共查询到20条相似文献,搜索用时 46 毫秒
1.
A procedure for rapid (7–10 days) obtaining of enrichment cultures of aboriginal thermoacidophilic microbial communities from
ores with high antimony content (Sb 26%) was developed. This technique allows for rapid alkalization of the medium due to
the abundance of calcites, as well as the low antioxidant status of the initial cells. The ore concentration in the medium
was gradually increased to 10 g/l. In the course of this process, selection of enrichment cultures containing microbial strains
preferentially oxidizing ore, S0, or Fe2+ is carried out. A combination of three enrichment cultures allowed us to rapidly (in six days) adapt the aboriginal strains
to high-density pulp (16%) in the reactor at 46°C, as well as to carry out a three-stage semi-continuous cultivation in the
reactors at D = 0.0042 h−1 and to isolate from each reactor the pure cultures of predominant bacteria involved in the process of bioleaching/oxidation
of the mixture of antimonite-containing ores and sulfide flotation concentrates. It was demonstrated that, in the microbial
community of reactor I, strain Sb-K exhibiting high rates of growth and initial substrate oxidation was predominant. In reactor
II, strain Sb-F prevailed, showing a high substrate specificity with respect to Fe2+. A sulfur-oxidizing strain involved in active oxidation of reduced inorganic sulfur compounds (RISCs) was predominant in
reactor III. Nevertheless, together, all three strains showed synergism and were able to oxidize S0, Fe2+, and sulfide minerals (including antimonite Sb2S3 in the presence of 0.02% yeast extract) in reactors. The strains differed from each other in their DNA restriction profiles,
growth rates, and the rates of inorganic substrate oxidation under mixotrophic conditions. The phenotypic properties of all
the studied isolates have a certain similarity to those of sulfobacilli. 相似文献
2.
Two proteolytic thermophilic aerobic bacterial strains, PA-9 and PA-5, were isolated from Buranga hot springs in western Uganda.
The cells were rods, approximately 10–12 μm in length and 3 μm in width. Isolate PA-9 grew at between 38°C and 68°C (optimum,
62°C), and PA-5 grew at between 37°C and 72°C (optimum, 60°C). Both isolates grew optimally at pH 7.5–8.5. Their 16S rRNA
gene sequences indicated that they belong to the newly described genus Geobacillus. Zymogram analysis of the crude enzyme extracts revealed the presence of two extracellular proteases for isolate PA-5, and
at least eight for isolate PA-9. The optimum temperature and pH for casein-degrading activity were 70°C, pH 6.5 for isolate
PA-9, but caseinolytic activity could also be observed at 2°C. In the case of isolate PA-5, optimal activity was observed
over a temperature and pH range of 50–70°C and pH 5–10, respectively.
Received: 26 November 2001 / Accepted: 12 December 2001 相似文献
3.
Field evaluations of systemic fungicides and derivatives of dithiocarbamic acid for the control of clubroot 总被引:2,自引:0,他引:2
S. T. BUCZACKI S. E. CADD J. G. OCKENDON J. G. WHITE 《The Annals of applied biology》1976,84(1):51-56
Strains of Botrytis cinerea and Mucor mucedo germinated and grew over the range 0.25°C. There were differences in germination rates and growth rates between strains of B. cinerea at any given temperature. Five of the benomyl-resistant strains germinated and grew more slowly than any of the other benomyl-resistant or benomyl-sensitive strains of B. cinerea tested. Strains of Rhizopus stolonifer and R. sexualis germinated and grew between 5 and 25°C, and although some spores germinated at 2°C, subsequent growth of the germ tubes and growth from a mycelial inoculum did not occur. Neither species germinated or grew at o°C. The effect of temperature on mycelial growth in vitro was consistent with the ability of the strains of the four species to infect strawberry fruits. 相似文献
4.
