DEAE-Sephadex A-50 column and isoelectric focussing. The enzyme was purified about 500-folds in its specific activity and purity was found to be about 96%. The enzyme was not inactivated after 60 min at 70 degrees C, but 20 and 80% of the activity were lost after 60 min at 80 degrees and 90 degrees C, respectively. Oxalacetate plus glyoxylate (each 1 nM) demonstrated 75% inhibition of the activity in concerted manner. The degree of the inhibition and the affinity of the enzyme for isocitrate and NADP+ decreased with the rise of temperature, especially above 60 degrees C. The activation energy below and above 60 degrees C were 14,500 and 8,000 cal per mole respectively. In CD spectra negative bands at 210 and 220nm were observed and alpha-helix content was calculated to be about 26%. In the course of heating up to 60 degrees practically no change in CD bands are observed, but above 60 degrees the depth of CD bands decreased gradually and remarkably above 80 degrees C. The effect of temperature on kinetic parameters and secondary structures of the enzyme was discussed in relation to the temperature adaptation of the organism.

Circular Dichroism↗
PubMed1976

Enzymatic synthesis of oligonucleotides of defined sequence. The "single addition" of 2(3)-O-dihydrocinnamoyl-nucleoside 5'-diphosphate to a primer oligonucleotide catalyzed by a thermophilic polynucleotide phosphorylase.

Several oligonucleotides of defined sequence were synthesized using 2'(3')-O-dihydrocinnamoyl-nucleoside 5'-diphosphates (DHC-NDP) as substrates for polynucleotide phosphorylase [EC 2.7.7.8] from Thermus thermophilus. The enzyme catalyzed the transfer of one nucleotidyl residue from each of the 2'(3')-O-dihydrocinnamoyl esters of CDP, UDP, and GDP to the 3'-terminus of the primer triadenosine diphosphate, (Ap)2A. The products were shown to be (Ap)3C, (Ap)3U, and (Ap)3G by enzymatic analysis.

Adenine Nucleotides↗
PubMed1976

Purification and properties of D-glyceraldehyde-3-phosphate dehydrogenase from an extreme thermophile, Thermus thermophilus strain HB 8.

1. D-Glyceraldehyde-3-phosphate dehydrogenase from an extreme thermophile, T. thermophilus strain HB8, was purified and crystallized. 2. The enzyme was found to possess remarkable heat stability, being slowly inactivated at 90 degrees C. 3. Basic kinetic constants and pH profile are reported. The enzyme was activated 25-fold by 90 mM NH4Cl, and also by ethanol up to 5-fold at 30 degrees C. 4. The enzyme was found to be far more resistant to urea or sodium dodecylsulfate than the rabbit enzyme. 5. The enzyme was shown to be a tetramer of molecular weight 130000--135000. Amino acid composition analysis revealed no unusual features. Circular dichroic spectra suggested that the contents of the ordered structure of the thermophile enzyme are similar to those of the rabbit enzyme. 6. The other catalytic properties of the thermophile enzyme are discussed in comparison with those of the enzymes from other sources.

Alcohols↗
PubMed1977

Superoxide dismutase from Thermus aquaticus. Isolation and characterisation of manganese and apo enzymes.

Superoxide dismutase has been isolated and characterised from the extreme thermophile Thermus aquaticus. The pure enzyme is a reddish-purple manganese-containing protein with a molecular weight of approximately 80000 +/- 5000. Combination of gel electrophoresis in dodecylsulphate and amino acid analysis shows that it is composed of four identical subunit polypeptide chains consisting of approximately 186 amino acids. The tetrameric protein contains two atoms of manganese. A stable manganese-free apoprotein has been prepared by treatment with EDTA in 8 M urea at acidic pH. The apoprotein regains the tetrameric structure in the absence of manganese but is inactive. Reconstitution of active Mn-enzyme was achieved byaddition of Mm2+ apoprotein in 8 M urea at acid pH. Reconstitution was monitored by absorption spectroscopy, manganese analysis and regain of activity and by these criteria the reconstituted enyzme with two atoms Mn per mole is indistinguishable from the native enzyme. The enhanced stability of the thermophile apoenzyme and Mn-enzyme is of advantage for studies of the structure and mechanism of action of superoxide dismutase. The N-terminal amino acid sequence to the 40th residue of the submit was determined by automated Edman degradation. The sequence has a close resemblance to that of the dimeric Mn-enzyme from another thermophile, Bacillus stearothermophilus.

