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1.
A Kademi L Fakhreddine N Aït-Abdelkader J C Baratti 《Journal of industrial microbiology & biotechnology》1999,23(3):188-193
Growth and esterase production (activity on p-nitrophenyl caprylate) by the newly isolated Bacillus circulans MAS2 bacterial strain were studied. The growth rate at 50°C was high (0.9 h-1) on LB medium with glucose added. Esterase production followed growth with the majority of activity being intracellular during
exponential growth phase. During stationary phase, the esterase activity was released in the culture medium. The strain was
able to grow at 35– 55°C with maximum growth rate at 50°C, showing a pattern typical of a moderate thermophile. Growth occurred
at pH 6–9 with a maximum at 8, with a similar pattern for the esterase production. Addition of glucose, fructose, sucrose
or sodium acetate greatly promoted both growth and esterase production while starch, inulin, tributyrin or glycerol showed
no effect. Complex nitrogen sources such as tryptone or yeast extract increased growth and esterase production while mineral
sources (ammonium chloride or sulfate), glycine or glutamate showed no effect. An increase of tryptone plus yeast extract
and glucose concentrations stimulated growth and esterase production which reached 160 U L−1.
Received 17 March 1999/ Accepted in revised form 25 June 1999 相似文献
2.
Grote R Li L Tamaoka J Kato C Horikoshi K Antranikian G 《Extremophiles : life under extreme conditions》1999,3(1):55-62
A novel coccoid-shaped, hyperthermophilic, anaerobic archaeon, strain RG-20, was isolated from a deep-sea hydrothermal vent
fluid sample taken at 1394-m depth at the Mid-Okinawa Trough (27°32.7′N, 126°58.5′E). Cells of this isolate occur singly or
in pairs and are about 0.8 to 2 μm in diameter. Growth was observed at temperatures between 50° and 93°C, with an optimum
at 85°C. The pH range for growth is 5.0–9.0, with an optimum around 7.0. Strain RG-20 requires 1%–4% of NaCl for growth, and
cell lysis occurs at concentrations below 1%. The newly isolated strain grows preferentially in the presence of elemental
sulfur on proteinaceous substrates such as yeast extract, peptone, or tryptone, and no growth was observed on carbohydrates,
carboxylic acids, alcohols, or lipids. This microorganism is resistant to streptomycin, chloramphenicol, ampicillin, and kanamycin
at concentrations up to 150 μg/ml, but is susceptible to rifampicin. Analysis of the hydrolyzed core lipids by thin-layer
chromatography (TLC) revealed the presence of archaeol and caldarchaeol. The mol% G+C content of the DNA is 55.8. Partial
sequencing of the 16S rDNA indicates that strain RG-20 belongs to the genus Thermococcus. Considering these data and on the basis of the results from DNA-DNA hybridization studies, we propose that this strain should
be classified as a new species named Thermococcus siculi (si′cu.li. L. gen. n. siculi, of the deep-sea [siculum, deep-sea in literature of Ovid], referring to the location of the sample site, a deep-sea hydrothermal vent). The type strain
is isolate RG-20 (DSM No. 12349).
Received: May 11, 1998 / Accepted: July 24, 1998 相似文献
3.
R. Dirmeier Martin Keller Doris Hafenbradl Franz-Josef Braun Reinhard Rachel Siegfried Burggraf Karl O. Stetter 《Extremophiles : life under extreme conditions》1998,2(2):109-114
From a shallow marine hydrothermal system at Vulcano (Italy), a new hyperthermophilic member of the Archaea was isolated. The cells are coccoid – shaped and possess up to five flagella. They grow between 56° and 93°C (optimum 85°C)
and pH 5.0–9.5 (optimum 9.0). The organism is strictly anaerobic and grows heterotrophically on defined amino acids and complex
organic substrates such as casamino acids, yeast extract, peptone, meat extract, tryptone, and casein. Polysulfide and elemental
sulfur are reduced to H2S. In the absence of polysulfide or elemental sulfur, the isolate grows at a significantly reduced rate. Growth is not influenced
by the presence of H2. DNA–DNA hybridization and 16S rRNA partial sequences indicated that the new isolate belongs to the genus Thermococcus, and represents a new species, Thermococcus acidaminovorans. The type strain is isolate AEDII10 (DSM 11906).
Received: September 24, 1997 / Accepted: January 1, 1998 相似文献
4.