M. I. Muravyov T. A. Pivovarova T. P. Tourova A. G. Bulaev N. V. Fomchenko T. F. Kondrat’eva 《Microbiology》2010,79(3):342-348
In the process of biooxidation at 39°C in a continuous mode of the gold-arsenic concentrate from the Olympiadinskoe deposit,
which was pretreated by chemical leaching with ferric ions, by a microbial association from the BIO department reactors of
the Polyus gold mining company, a bacterial culture designated as strain HT-4 was isolated. The bacterium was a spore-forming
rod 0.5–0.6 × 1.4–2.0 μm with a flagellum. The optimal temperature for growth and Fe2+ oxidation was 55°C. The strain grew in the pH range from 1.21 to 2.10 with the optimum at pH 1.6. The organism was incapable
of lithotrophic and organotrophic growth. It grew mixotrophically by Fe2+ oxidation in the presence of 0.02% yeast extract. The DNA G+C base content was 48.6 mol %. Based on comparative phylogenetic
analysis of 1472-bp nucleotide sequences of 16S rRNA genes, strain HT-4 was classified as Sulfobacillus thermosulfidooxidans. Analysis by pulse-field gel electrophoresis revealed a unique profile of the NotI fragments of the chromosomal DNA. These results demonstrate the strain and species diversity of sulfobacilli in microbial
associations involved in biooxidation of concentrates in different technological conditions. The strain “S. olympiadicus S-5” dominated in the process of biooxidation of original concentrate not treated with ferric iron, while S. thermosulfidooxidans HT-4 was predominant in biooxidation of the chemically leached concentrate. 相似文献
5.
Halophilic archaeal strains R26T and R22 were isolated from the brown alga Laminaria produced at Dalian, Liaoning Province, China. Cells from the two strains were pleomorphic rods and Gram negative, and colonies
were red pigmented. Strains R26T and R22 were able to grow at 20–50°C (optimum 37°C) in 1.4–5.1 M NaCl (optimum 3.1–4.3 M) at pH 5.5–9.5 (optimum pH 8.0–8.5)
and neither strain required Mg2+ for growth. Cells lyse in distilled water and the minimum NaCl concentration required to prevent cell lysis was 8% (w/v)
for strain R26T and 12% (w/v) for strain R22. The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate
methyl ester and minor phosphatidylglycerol sulfate; glycolipids were not detected. Phylogenetic analyses based on 16S rRNA
genes and rpoB′ genes revealed that strains R26T and R22 formed a distinct clade with the closest relative, Natronoarchaeum mannanilyticum. The DNA G+C content of strains R26T and R22 was 65.8 and 66.4 mol%, respectively. The DNA–DNA hybridization value between strains R26T and R22 was 89%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that the strains R26T and R22 represent a novel species in a new genus within the family Halobacteriaceae, for which the name Salinarchaeum laminariae gen. nov., sp. nov. is proposed. The type strain is R26T (type strain R26T = CGMCC 1.10590T = JCM 17267T, reference strain R22 = CGMCC 1.10589). 相似文献
6.
M. V. Zaicnikova Yu. Yu. Berestovskaya V. N. Akimov N. A. Kostrikina L. V. Vasilieva 《Microbiology》2011,80(1):101-107
Two novel strains of budding bacteria, Z-0071T and Z-0072, were isolated from dystrophic humified waters formed by xylotrophic fungi in the course of spruce wood degradation.
The cells of both strains are coccoid (0.95–1.80 μm), nonmotile, single or arranged in pairs. The cells have a complex system
of intracellular membranes and are covered with fimbriae and surrounded by a mucous capsule up to 0.3 μm thick. Both strains
are aerobic organoheterotrophic, mesophilic, and acid-tolerant microorganisms that are able to grow under microaerobic conditions.
