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1.
Deoxyribonucleic Acid Homology Among the Fruiting Myxobacteria   总被引:1,自引:0,他引:1       下载免费PDF全文
Deoxyribonucleic acid similarities were determined by competition experiments. The several strains of fruiting myxobacteria tested showed from 23 to 89% homology with the reference strains Myxococcus xanthus (FB) and M. fulvus (M6).  相似文献   

2.
In two series of rats, the concentration of carnitine in plasma was 39.9 and 37.8 μmol/ liter, in skeletal muscle tissue 2.97 and 3.26 μmol/g dry wt and the urinary excretion 3.2 and 2.4 μmol/24 h. The renal clearance of carnitine was calculated to 88 and 76 ml/24 h. L-[Me-14C]Carnitine and DL-[Me-14C]carnitine have been administered to rats. Only labeled l-carnitine has been found on chromatographic analysis of plasma, urine, and muscle tissue. The specific radioactivity of carnitine in plasma, urine, and muscle tissue has been followed for up to 16 days. A two-compartment metabolic model has been used to interpret the result of the experiment with labeled l-carnitine and the rate constants and compartment sizes have been calculated. The total body content of carnitine was 57 μmol (about 35 μmol/100 g body wt) and the daily turnover was about 7% of the body pool. The daily synthesis of carnitine in the rat is estimated to about 2 μmol/100 g body wt.  相似文献   

3.
Myxococcus coralloides ATCC 25202 and Myxococcus fulvus ATCC 23093 produced an extracellular diffusible factor during fruiting body formation. This factor acted to shorten the lag time before the appearance of aggregates and to increase the number of aggregates for both species. The factor from M. coralloides presented a more selective activity on the aggregation of this species.  相似文献   

4.
Prenylated quinones, especially menaquinones, have significant physiological activities, but are arduous to synthesize efficiently. Due to the relaxed aromatic substrate specificity and prenylation regiospecificity at the ortho- site of the phenolic hydroxyl group, the aromatic prenyltransferase NovQ from Streptomyces may be useful in menaquinone synthesis from menadione. In this study, NovQ was overexpressed in Pichia pastoris. After fermentation optimization, NovQ production increased by 1617%. Then the different effects of metal ions, detergents and pH on the activity of purified NovQ were investigated to optimize the prenylation reaction. Finally, purified NovQ and cells containing NovQ were used for menadione prenylation in vitro and in vivo, respectively. Menaquinone-1 (MK-1) was detected as the only product in vitro with γ,γ-dimethylallyl pyrophosphate and menadione hydroquinol substrates. MK-3 at a concentration of 90.53 mg/L was detected as the major product of whole cell catalysis with 3-methyl-2-buten-1-ol and menadione hydroquinol substrates. This study realized whole cell catalysis converting menadione to menaquinones.  相似文献   

5.
Microbial community dynamics in a flowerpot-using solid biowaste composting (FUSBIC) process were monitored seasonally by quinone profiling and conventional microbiological methods. The FUSBIC system, which consisted of three flowerpots (14 L or 20 L capacity) with 5-6 kg each of a soil-compost mixture (SCM) as the primary reactors, was loaded daily with household biowaste from November 1998 to October 1999. The monthly average waste reduction rate was 88.2% for the 14-L system and 92.5% for the 20-L system on a wet weight basis. The direct total microbial count detected in the 14-L primary reactors ranged from 4.5 to 9.6x10(11) cells.g(-1) of dry wt of SCM, and the viable count of aerobic heterotrophic bacteria recovered on agar plates at 28 degrees C varied from 1.9 to 5.7x10(11) CFU.g(-1) of dry wt. The quinone content of SCM samples from the 14-L and 20-L systems ranged from 160 to 353 nmol.g(-1) of dry SCM. Ubiquinones, unsaturated menaquinones, and partially saturated menaquinones constituted 15.0-36.4, 14.8-22.0, and 41.8-61.6 mol% of the total content, respectively. The major quinone types detected were usually MK-8(H(2)), MK-9(H(2)), and Q-10. Variations in quinone profiles were evaluated numerically by using two parameters, the dissimilarity index (D) and microbial divergence index (MD(q)). The upper limit of seasonal changes in the microbial community structure was about 30% as expressed by D values. The MD(q) values calculated ranged from 18 to 22. A significant positive correlation was found between seasonal temperature and bacterial populations containing partially saturated menaquinones. These results indicated that the FUSBIC system contained highly diverse microbial populations that fluctuated to some extent depending on seasonal temperature. Members of the Actinobacteria were suggested to be the major constituents of the total population present.  相似文献   