Amino Acid Sequence↗
PubMed1977

Repressible alkaline phosphatase from Thermus aquaticus: associated phosphodiesterase activity.

A repressible alkaline phosphatase has been isolated from the extreme bacterial thermophile. Thermus aquaticus, and has been purified to homogeneity as judged by disc acrylamide electrophoresis and sodium dodecyl sulfate electrophoresis. Upon investigation, the purified enzyme was shown to hydrolyze certain phosphodiesters in addition to a wide variety of phosphomonoesters. The diesters included bis-p-nitro-phenyl phosphate and thymidine 3'-monophospho-p-nitro-phenyl ester. The temperature optimum for the diesterase activity was 80--85 degrees at pH 7.2. Orthophosphate competitively inhibited both activities. Nucleotides such as AMP, ADP, and ATP also inhibited both esterase activities as did alpha-D-glucose 1-phosphate and alpha-sodium glycerol phosphate. The isoelectric point of the enzyme was determined to be 8.4.

Adenine Nucleotides↗
PubMed1976

Purification and characterization of a repressible alkaline phosphatase from Thermus aquaticus.

A repressible alkaline phosphatase has been isolated from the extreme bacterial thermophile, Thermus aquaticus. The enzyme can be derepressed more than 1,000-fold by starving the cells for phosphate. In derepressed cells, nearly 6% of the total protein in a cell-free enzyme preparation is alkaline phosphatase. The enzyme was purified to homogeneity as judged by disc acrylamide electrophoresis and sodium dodecyl sulfate electrophoresis. By sucrose gradient centrifugation it was established that the enzyme has an approximate molecular weight of 143,000 and consists of three subunits, each with a molecular weight of 51,000. Tris buffer stimulates the activity of the enzyme, which has a pH optimum of 9.2. The enzyme has a broad temperature range with an optimum of 75-80 degrees. The enzyme catalyzes the hydrolysis of a wide variety of phosphorylated compounds as do many of the mesophilic alkaline phosphatases. The Michaelis constant(Km) for the enzyme is 8.0 X 10(-4) M. Amino acid analysis of the protein revealed little in the amino acid composition to separate it from other mesophilic enzymes which have been previously studied.

Alkaline Phosphatase↗
PubMed1976

Characterization of a nitrogen-fixing bacterial strain from the roots of Digitaria sanguinalis.

Rates of nitrogen fixation of 3 to 10 g of N2 fixed per hectare per day were associated with root systems of Digitaria sanguinalis. A Gram-negative motile aerobic bacterial strain that was capable of N2 fixation was isolated from a washed root sample of one of these plants. Optimal growth and N2 fixation occurred at a pH of about 6.5, a temperature of 30-37 degrees C, and at a pO2 of about 0.01 atm. Increased rates of N2 fixation resulted when this strain was grown in mixed cultures with aerobic or facultative bacteria. Observations of cellular and cultural morphology and results of biochemical and physiological studies indicate that the isolate may be related to the Azotobacteraceae but that it is not identical with any of the members of this family. The importance of N2 fixation by this isolate in nature is unknown.

Acetylene↗
PubMed1976

Thermothrix thioparus gen. et sp. nov. a facultatively anaerobic facultative chemolithotroph living at neutral pH and high temperature.