M. Keller Franz-Josef Braun Reinhard Dirmeier Doris Hafenbradl Siegfried Burggraf Reinhard Rachel Karl O. Stetter 《Archives of microbiology》1995,164(6):390-395
A novel coccoid-shaped, hyperthermophilic, heterotrophic member of the archaea was isolated from a shallow marine hydrothermal
system at Vulcano Island, Italy. The isolate grew between 56 and 90° C with an optimum around 85° C. The pH range for growth
was 6.5 to 10.5, with an optimum around 9.0. Polysulfide and elemental sulfur were reduced to H2S. Sulfur stimulated the growth rate. The isolate fermented yeast extract, peptone, meat extract, tryptone, and casein. Isovalerate,
isobutyrate, propionate, acetate, CO2, NH3, and H2S (in the presence of S°) were detected as end products. Growth was not inhibited by H2. Based on DNA-DNA hybridization and 16S rRNA partial sequences, the new isolate represents a new species of Thermococcus, which we named Thermococcus alcaliphilus. The type strain is isolate AEDII12 (DSM 10322)
Received: 7 July 1995 / Accepted: 25 August 1995 相似文献
5.
R. Huber Josef Stöhr Sabine Hohenhaus Reinhard Rachel Siegfried Burggraf Holger W. Jannasch Karl O. Stetter 《Archives of microbiology》1995,164(4):255-264
From a hydrothermal vent site off the Mexican west coast (20°50′N, 109°06′W) at a depth of 2,600 m, a novel, hyperthermophilic,
anaerobic archaeum was isolated. Cells were round to slightly irregular cocci, 1.2–2.5 μm in diameter and were motile by means
of a tuft of flagella. The new isolate grew between 60 and 93°C (optimum: 85°C), from pH 3.5 to 9 (optimum: pH 6.7), and from
0.8 to 8% NaCl (optimum: 2%). The isolate was an obligate organotroph, using chitin, yeast extract, meat extract, and peptone
for growth. Chitin was fermented to H2, CO2, NH3, acetate, and formate. H2S was formed in the presence of sulfur. The chitinoclastic enzyme system was oxygen-stable, cell-associated, and inducible
by chitin. The cell wall was composed of a surface layer of hex- americ protein complexes arranged on a p6 lattice. The core
lipids consisted of glycerol diphytanyl diethers and acyclic and cyclic glycerol diphytanyl tetraethers. The G+C content was
46.5 mol%. DNA/DNA hybridization and 16S rRNA sequencing indicated that the new isolate belongs to the genus Thermococcus, representing a new species, Thermococcus chitonophagus. The type strain is isolate GC74, DSM 10152.
Received: 8 May 1995 / Accepted: 26 June 1995 相似文献
6.
Pyrococcus horikoshii sp. nov., a hyperthermophilic archaeon isolated from a hydrothermal vent at the Okinawa Trough 总被引:3,自引:3,他引:0
Juan M. González Yaeko Masuchi F. T. Robb James W. Ammerman Dennis L. Maeder Miki Yanagibayashi J. Tamaoka Chiaki Kato 《Extremophiles : life under extreme conditions》1998,2(2):123-130
A hyperthermophilic, anaerobic archaeon was isolated from hydrothermal fluid samples obtained at the Okinawa Trough vents
in the NE Pacific Ocean, at a depth of 1395 m. The strain is obligately heterotrophic, and utilizes complex proteinaceous
media (peptone, tryptone, or yeast extract), or a 21-amino-acid mixture supplemented with vitamins, as growth substrates.
Sulfur greatly enhances growth. The cells are irregular cocci with a tuft of flagella, growing optimally at 98°C (maximum
growth temperature 102°C), but capable of prolonged survival at 105°C. Optimum growth was at pH 7 (range 5–8) and NaCl concentration
2.4% (range 1%–5%). Tryptophan was required for growth, in contrast to the closely related strains Pyrococcus furiosus and P. abyssi. Thin sections of the cell, viewed by transmission electron microscopy, revealed a periplasmic space similar in appearance
to the envelope of P. furiosus. The predominant cell membrane component was tetraether lipid, with minor amounts of diether lipids. Treatment of the cells
by mild osmotic shock released an extract that contained a Zn2+-dependent alkaline phosphatase. Phylogenetic analysis of the sequences encoding 16S rRNA and glutamate dehydrogenase places
the isolate with certainty within the genus Pyrococcus although there is relatively low DNA–DNA hybridization (<63%) with described species of this genus. Based on the reported
results, we propose a new species, to be named Pyrococcus horikoshii sp. nov.
Received: December 10, 1997 / Accepted: February 4, 1998 相似文献
7.