6.
The effect of aqueous extracts of carob (Ceratonia siliqua) pods, gallotannic acid, gallic acid, and catechol on several microorganisms was studied. Carob pod extract and tannic acid showed a strong antimicrobial activity toward some cellulolytic bacteria. On the basis of tannin content, to which antimicrobial effect was related, carob pod extracts inhibited Cellvibrio fulvus and Clostridium cellulosolvens at 15 μg/ml, Sporocytophaga myxococcoides at 45 μg/ml, and Bacillus subtilis at 75 μg/ml. The inhibiting concentrations for tannic acid were found to be 12, 10, 45, and 30 μg/ml, respectively. Gallic acid and catechol were much less effective. Tannic acid and the tannin fraction of carob extract exerted both bacteriostatic and bactericidal effects on C. fulvus. Respiration of C. fulvus in the presence of bactericidal concentrations of tannic acid or tannin fraction of carob extract was inhibited less than 30%. A partial formation of “protoplasts” by C. fulvus was obtained after 2 hr of incubation in a growth medium to which 20% sucrose, 0.15% MgSO4·7H2O, and 10 to 50 μg/ml of tannic acid or 500μg/ml of penicillin, or both, had been added. Tannic acid and the tannin fraction of carob extract protected C. fulvus from metabolic lysis in sucrose solution. Although the growth of other microorganisms tested was only slightly affected, the morphology of some of them was drastically changed in the presence of subinhibitory concentrations of carob pod extracts of tannic acid. It is suggested that the site of action of tannins on sensitive microorganisms is primarily the cell envelope.  相似文献   

7.
Two of five Zygosaccharomyces rouxii mutants defective in salt tolerance, 152S (sat1) and 1717S (SAT3), were inviable in a nutrient medium (YPD) containing more than 1% NaCl. These two mutant cells contained significantly higher amounts of Na+ (298 μmol and 285 μmol per g cells of 152S and 1717S, respectively) but lower amounts of K+ (242 μmol and 176 μmol per g cells of 152S and 1717S, respectively) than three other mutants, 41S (sat2-1 [98 μmol Na+ and 326 μmol K+/g cells]), 197S (sat2-2 [103μmol Na+ and 336 μmol K+/g cells]), 1611S (SAT4 [139 μmol Na+ and 294 μmol K+/g cells]), as well as a wild-type strain, AN39 (61 μmol Na+ and 349 μmol K+/g cells), when cultured in YPD medium containing 0.8% NaCl. A KCl supplement, optimally 0.6 M, added to the medium somewhat restored the NaCl-hypersensitivity of 152S and 1717S with a concomitant decrease of intracellular Na+. This finding suggests that the NaCl-hypersensitive mutations are due to a defect in the Na+-regulating mechanism. The other three mutants showed weak responses to KCl in high NaCl-YPD. These five salt sensitive mutants and the wild-type strain retained the same levels of intracellular glycerol and arabitol when transferred into NaCl (5%)-YPD from YDP medium. This suggests that polyol accumulation is not the only mechanism of salt tolerance in Z. rouxii.  相似文献   

8.
The HCN content of dried Acaciafarnesiana foliage varies from 0.0 to 5.49 μmol/g among individuals within a population (X = 1.80, s.d. = 1.80 in wet season; X = 1.21, s.d. = 1.27 in dry season; n = 26) and increased in the wet season (average difference of 0.59 μmol/g) in Santa Rosa National Park, Guanacaste Province, Costa Rica. The correlation coefficient of HCN values for 26 bushes in the wet and the dry season was 0.898, suggesting that the seasonal change was proportional to the amount of HCN present in the foliage of each bush.  相似文献   

9.
The gliding bacterium Herpetosiphon giganteus Hp a2 was shown to contain -carotene, one monoglucosyloxy and two new diglucosyloxy carotenoids with a x-O-acyl-diglucosyloxy carotenoid as main component. Flexirubin-like pigments could not be detected in this organism.As in the Myxobacterales and Cytophagales (Kleinig et al., 1974) menaquinones (MK-6 and MK-7) were found to be the only isoprenoid quinones present in Herpetosiphon.The chemosystematic implications of these findings are briefly discussed.  相似文献   