They utilize N-acetyl-glucosamine, carbohydrates, and lactate as growth substrates. The strains grow in a pH range of 4.0–7.5
with an optimum at 6.0–6.5. The temperature range for growth is 4–30°C, with an optimum at 25–28°C. Strains Z-0071T and Z-0072, inhabitants of dystrophic low-mineral waters, are NaCl-sensitive: the NaCl content in the media above 0.5 g/l
inhibited growth. The main fatty acids of strains Z-0071T and Z-0072 are C16:0, C18:1ω9c, and C18:2ω9c, 12c. The DNA G + C base content is 51.2–51.7 mol %. The sequences of the 16S rRNA gene fragments (1310 bp) of strains Z-0071T and Z-0072 were found to be identical. The obtained sequences showed a 94.3% similarity with the sequences of the type strain
of the most closely related species Singulisphaera acidiphila MOB10≅T. The phenotypic and phylogenetic properties of strains Z-0071T and Z-0072 support classification of these strains within the genus Singulisphaera as a new species Singulisphaera mucilagenosa sp. nov., with the type strain Z-0071T (VKM B-2626). 相似文献
7.
Meenakshi Banerjee R. Craig Everroad Richard W. Castenholz 《Extremophiles : life under extreme conditions》2009,13(4):707-716
Cyanobacteria that grow above seawater salinity at temperatures above 45°C have rarely been studied. Cyanobacteria of this
type of thermo-halophilic extremophile were isolated from siliceous crusts at 40–45°C in a geothermal seawater lagoon in southwest
Iceland. Iceland Clone 2e, a Leptolyngbya morphotype, was selected for further study. This culture grew only at 45–50°C, in medium ranging from 28 to 94 g L−1 TDS, It showed 3 doublings 24 h−1 under continuous illumination. This rate at 54°C was somewhat reduced, and death occurred at 58°C. A comparison of the 16S
rDNA sequence with all others in the NCBI database revealed 2 related Leptolyngbya isolates from a Greenland hot spring (13–16 g L−1 TDS). Three other similar sequences were from Leptolyngbya isolates from dry, endolithic habitats in Yellowstone National Park. All 6 formed a phylogenetic clade, suggesting common
ancestry. These strains shared many similarities to Iceland Clone 2e with respect to temperature and salinity ranges and optima. Two endolithic Leptolyngbya isolates, grown previously at 23°C in freshwater medium, grew well at 50°C but only in saline medium. This study shows that
limited genotypic similarity may reveal some salient phenotypic similarities, even when the related cyanobacteria are from
vastly different and remote habitats. 相似文献
8.
Six copper-resistant bacterial strains were isolated from wastewater of tanneries of Kasur and Rohi Nala. Two strains tolerated
copper at 380 mg/L, four up to 400 mg/L. Three strains were identified as members of the genusSalmonella; one strain was identified asStreptococcus pyrogenes, one asVagococcus fluvialis and the last was identified asEscherichia coli. The pH and temperature optimum for two of them were 7.0 and 30 °C, respectively; four strains had corresponding optima at
7.5 and 37 °C, respectively. All bacterial isola-tes showed resistance against Ag+ (280–350 mg/L), Co2+ (200–420), CrVI (280–400), Cd2+ (250–350), Hg2+ (110–200), Mn2+ (300–380), Pb2+ (300–400), Sn2+ (480–520) and Zn2+ (300–450). Largesized plasmids (>20 kb), were detected in all of the strains. After the isolates were cured of plasmids with
ethidium bromide, the efficiency of curing was estimated in the range of 60–90%. Reference strain ofE. coli was transformed with the plasmids of the bacterial isolates which grew in Luria-Bertani medium containing 100 mg/L Cu2+. The capability to adsorb and afterwards accumulate Cu2+ inside their cells was assayed by atomic absorption spectrophotometer; all bacterial cells had the ability to adsorb 50–80
% of the Cu2+ and accumulate 30–45 % Cu2+ inside them after 1 d of incubation. 相似文献
9.
