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1.
Medically important thermophilic actinomycetes were isolated from 218 (64%) of 341 samples of vegetable substrates and soil examined from sites in north-western India. Thermoactinomyces vulgaris (T. candidus) was the commonest species, occurring in 56% of samples, followed by Saccharomonospora viridis in 29%, Thermoactinomyces thalpophilus in 27%, Faenia rectivirgula (Micropolyspora faeni) in 21% and Thermoactinomyces sacchari in 14%. T. vulgaris and T. thalpophilus were isolated from all types of substrate examined, with T. vulgaris always more common than T. thalpophilus. Of the other thermophilic actinomycetes, F. rectivirgula was isolated predominantly from hay (44%) and S. viridis (56%) and T. sacchari (44%) from sugarcane bagasse. The largest populations of T. vulgaris and T. thalpophilus were found in paddy straw, followed by T. sacchari, S. viridis and F. rectivirgula in sugar-cane bagasse.The widespread occurrence of these clinically important thermophilic actinomycetes suggests that exposure of humans and animals to them may be frequent in north-western India. Studies are required to determine the prevalence of extrinsic allergic alveolitis (hypersensitivity pneumonitis) caused by thermophilic actinomycetes in the local population.  相似文献   

2.
Summary Thermophilic Actinomycetes were isolated from various peat samples and examined in detail. Most of them were classified as Thermoactinomyces vulgaris, a species which frequently occurs in very different habitats.The characters which separate Thermoactinomyces thalpophilus from Thermoactinomyces vulgaris are discussed. They are unstable and not sufficiently characteristic so that the taxonomic position of Thermoact. thalpophilus now becomes doubtful. Thermomonospora viridis comb. nov. which is distinguished by a graygreen aerial mycelium and the formation of a green pigment has been particularly studied and described. Thermoactinomyces monosporus Schütze and Thermoactinomyces viridis Schuurmans are synonyma. Streptomyces strins isolated and grown at 45° C should be called thermotolerant rather than thermophilic. They differ from known nesophilic species in their temperature requirements only.  相似文献   

3.
Thermophilic Actinomycetes were isolated by means of Andersen Sampler from four sampling sites. The total count recorded was relatively low. Four different opportunistic species were isolated in this study, Saccharomonospora viridis (syn. Thermomonospora viridis) 17%, Thermoactinomyces vulgaris (syn. T. candidus) 16.2%, Micropolyspora faeni 6.7% and Thermoactinomyces sacchari 5.2%.  相似文献   

4.
Thermophilic actinomycetes were isolated from 163 (48.95%) of 333 samples of vegetable substrates and soil from different sites in Anambra and Enugu States in Nigeria.Thermoactinomyces (Tha.) vulgaris was the most common, occurring in 32.4% of samples whileTha. thalpophilus was isolated from 20.1%.Tha. sacchari, Saccharomonospora (Sam.) viridis andSaccharopolyspora (Sap.) rectivirgula were isolated from 3–10.5% of the samples examined.Streptomyces (Stm.) thermovulgaris occurred in 2.7% andThermomonospora spp. in 0.6% of samples. Except forStm. thermovulgaris and, perhaps,Thermomonospora spp., all the species isolated are known to be allergenic in man. The five known allergenic species were abundant in hay and maize silage.T. vulgaris andT. thalpophilus were also frequently isolated from rice straw.Tha. vulgaris, Tha. thalpophilus andSap. rectivirgula were all most numerous in hay whileTha. sacchari was most numerous in maize silage. The widespread occurrence of thermophilic actinomycetes in Nigeria emphasizes the need for investigation of their role in allergic respiratory disorders.  相似文献   

5.
Summary The spores of thermophilic actinomycetes were found to be resistant to high temperatures. Spores were more resistant to dry heat than were spores in sucrose solution. The maximum resistance to 100° C in sucrose solution varied from 10 minutes forPseudonocardia thermophila to 4 hours forThermoactinomyces vulgaris.Pseudonocardia thermophila was the most sensitive to dry heat, surviving one-half hour exposure to 100° C, and 3&frac; hours to 90° C. All of the others survived 6 hours of 100° dry heat, exceptThermoactinomyces vulgaris andT. glaucus, both of which survived 15 hours. The other thermophiles tested wereStreptomyces rectus, S. thermoviolaceus subsp.pingens, S. thermovulgaris, andThermomonospora curvata.Contribution No. 342 from the Department of Botany.  相似文献   