10.
《Anaerobe》2000,6(3):187-196
To investigate electron transport in the dissimilatory iron-reducing isolate Geobacter metallireducens strain GS-15, assays for redox enzymes and characterizations of cytochromes were performed. G. metallireducens produced 1.56 g dry cell weight per mol etransferred when grown on benzoate and contained the following citric acid cycle enzymes (activities in nkat per mg cell protein); isocitrate dehydrogenase (0.84), coenzyme A-dependent 2-oxoglutarate: methyl viologen oxidoreductase (2.80), succinate dehydrogenase (0.80), and malate dehydrogenase (8.35). An oxygen-sensitive, soluble coenzyme A-dependent 2-oxoglutarate: ferredoxin oxidoreductase (0.14) with no NAD(P)-activity was observed. In cell suspensions NADPH, but not NADH, could reduce methyl viologen (2.45). Isocitrate and malate dehydrogenase activities were soluble enzymes that coupled with NADP and NAD, respectively. NADPH (0.94) and NADH (1.85) oxidation activities were observed in detergent solubilized, whole-cell suspensions using the artificial electron acceptor menadione. Menaquinone was observed at 1.2 μmol per g cell protein. The triheme c7cytochrome was purified and 37 amino acids were determined. The mass observed by mass spectroscopy was 9684±10 Da. The average mid-point potential for the three hemes was measured at −91 mV. The growth yield, redox reactions, and electron transfer components are discussed with regards to possible sites of energy conservation during growth on iron(III).  相似文献   

11.
Culture conditions for the extracellular production of menaquinone (MK) by a mutant strain, K3-15, of Flavobacterium sp. 238-7 were investigated. A detergent-supplemented culture medium consisted of 60 g of glycerol, 23 g of peptone, 3 g of yeast extract, 7 g of K2HPO4, 5 g of NaCl, 0.8 g of MgSO4 · 7H2O, and 0.5 g of Rikanon UA 5012 in 1 l of tap water, pH 7.0, was constructed. Amounts of MK-4, MK-6, and total MK in 1 l of the medium were 101 mg, 39 mg, and 140 mg, respectively, after 7 d of cultivation at 28°C. Further studies with some additives showed that the addition of cedar wood oil increased the productivity of MK, especially MK-4. In the presence of 0.1% Rikanon UA 5012 and 0.1% cedar wood oil, mutant strain K3-15 produced 155 mg/l intracellularly and 105 mg/l extracellularly) of MK-4 and 27 mg/l (16 mg/l intracellularly and 11 mg/l extracellularly) of MK-6, and the total amount of MK reached 182 mg/l.  相似文献   

12.
《Insect Biochemistry》1987,17(4):573-577
Taurine concentration was measured in the tissues of Schistocerca americana gregaria, Blatella orientalis and Tenebrio molitor and was found to be present in all those examined. In the locust Schistocerca gregaria it was found in particularly high concentration in active flight muscle (26 μmol/g) to a lesser extent in the eye (7 μmol/g). The thoracic concentration of taurine in developing locusts showed a strong correlation with the development of flight muscle, increasing from 4.4 to 11.3 μmol/g in the thorax during the first 24 days of adult life. Analysis of the thoracic content of taurine in adults of the three species examined confirmed that high taurine concentrations are associated with fully functional flight muscle. The concentration in the thorax of the flightless flour beetle T. molitor was only 1.79 μmol/g compared to 11.33 μmol/g for the locust. Stress due to flying and picrotoxin poisoning caused the release of taurine from the muscles into the haemolymph, causing the concentration to rise from 1.1 to 2.2 and 5.76 μmol/g respectively. Analysis of the distribution of arginine kinase showed that this release was not due to breakdown of the muscle tissue.  相似文献   