The effect of different cultivation temperatures (30 and 37 °C) and pH of the media (5.5, 7.5, 8.5) on the biofilm production
was compared in Pseudomonas aeruginosa, Klebsiella pneumoniae, and Vibrio cholerae non-O1 and O1 using the crystal-violet test for estimation of quantitative production of the biofilm. Decrease (46.4–98.4
%) in the biofilm production was observed at 37 °C in 8 of the tested strains (P. aeruginosa three strains, K pneumoniae two, V. cholerae non-O1 two, and V. cholerae O1 one strain) compared with the production at 30 °C. On the other hand, five strains (P. aeruginosa 1, K. pneumoniae 3, V. cholerae non-O1 1) exhibited under these conditions a higher biofilm production (103–143 %). However, this difference was not significant
(p = 0.196). Increased pH lead to a higher biofilm production using all media tested. In P. aeruginosa the biofilm production at pH 8.5 was 139–244 %, at pH 7.5 136–164 % in comparison with pH 5.5. Similarly, in K. pneumoniae the biofilm production increased to 151–319 % at pH 8.5 while with the drop of pH to 7.5 the biofilm production was 113–177
% compared with pH 5.5. In V. cholerae non-O1 and O1 the biofilm production reached 204–329 % at pH 8.5, and 123–316 % at pH 7.5 (compared with the production at
pH 5.5). An increase in biofilm production represented an average of 169 % (p = 0.001) at pH change from 5.5 to 7.5, with the rise of pH from 5.5 to 8.5 caused an average difference of 229 % (p = 0.001). 相似文献
10.
11.
Annarita Poli Ida Romano Paolo Cordella Pierangelo Orlando Barbara Nicolaus Cristina Ceschi Berrini 《Extremophiles : life under extreme conditions》2009,13(6):867-874
A novel aerobe thermophilic endospore-forming bacterium designated strain AF/04T was isolated from thermal mud located in Euganean hot springs, Abano Terme, Padova, Italy. Strain AF/04T was Gram-positive, motile, rod-shaped, occurring in pairs, or filamentous. The isolate grew between 55 and 67°C (optimum
65°C) and at pH 6.0–7.5 (optimum pH 7.2). The strain was aerobic and grew on maltose, trehalose, and sodium acetate as sole
carbon sources. The G + C content of DNA was 53.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that
strain AF/04T falls within the genus Anoxybacillus. Levels of 16S rRNA gene sequence similarity between strain AF/04T and the type strains of recognized Anoxybacillus species ranged from 95 to 99%. Chemotaxonomic data (major isoprenoid quinone–menaquinone-7; major fatty acid iso-C15:0 and anteiso-C17:0) supported the affiliation of strain AF/04T to the genus Anoxybacillus. Based on phenotypic and chemotaxonomic characteristics, 16S rRNA gene sequence analysis and DNA–DNA hybridization data, it was proposed that strain AF/04T (=DSM 17141T = ATCC BAA 1156T) should be placed in the genus Anoxybacillus as the type strain of a novel species, Anoxybacillus thermarum sp. nov. 相似文献
12.
Three pigmented strains of halophilic archaea, RS94-RS96, were isolated from acidic foamy products of flotation enrichment of potassium minerals (Silvinit Co., Solikamsk, Russia). The cells were gram-negative, nonmotile, pleomorphic ovoids, 1.0−1.5 × 1.5−2.5 μm. The isolates were chemoorganotrophic, obligately aerobic, and catalase-positive. A range of carbohydrates and organic acids was used, as well as amino acids and peptides. The strains were halophiles and thermotolerant neutrophiles. They grew in the media with 15 to 30% NaCl (optimum at 20–22%) and 0.005–0.7 M Mg2+ (0.1–0.2 M), at pH 5.0–8.2 (optimum 7.0–7.2) and 25–55°C (optimum at 35–50°C). The major fatty acids were C16:0, C18:1, C18:0, and C16:1. The membranes contained carotenoid pigments of the bacterioruberin series and polar lipids, mostly as C20,C20 isoprenoid derivates: phosphatidylglyceromethylphosphate, phosphatidylglycerol, and three unidentified sulfated glycolipids of the S-DGD type. The DNA G+C content was 65.1–66.4 mol %. Phylogenetic analysis based on the 16S rRNA gene sequencing revealed that the thermotolerant neutrophilic isolate RS94 (DNA G+C content of 66.4 mol %) was most closely related to the nonpigmented moderate acidophile Halarchaeum acidiphilum MH1-52-1T (97.3%). Based on its phenotypic and genotypic characteristics, the organism was classified as a new species of the genus Halarchaeum with the proposed name Halarchaeum solikamskense sp. nov. The type strain is RS94T (= VKPM B-11282T). 相似文献
13.