6.
Circulating antibodies against Faenia rectivirgula, Thermoactinomyces candidus, T. vulgaris and Aspergillus fumigatus were studied in the sera of 14 clinically proven farmer's lung patients and 10 normal controls using three immunological methods. These methods were agar gel double diffusion (DD), biotin-avidin-linked immunosorbent assay (BALISA) and dot-immunobinding assay (DIBA). Agar gel diffusion, the least sensitive of the three methods, failed to detect antibodies in some of the patients, while BALISA detected antibodies even in the normal controls. However, the sensitivity of dot-immunobinding assay was in between DD and BALISA while the specificity was comparable to DD to all the antibodies except against A. fumigatus antigens. Dot-immunobinding assay gave faster results than DD and the blots can be stored as record for longer periods of time without fading.  相似文献   

7.
Maltosyl-α-cyclodextrin (6-α-maltosylcyclomaltohexaose, M-CD) was prepared from maltose and α-cyclodextrin by the reverse action of Bacillus pullulanase, and the action of α-amylases on this dextrin was examined. Among α-amylases tested, Thermoactinomyces vulgaris α-amylase (TVA) and Taka-amylase A (TAA) were found to attack the M-CD. Their action pattern on M-CD was studied. These α-amylases cleaved, first the cyclodextrin ring of M-CD, and the branched octasaccharides formed were immediately degraded to form glucose, branched tetraose, or pentaose, though the action pattern was different for TVA and TAA. In addition, TAA also split M-CD into glucose and glucosyl-α-cyclodextrin. Fission products at various stages of the reaction were separated and analyzed by paper chromatography and high performance liquid chromatography, their structures were analyzed, and the degradation pattern of M-CD was found.  相似文献   

8.
Summary Two phages isolated from Thermoactinomyces vulgaris multiplied optimally at 55–60°, and were inactivated at 80°. The two isolates had similar growth characteristics, host-range, serology and morphology. Tadpole-shaped with an elongated head, they resemble other actinophages, with long tail lacking contractile sheath and they seem specific to T. vulgaris.  相似文献   

9.
Biomass and lipid productivities of Chlorella vulgaris under different growth conditions were investigated. While autotrophic growth did provide higher cellular lipid content (38%), the lipid productivity was much lower compared with those from heterotrophic growth with acetate, glucose, or glycerol. Optimal cell growth (2 g l−1) and lipid productivity (54 mg l−1 day−1) were attained using glucose at 1% (w/v) whereas higher concentrations were inhibitory. Growth of C. vulgaris on glycerol had a similar dose effects as those from glucose. Overall, C. vulgaris is mixotrophic.  相似文献   

10.
The study was prompted by the lack of information on the role of thermophilic actinomycetes in hypersensitivity pneumonitis in India. It reports the occurrence of precipitating antibodies against clinically important thermophilic actinomycetes in the sera of a population sample of dairy herd workers, Nangali, Delhi. Of 112 workers investigated, 28 (25%) showed precipitins againstFaenia rectivirgula, 4 (3.2%) againstSaccharomonospora viridis, 2 againstThermoactinomyces thalpophilus and one each againstT. vulgaris andT. sacchari. The results of enzyme-linked immunosorbent assay (ELISA) indicated that IgG antibody activity againstF. rectivirgula was significantly higher in the symptomatic group than in the asymptomatic group (p<0.05) of workers and the controls (p<0.01). Significant difference inF. rectivirgula IgG activity was also obtained between the precipitin-positive symptomatic group and the precipitin-positive asymptomatic group (p< 0.05). In strong contrast, the IgG antibody activity againstT. thalpophilus was found to be uniformly low. A limited aeromicrobiological sampling of the dairy farm revealedS. viridis (55.8%) to be the commonest species followed byT. vulgaris (19.2%),T. thalpophilus (18.5%),F. rectivirgula (5%) andT. sacchari (15%). On the basis of suggestive clinical and laboratory findings, farmer's lung disease was suspected in four dairy herd workers. A comprehensive clinical evaluation including pulmonary function studies on the dairy herd workers and their long-term follow-up is indicated to determine the extent of respiratory morbidity caused byF. rectivirgula, S. viridis, T. thalpophilus, T. sacchari andT. vulgaris in India.  相似文献   