13.
Three strains of gram-negative bacteria were isolated from the mats of colorless sulfur bacteria Thioploca (Lake Baikal). The cells of new strains are motile with peritrichous flagella. Bacteria are aerobic, obligate chemoorganoheterotrophs growing within the pH range of 3.0–8.8 with the optimum at 8.3 and within the temperature range of 5–42°C with the optimum at 28°C. The cells contained menaquinones MK-8 H2 as the major component, as well as MK-7 H2 (less than 15%), while the content of ubiquinone Q8 was at least an order of magnitude lower. The G+C content of DNA in the new strains varied from 67.4 to 69.9 mol %. The level of DNA-DNA hybridization between the strains ranged from 80 to 94%, indicating that all the isolates belonged to one species. Analysis of the 16S rRNA gene nucleotide sequences of the type strain (Gen-Bank HQ400611) revealed close homologues among the known species of the genus Variovorax: 98% resemblance with the type strains of the species V. paradoxus, V. soli, V. ginsengisoli, and V. boronicumulans and 96% similarity with the type strain of V. dokdonensis. However, since the isolates differed significantly in the composition of fatty acids and isoprenoid quinones from the nearest neighbors in the phylogenetic tree, they cannot be related implicitly to the known species.  相似文献   

14.
A Gram-positive, facultatively aerobic, rod-shaped, non-motile, terminal spore-forming bacterium, designated strain G20T, was isolated from soil collected in a mountain region of Suwon, South Korea. On the basis of 16S rRNA gene sequence similarity, this strain was shown to be related to Rummeliibacillus pycnus NBRC 101231T (97.4%) and Rummeliibacillus stabekisii KSC-SF6gT (95.7%). DNA-DNA hybridization studies showed 42% and 50% similarity of strain G20T with R. pycnus NBRC 101231T and R. stabekisii KSC-SF6gT, respectively. The DNA G content of G20T was 37.8 mol%, the major cellular fatty acids were iso-C15:0 and anteiso-C15:0, and the predominant menaquinones were MK-7 and MK-8. On the basis of phylogenetic, chemotaxonomic, and phenotypic characteristics, we propose this strain to be a novel species and the third member of genus Rummeliibacillus. We suggest the name Rummeliibacillus suwonensis sp. nov. The type strain is G20T (KACC 17316T =KEMB 9005-003T =JCM 19065T).  相似文献   

15.
An actinomycete strain, 2603PH03T, was isolated from a mangrove rhizosphere soil sample collected in Wenchang, China. Phylogenetic analysis of the 16S rRNA gene sequence of strain 2603PH03T indicated high similarity to Verrucosispora gifthornensis DSM 44337T (99.4%), Verrucosispora andamanensis (99.4%), Verrucosispora fiedleri MG-37T (99.4%) and Verrucosispora maris AB18-032T (99.4%). The cell wall was found to contain meso-diaminopimelic acid and glycine. The major menaquinones were identified as MK-9(H4), MK-9(H6) and MK-9(H8), with MK-9(H2), MK-10(H2), MK-9(H10) and MK-10(H6) as minor components. The characteristic whole cell sugars were found to be xylose and mannose. The phospholipid profile was found to contain phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol, phosphatidylserine and an unidentified phospholipid. The DNA G+C content was determined to be 70.1 mol%. The results of physiological and biochemical tests and low DNA-DNA relatedness readily distinguished the isolate from the closely related species. On the basis of these phenotypic and genotypic data, strain 2603PH03T is concluded to represent a novel species of the genus Verrucosispora, for which the name Verrucosispora rhizosphaerae sp. nov. is proposed. The type strain is 2603PH03T (=CCTCC AA 2016023T = DSM 45673T).  相似文献   

16.
Biosynthesis of flexirubin (1) by Flexibacter elegans (Cytophagaceae) is closely linked to growth. Out of a number of experimental conditions tested, only lowering of the pH of the medium to slightly acid conditions led to a reduced specific pigment content. The latter returned very slowly to normal when the pH was increased again. Under no conditions was a stimulation of pigment synthesis observed. The following 14C-labelled compounds were incorporated into flexirubin with sufficiently high efficiency to accept them as precursors: acetate, malonate, tyrosine and methionine.  相似文献   