A variety of autotrophic, sulfur- and hydrogen-oxidizing thermophilic bacteria were isolated from thermogenic composts at
temperatures of 60–80° C. All were penicillin G sensitive, which proves that they belong to the Bacteria domain. The obligately
autotrophic, non-spore-forming strains were gram-negative rods growing at 60–80°C, with an optimum at 70–75°C, but only under
microaerophilic conditions (5 kPa oxygen). These strains had similar DNA G+C content (34.7–37.6 mol%) and showed a high DNA:DNA
homology (70–87%) with Hydrogenobacter strains isolated from geothermal areas. The facultatively autotrophic strains isolated from hot composts were gram-variable
rods that formed spherical and terminal endospores, except for one strain. The strains grew at 55–75° C, with an optimum at
65–70° C. These bacteria were able to grow heterotrophically, or autotrophically with hydrogen; however, they oxidized thiosulfate
under mixotrophic growth conditions (e.g. pyruvate or hydrogen plus thiosulfate). These strains had similar DNA G+C content
(60–64 mol%) to and high DNA:DNA homology (> 75%) with the reference strain of Bacillus schlegelii. This is the first report of thermogenic composts as habitats of thermophilic sulfur- and hydrogen-oxidizing bacteria, which
to date have been known only from geothermal manifestations. This contrasts with the generally held belief that thermogenic
composts at temperatures above 60° C support only a very low diversity of obligatory heterotrophic thermophiles related to
Bacillus stearothermophilus.
Received: 20 July 1995 / Accepted: 25 September 1995 相似文献
14.
Chen C Shi R Liu BB Zhang YJ Sun HZ Li CT Tang SK Zhang LL Li WJ 《Antonie van Leeuwenhoek》2011,100(3):365-373
Two moderately halophilic, Gram-negative, rod-shaped bacteria, designated YIM 93003T and YIM 94343T, were isolated from a salt lake in Xinjiang province, north-west China. The two strains YIM 93003T and YIM 94343T grew at 20–40°C, pH 6–9, 0.5–24% (w/v) NaCl and at 20–40°C, pH 6–9, 0.5–23% (w/v) NaCl, respectively. No growth occurred
in absence of NaCl. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains YIM 93003T and YIM 94343T were phylogenetically affiliated to the genus Halomonas and exhibited sequence similarity of 97.5% and 97.4% to the type strain Halomonas anticariensis DSM 16096T, respectively. The strains possessed chemotaxonomic markers that were consistent with their classification in the genus Halomonas (Q-9 as predominant respiratory quinine; C18:1ω7c, C16:0 and C16:1 ω7c/iso-C15:02-OH as the major fatty acids). The DNA–DNA hybridization values for strains YIM 93003T and YIM 94343T, YIM 93003T and DSM 16096T, YIM 94343T and DSM 16096T were 38.1 ± 3.0, 18.3 ± 4.7, and 20.8 ± 4.6%, respectively. The G+C contents of the strains YIM 93003T and YIM 94343T were 63.4 and 64.0 mol%, respectively. Based on comparative analysis of physiological, biochemical and chemotaxonomic data,
including low DNA–DNA hybridization results, two novel species, Halomonas qijiaojingensis sp. nov., and Halomonas
flava sp. nov., are proposed. The type strains are YIM 93003T (=CCTCC AB 208133T =KCTC 22228T) and YIM 94343T (=CCTCC AB 2010382T =KCTC 23356T), respectively. 相似文献
15.