11.
The nonspecific acid and alkaline phosphatases of Thermoactinomyces vulgaris were found to be optimally active at 65°C and 70°C, respectively, indicating the thermophilic nature of these enzymes in this obligate thermophile. Mg2+, when added in the assay mixture (in the form of MgCl2), increased the specific activities of these enzymes without affecting their respective temperature optima. This divalent cation decreased the Arrhenius energies of activation (E A ) of both acid and alkaline phosphatases, as substantiated by Mg2+-dependent decrease in the slopes of their Arrhenius plots, which were found to be linear. Thus, Mg2+-dependent stimulation of high temperature catalysis of T. vulgaris phosphatases appeared to be accomplished by the decrease in their E A values by this divalent cation, and such unique feature of these enzymes might be associated with their evolutionary adaptation in this thermophilic actinomycete to support its growth at elevated temperatures. The catalytic role of Mg2+ in enhancing the phosphatase activities was specified by the fact that this metal ion was able to recover the enzyme activities inhibited by dialysis and EDTA.  相似文献   

12.
Chlorella vulgaris was grown photosynthetically in batch culture under nitrogen sufficiency or nitrogen limitation. The starch content of the cells was measured as the amount of glucose released by enzymic hydrolysis of partially purified starch. Nitrogen sufficient algae contained approximately 20% of their dry weight as starch, whereas in nitrogen limited cells starch comprised up to 55% of the cellular dry weight. Starch production was pH dependent; optimal production of starch was achieved between pH 7.5 and 8.0. Optimal growth of C. vulgaris occurred at pH 7.0. Carbon yield experiments showed that for every gram of carbon consumed 0.5 g of starch (glucose) could be recovered. author for correspondence  相似文献   

13.
A dried proteolytic enzyme preparation “Thermitase” is produced of the cultural solution of Thermoactinomyces vulgaris. The procedure comprises concentration, sedimentation, ethanol and sodiumsulfate precipitation and drying in laboratorial and semitechnical scale. The elimination of rape seed oil which impairs the salt sedimentation was specially taken into account. A certain sedimentation procedure using caoline or a aqueous solution of CaCl2 and Na2HPO4 or filtration was elaborated to eliminate the lipid components in the concentrated solution. The method is convenient to get good yields of the thermostable protease.  相似文献   

14.
Summary Restriction fragment length polymorphism (RFLP) was determined among P. vulgaris genotypes and Phaseolus species using 19 probes. The incidence of polymorphism was high (70–86%) between species, but relatively low (22–26%) between genotypes of P. vulgaris. Suitable probes were identified for the analysis of P. vulgaris and P. coccineus hybrids. The segregation pattern in F2 populations was Mendelian for two probes (LHB and VEE20) and non-Mendelian for GS-g, CHS, and CHI. Statistical analyses indicated gametic selection with preferential transmission of the P. vulgaris alleles, which may account for the selective recovery of P. vulgaris progeny types observed earlier. The available hybrids of P. vulgaris and P. coccineus and the high degree of interspecific RFLP will facilitate the construction of a linkage map for Phaseolus.  相似文献   

15.
为探究夏枯草中GGPPS基因的生物学特性及功能,该文在夏枯草转录组测序的基础上设计特异性引物,采用逆转录PCR技术获得夏枯草中GGPPS基因的全长核苷酸序列,并进行生物信息学分析;采用qPCR法分析PvGGPPS基因在不同外源性物质诱导下在夏枯草果穗中的表达量以及该基因在夏枯草不同组织中的表达量。结果表明:PvGGPPS基因开放阅读框1 092 bp,编码363个氨基酸,理论分子量为38 815.68 D,等电点为5.69。PvGGPPS蛋白具有异戊烯基焦磷酸合酶家族的特征结构域。系统进化树表明PvGGPPS蛋白与丹参、毛喉鞘蕊花GGPPS蛋白具有较高的亲缘关系。qPCR分析表明,PvGGPPS基因在叶中表达量高于果穗及茎。对果穗施加7种外源性物质处理24 h后,GA3处理组该基因表达量升高。PvGGPPS基因在夏枯草不同组织中表达量差异较大,且受外源物质诱导表达。该研究结果为进一步研究PvGGPPS基因对夏枯草萜类成分合成途径中的功能及表达调控奠定基础。  相似文献   