17.
A two-component model of growth and maintenance respiration is used to study the response of northern red oak (Quercus rubra L.) seedlings and 32-year-old trees to sub-ambient (10 μmol h; cumulative dose based on 7 h daily mean), ambient (43 μmol h), and twice-ambient (85 μmolh) ozone. The relative growth rates (RGR) of leaves sampled from seedlings and trees were similar across treatments, as were specific leaf respiration rates (SRR). Growth coefficients estimated from the SRR versus RGR relationship averaged 25-3 mol CO2 kg?1 leaf dry mass produced for seedlings and 21-5 mol kg?1 for trees. Maintenance coefficients ranged from 0-89 to 1-07 mol CO2 kg?1 leaf dry mass d?1 for seedlings and from 0-64 to 0-84 mol kg-1 d?1 for trees. Neither coefficient was affected by ozone. Leaves sampled throughout the growing season also showed little response of respiration to ozone. This occurred despite a 30% reduction in net photosynthesis for trees grown at twice-ambient ozone. These results suggest that growth and maintenance respiration in young northern red oak leaves are not affected by ozone and that in older leaves injury can occur without a parallel increase in so-called ‘maintenance’ respiration.  相似文献   

18.
Summary The main compound of the mixture of menaquinones isolated from Propionibacterium shermanii was identified as (II,III)-tetrahydromenaquinone-9 by thin layer chromatography, and UV as well as mass spectral methods.Abbreviations MK-9(H4) tetrahydromenaquinone-9, ect., quinone nomenclature according to the rules of IUPAC-IUB (1967) - P. Propionibacterium - TLC thin layer chromatography Parts of the results of this paper were presented at the 8th FEBS meeting, Amsterdam, 20–25 August 1972.  相似文献   

19.
A novel isolate, designated 6408J-67T, was isolated from an air sample collected from Jeju Island, Republic of Korea. Its phenotypic, genotypic, and chemotaxonomic properties were compared with those of members of the family Microbacteriaceae. The Gram-positive, aerobic, motile rod formed light yellow, smooth, circular and convex colonies. Optimal growth occurred at 30°C and pH 7.0. 16S rRNA gene sequence data showed that the isolate was a novel member of the family Microbacteriaceae, with the highest sequence similarity (97.4%) to Labedella gwakjiensis KSW2-17T and less (<97%) sequence similarity with other taxa. The major cellular fatty acids (>10% of the total) were anteiso-C15:0, iso-C14:0, and iso-C16:0. The strain also contained MK-13, MK-12, and MK-14 as the major menaquinones, as well as diphosphatidylglycerol, phosphatidylglycerol, and two unknown glycolipids. Its peptidoglycan structure was B1β with 2,4-diaminobutyric acid as a diamino acid. Mycolic acids were absent. The DNA G+C content was 68.3 mol%. Based on these phenotypic and genotypic findings, strain 6408J-67T represents a novel species of a new genus within the family Microbacteriaceae, for which the name Diaminobutyricimonas aerilata gen. nov., sp. nov. is proposed. The type strain is 6408J-67T (=KACC 15518T =NBRC 108726T).  相似文献   

20.
Ambient sea-water nitrate and tissue nitrogen (ethanol soluble nitrate and amino acids, as well as total nitrogen) of Macrocystis integrifolia Bory were monitored over a 2-yr period in Bamfield, Vancouver Island, British Columbia. Sea-water nitrate varied from a high of 12 μmol · 1?1 (individual values as high as 23 μmol · 1?1 were recorded) in late winter to below detection limits for most of the summer. Tissue nitrate and total nitrogen paralleled the ambient nitrate levels and showed summer minima and winter maxima (from 0 to 70 μmol · g fresh wt?1 for nitrate and from 0.8 to 2.9% of dry wt for total N). The nitrate uptake capacity was inversely proportional to tissue nitrate concentration and, furthermore, was much higher for subapical surface blades (60–70 nmol · cm?2 · h?1) than for older, deeper blades (5–10 nmol · cm?2 · h?1). Nitrate uptake by subapical blade disks in summer is apparently higher in dark (1.0–1.7 μmol · g fresh wt?1 · h?1) than in light (0.6–1.3 μmol · g fresh wt?1 · h?1) and the data obtained in 36–108 h experiments indicate nitrate pool sizes of 30–90 μmol · g fresh wt?1. These pools are 23 to nearly full in winter. Ammonium does not inhibit nitrate uptake. It is taken up and apparently utilized much faster than nitrate and it may well be an important source of nitrogen for marine macrophytes.  相似文献   

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