M. Lakshmikanth S. Manohar J. Patnakar P. Vaishampayan Y. Shouche J. Lalitha 《World journal of microbiology & biotechnology》2006,22(5):531-537
Summary An agar-degrading bacterium capable of utilizing agar as sole source of carbon and energy was isolated from sea water by enrichment
culture technique. The bacterium was identified as Pseudomonas aeruginosa and the culture conditions were standardized for the maximal production of extracellular agarases. The bacterium grew in
the pH range 5.0–11.0, optimal between pH 7.0 and 8.0; temperature between 25 °C and 37 °C, optimal at 30 °C and sodium chloride
concentration 0–8% and optimal at 2% respectively. The agarases secreted by Pseudomonas aeruginosa AG LSL-11 were inducible by agar and not by any other simple sugars tested. Maximal agarase production was observed at pH 8.0,
and temperature 30 °C. The bacterium had no requirement for NaCl for both growth and production of agarases. The bacterium
did not utilize other polysaccharides like ĸ-carrageenan, alginate, cellulose and CMC. The activity staining of partially purified agarase preparation after native-PAGE
revealed the presence of three different agarases, agarase LSL-11a, LSL-11b and LSL-11c, whose molecular weights were estimated
to be 76, 64 and 46 kDa respectively. 相似文献
16.
A methanogen, strain AK-1, was isolated from permanently cold marine sediments, 38- to 45-cm below the sediment surface at
Skan Bay, Alaska. The cells were highly irregular, nonmotile coccoids (diameter, 1 to 1.2 μm), occurring singly. Cells grew
by reducing CO2 with H2 or formate as electron donor. Growth on formate was much slower than that on H2. Acetate, methanol, ethanol, 1- or 2-propanol, 1- or 2-butanol and trimethylamine were not catabolized. The cells required
acetate, thiamine, riboflavin, a high concentration of vitamin B12, and peptones for growth; yeast extract stimulated growth but was not required. The cells grew fastest at 25 °C (range 5
°C to 25 °C), at a pH of 6.0 – 6.6 (growth range, pH 5.5 – 7.5), and at a salinity of 0.25 – 1.25 M Na+. Cells of this and other H2-using methanogens from saline environments metabolized H2 to a very low threshold pressure (less than 1 Pa) that was dependent on the methane partial pressure. We propose that the
threshold pressure may be limited by the energetics of catabolism. The sequence of the 16S rDNA gene of strain AK-1 was most
similar (98%) to the sequences of Methanogenium cariaci JR-1 and Methanogenium frigidum Ace-2. DNA–DNA hybridization between strain AK-1 and these two strains showed only 34.9% similarity to strain JR-1 and 56.5%
similarity to strain Ace-2. These analyses indicated strain AK-1 should be classified as a new species within the genus Methanogenium. Phenotypic differences between strain AK-1 and these strains (including growth temperature, salinity range, pH range, and
nutrient requirements) support this. Therefore, a new species, Methanogenium marinum, is proposed with strain AK-1 as type strain.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
17.
Temperature requirements for growth, reproduction and formation of macrothalli of a day-neutral strain ofScytosiphon lomentaria from the Gulf of Thessaloniki were experimentally determined and correlated with the geographic distribution in the North
Atlantic Ocean. The microthallus grew in a wider temperature interval and better at higher temperatures than did the macrothallus.
Germlings acclimated to 5 or 15°C grew sufficiently (>20% of maximum rate) and developed into macrothalli at 5–25°C and 5–27°C.
Macrothalli acclimated to 10 or 15°C grew sufficiently at 5–20°C. Macrothalli acclimated to 15°C survived at −1°C and reproduced
at 5 to 23°C. Regardless of the acclimation temperature, germlings and macrothalli grew optimally (>80% of maximum rate) at
15–25°C and at 10–15°C. The experimental data explain only the southern distribution boundary ofScytosiphon in the North Atlantic. This boundary is composite in nature: on the European coasts it is a growth boundary, whereas on the
American coasts it is a lethal one. 相似文献
18.