16.
The action of Thermoactinomyces vulgaris α-amylase was examined in order to elucidate whether this α-amylase catalyzes the hydrolysis of α-1, 4- and α-l, 6-glucosidic linkages in some oligosaccharides at the same catalytic site. The optimum pH for its action on maltotriose and isopanose (α-d-Glcp-(l→4)-α-d-Glcp-(1→6)-d-Glcp) was 4.5, which was the same as the value for starch and pullulan. Hydrolysis patterns of isopanose by this α-amylase were dependent on the substrate concentration. At a low substrate concentration (0.5%) equimolar maltose and glucose were produced from isopanose. At a high substrate concentration (4.0%) a small amount of isomaltose was found besides maltose and glucose, while the molar ratio of glucose to maltose plus isomaltose was unity at the early reaction stages. Hydrolysis patterns of reducing end-(14C)-labeled maltotriose was also dependent on substrate concentration. Increasing the substrate concentration from 0.5 to 4.0%, the molar ratio of labeled glucose to labeled maltose in the products was decreased from 6 to 1.5. Apparent formation of labeled glucose was depressed by the addition of isopanose to the labeled maltotriose-hydrolyzing mixture. The results above supported the view that this enzyme can hydrolyze α-l, 6-glucosidic linkage as well as α-l, 4-glucosidic linkage in isopanose or maltotriose at the same site.  相似文献   

17.
An α-amylase[α-l,4-glucan 4-glucanohydrolase, EC 3.2.1.1.], found in the culture filtrate of a strain of Thermoactinomyces vulgaris, was purified by ammonium sulfate fractionation, and DEAE-cellulose and CM-cellulose chromatographies. The purified enzyme showed a single band on disc gel electrophoresis. The optimum reaction pH and temperature were determined to be around pH 5.0 and 70°C. The isoelectric point was determined to be pH 5.2. The α-amylase was stabilized by Ca2+.

The α-amylase was found to hydrolyze pullulan to panose. Therefore, the hydrolytic pattern of this enzyme is different from those of pullulanase and isopullulanase.  相似文献   

18.
Bacteriolysis by thermophilic actinomycetes   总被引:2,自引:0,他引:2  
Eighty cultures of thermophilic actinomycetes isolated from Bombay soils were screened for lytic action on heat-killed cells of six test bacteria. The majority possessed lytic properties of varying degrees. Gram-negative bacteria were far more susceptible than gram-positive ones. Acetone-precipitated lytic enzyme systems of two cultures — A 29 (Thermomonospora fusca) and A 60 (Thermoactinomyces vulgaris) proved stable at 70 C for 4 1/2 hr and at 80 C for 50 min but were destroyed in 10 min at 100 C. Optimum activity was at 70 C and at pH 9.0. Lytic enzyme systems from both these cultures partly hydrolysed casein and rapidly liquefied gelatin.  相似文献   

19.
Crystals of Thermoactinomyces vulgaris α-amylase II, which is a new type of α-amylase having hydrolysis activities for pullulan and cyclodextrins, have been obtained and diffraction data to 2.9 Å resolution were collected. The crystal belongs to an orthorhombic system with cell dimensions of a = 119.5 Å, b = 120.6 Å, and c = 114.6 Å and a space group of P 212121. Two or three protein molecules are expected to exist in an asymmetric unit.  相似文献   

20.
Four farm ponds in various stages of Chara vulgaris succession -from the initial invasion of the alga to its nearly complete replacement-were followed each week from ice cover to ice cover. Chemical, physical, and biological parameters were analyzed in order to determine differences between ponds and to discover the biological and physicochemical factors associated with succession in Chara vulgaris ponds. The data were analyzed statistically by intraclass (single factor) analysis of variance, the Student's t-test, and stepwise multiple regression analysis.The initial invasion of C. vulgaris appeared to be preceded by a lowering of the nutrient levels of the pond by Zygnematales growth and by the substrate-stabilizing growth of Rhizoclonium sp. Chara-dominated ponds had significantly lower free CO2, bicarbonate alkalinity, and total hardness readings. Carbonate alkalinity, low phytoplankton productivity, high dissolved O2, low phosphate, and high Secchi disk readings were also characteristic of ponds in which C. vulgaris was dominant.In ponds where C. vulgaris appeared in the process of being replaced, the physicochemical factors were more closely associated with phytoplankton productivity and diversity and less closely with submerged vegetation species.Succession from C. vulgaris domination to a Najas-Potamogeton community appeared to involve shading of the former by the latter and was accelerated by the smothering effect of decaying debris caused by Gloeotrichia sp.In the final stages of succession, turbid conditions resulting from the lack of substrate-stabilizing vegetation and increased phytoplankton growth appear to have discouraged C. vulgaris growth early in the season.  相似文献   

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