Thermothrix thioparus gen. et ep. nov. occurs naturally in a New Mexico hot spring at a temperature of 74 degrees C, a pH of 7.0, and a HS- concentration of 1 mg/litre. The organism is gram-negative, non-motile, 0.5-1.0 X 3-20 mum, and forms cell chains up to 1 cm in length. The resulting filaments do not possess a sheath. Sulfur is deposited extracellularly. The organism was isolated using an autotrophic medium with HS- as the energy source and NO3- as the terminal electron acceptor. Anaerobically either NO2- or NO3- is required, NO2- is formed from NO3-, and no observable gas is evolved. Oxygen can also be used as the terminal electron acceptor, but growth is poor because of the decreased solubility of O2 at temperatures required for growth. Alternate energy sources used aerobically and anaerobically include hexose, HS-, SO3-, and S2O3=. The temperature optimum is 70-73 degrees C and growth occurs from 62 to 77 degrees C. The organism's thermal and physiological characteristics are compared to those of Bacillus stearothermophilus, Methanobacterium thermoautotrophicum, Sulfolobus acidocalderius, Thermus aquaticus, Thermus flavus, as well as Thiobacillus denitrificans, the latter being the only other facultatively anaerobic chemolithotroph which has been isolated and described.

Aerobiosis↗
PubMed2026

Genomic and polyphasic characterization of six novel Hymenobacter species isolated from soil in Korea.

Six bacterial strains (BT523T, BT559T, 15J16-1T3BT, BT730T, DG25AT, and DG25BT) were isolated from soil samples in Korea and assigned to the family Hymenobacteraceae (order Cytophagales, class Cytophagia). Phylogenetic analysis based on 16S rRNA gene sequences showed that the strains formed distinct lineages within the genus Hymenobacter. Strains BT523T, BT559T, and 15J16-1T3BT exhibited highest sequence similarities to Hymenobacter armeniacus BT189T (97.6%), Hymenobacter polaris RP-2-7 T (97.8%), and Hymenobacter paludis KBP-30 T (98.3%), respectively, while strains BT730T, DG25AT, and DG25BT were most closely related to Hymenobacter tibetensis XTM003T, with similarities of 96.3-96.6%. All strains were Gram-negative, aerobic, rod-shaped, and formed red to pink pigmented colonies. Whole-genome analysis revealed genome sizes ranging from 3.78 to 6.33 Mb with G + C contents of 55.5-65.0%. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the strains and their closest relatives were below the accepted thresholds for species delineation, supporting their classification as novel species. Functional annotation indicated the presence of genes associated with core metabolism, stress response, and pigment biosynthesis, reflecting adaptation to soil environments. Secondary metabolite analysis further revealed the presence of biosynthetic gene clusters, including terpene and siderophore pathways. Based on polyphasic taxonomic evidence, the six strains are proposed to represent six novel species of the genus Hymenobacter, for which the names Hymenobacter miniatus sp. nov., Hymenobacter madidus sp. nov., Hymenobacter convexus sp. nov., Hymenobacter rubellus sp. nov., Hymenobacter erythromyxa sp. nov., and Hymenobacter radioresistens sp. nov. are proposed. The type strains are BT523T (= KCTC 72341 T = NBRC 114851 T), BT559T (= KACC 21821 T = NBRC 114852 T), 15J16-1T3BT (= KCTC 42995 T = NBRC 112818 T), BT730T (= KACC 22457 T = NBRC 116482 T), DG25AT (= KCTC 32451 T = TBRC 19856 T), and DG25BT (= KCTC 32452 T = JCM 19444 T).

Soil Microbiology↗
PubMedDate not supplied

[Quantitative study and typization of aerobic bacteria in the conjunctival sacs of healthy eyes].

We carried out a qualitative and quantitative bacteriological research into the conjunctives of 220 subjects in good health mostly women (180) exempt from recent or previous eyes diseases. In order to gather conjunctival bacteria we employed with a few variations Hadley's et al. (1973 [12]) method. Among the calculated bacterial flora we found as the most numerous ones Staphylococcus epidermidis (mean valor 1960/ml), then Streptococci (480/ml), Micrococci (465/ml), Diphteroides (360/ml), Enterococci (77/ml) and numerous (700/ml) Gram-positives Cocci like Sarcina, Micrococcus tetragenes, Diplococcus, and very rarely bacterial genera Gram-negatives or Iphomycetes, also numerically inferior as regards the researches of other Authors, because owen study is carried by into eyes exempt from diseases.

Adolescent↗