Studies were conducted on microfungi isolated from soils in the Windmill Islands, continental Antarctica. Growth responses
of Alternaria alternata, Chrysosporium pannorum, Nectria peziza, Thelebolus microsporus, Mycelia sterile and Phoma cf. herbarum to temperature, pH and culture media were investigated. Maximum growth occurred after 16 days, except in Nectria peziza and Thelebolus microsporus, where maximum growth occurred 12 days after inoculation. All isolates showed poor growth at 0°C. Maximum growth was obtained
with temperatures ranging from 15 to 25°C. The optimum temperature for all fungi was 20°C. An acid medium favoured growth.
Chrysosporium pannorum, Phoma cf. herbarum and Nectria peziza grew best at pH 3–4, whereas Mycelia sterile, Alternaria alternata and Thelebolus microsporus grew best at pH 5–6. The culture medium had little effect on growth, except for nutrient agar, which showed poor growth against
all isolates with the exception of Thelebolus microsporus.
Received: 11 September 1996 / Accepted: 13 January 1997 相似文献
19.
Three strains of gram-positive, motile, rod-shaped and boron (B)-tolerant bacterium were isolated from naturally B containing
soil of Hisarcik area in the Kutahya Province, Turkey. The strains, designated as T-14A, T-15ZT and T-17s, produced spherical or ellipsoidal endospores in a terminal bulging sporangium. The strains required B for the
growth and can tolerate more than 450 mM B. These also tolerated up to 7.0% (w/v) NaCl in the presence of 50 mM B in agar
medium but grew optimally without NaCl. The temperature range for growth was 16–37°C (optimal of 30°C), whereas the pH range
was 6.5–9.0 (optimal of 7.5–8.5). The DNA G + C content was 41.1–42.2 mol% and the predominant cellular fatty acid was iso-C15:0. The major respiratory quinone system was detected as MK-7 and the diamino acid of the peptidoglycan was meso-diaminopimelic acid. Based on phenotypic and chemotaxonomic characteristics, phylogenetic analysis of 16S rRNA gene sequences
data and DNA–DNA re-association values, we concluded that the three strains belong to a novel species of the genus Bacillus, the type strain of which is T-15ZT and for which we proposed the name, B. boroniphilus sp. nov. (DSM 17376T = IAM 15287T = ATCC BAA-1204T). 相似文献
20.
A phosphate solubilizing and antagonistic bacterial strain, isolated from a Western Ghat forest soil in Kerala province, India
(designated as NII-0906), showed cold tolerance and grew from 10 to 37°C (optimum temperature 30°C). It was a Gram-positive,
rod shaped, 0.8–1.6 μm in size, and exhibited tolerance to a wide pH range (5–12; optimum 7.0) and salt concentration up to
7% (w/v). The isolate showed maximum similarity with Exiguobacterium marinum TF-80T based on 16S rRNA analysis. It solubilized tricalcium phosphate under in vitro conditions. The phosphate solubilization was
estimated along a temperature range (5–40°C), and maximum activity (84.7 μg mL−1 day−1) was recorded at 30°C after 10 days of incubation. The phosphate solubilizing activity coincided with a concomitant decrease
in pH of the medium. The isolate also exhibited antifungal activity against phytopathogenic fungi in Petri dish assays and
produced siderophore and hydrogen cyanide. The strain’s plant growth promotion properties were demonstrated through a cowpea-based
bioassay under greenhouse conditions. The bacterial inoculation resulted in significant increment in plant root, stem and
as well as in plant biomass. Further, scanning electron microscopic study revealed the root colonization in cowpea. These
results could offer potential perspective for the strain to be used as plant growth-promoting rhizobacteria, which could be
used as an inoculant for regional crops. 相似文献