Kecha M Benallaoua S Touzel JP Bonaly R Duchiron F 《Extremophiles : life under extreme conditions》2007,11(1):65-73
A hyperthermophilic anaerobic archeon, strain HT3, was isolated from hydrothermal hot spring in Northeast Algeria. The strain
is a regular coccus, highly motile, obligatory anaerobic, heterotrophic. It utilizes proteinaceous complex media (peptone,
tryptone or yeast extract). Sulfur is reduced to Hydrogen sulfide and enhances growth. It shares with other Pyrococcus species the heterotrophic mode of nutrition, the hyperthermophily, the ability to utilize amino acids as sole carbon and nitrogen
sources and the ether lipid composition. The optimal growth occurs at 80–85°C, pH 7.5 and 1.5% NaCl. The G + C content was
43 mol%. Considering its morphology, physiological properties, nutritional features and phylogenetic analyses based on 16S
rRNA gene sequencing, this strain is described as a new terrestrial isolate pertaining to the genus Pyrococcus. 相似文献
8.
Abdeljabbar Hedi Marie-Laure Fardeau Najla Sadfi Abdellatif Boudabous Bernard Ollivier Jean-Luc Cayol 《Extremophiles : life under extreme conditions》2009,13(2):313-319
A new halophilic anaerobe was isolated from the hypersaline surface sediments of El-Djerid Chott, Tunisia. The isolate, designated
as strain 6SANG, grew at NaCl concentrations ranging from 14 to 30%, with an optimum at 20–22%. Strain 6SANG was a non-spore-forming,
non-motile, rod-shaped bacterium, appearing singly, in pairs, or occasionally as long chains (0.7–1 × 4–13 μm) and showed
a Gram-negative-like cell wall pattern. It grew optimally at pH values between 7.2 and 7.4, but had a very broad pH range
for growth (5.9–8.4). Optimum temperature for growth was 42°C (range 30–50°C). Strain 6SANG required yeast extract for growth
on sugars. Glucose, sucrose, galactose, mannose, maltose, cellobiose, pyruvate, and starch were fermented. The end products
from glucose fermentation were acetate, butyrate, lactate, H2, and CO2. The G + C ratio of the DNA was 34.3 mol%. Strain 6SANG exhibited 16S rRNA gene sequence similarity values of 91–92% with
members of the genus Halobacteroides, H. halobius being its closest phylogenetic relative. Based on phenotypic and phylogenetic characteristics, we propose that this bacterium
be classified as a novel species of a novel genus, Halanaerobaculum tunisiense gen. nov., sp. nov. The type strain is 6SANGT (=DSM 19997T = JCM 15060T). 相似文献
9.
Barbara Nicolaus Roberta Improta Maria C. Manca Licia Lama Enrico Esposito Agata Gambacorta 《Polar Biology》1998,19(2):133-141
The isolation of three species from soil samples from an unexplored site in Antarctica, belonging to the Alicyclobacillus genus, is reported. The isolates, named MR1, MR2 and MR4, were from 30 samples of geothermal soil from Mount Rittmann. All
the isolates had lipids based mainly on fatty acids possessing a terminal cyclohexane; hopanoid and quinones of MK-7 were
also present. All isolates were characterized by phenotypic features and the isolate MR1 was subjected to genetic analyses.
The isolates were thermoacidophilic, showing an optimum temperature of 63°C and an optimum pH of 3.5–4.0. They were able to
grow in the temperature range 45–70°C. The percentage C+G of DNA of MR1 was 64.9% and showed a 16S rDNA similarity of 99.3%
with Alicyclobacillus acidocaldarius ATCC 43034 and a DNA-DNA homology of 69.7% with A. acidocaldarius DSM 446. The strain MR1 is unable to produce amylolytic activity under different growth conditions. It is proposed to accommodate
MR1 in the genus Alicyclobacillus as subspecies rittmannii of A. acidocaldarius.
Received: 29 May 1997 / Accepted: 26 September 1997 相似文献
10.
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
11.
Silke Ehrich Doris Behrens Elena Lebedeva Wolfgang Ludwig Eberhard Bock 《Archives of microbiology》1995,164(1):16-23
A gram-negative, non-motile, non-marine, nitrite-oxidizing bacterium was isolated from an enrichment culture initiated with
a sample from a partially corroded area of an iron pipe of a heating system in Moscow, Russia. The cells were 0.9–2.2 μm ×
0.2–0.4 μm in size. They were helical- to vibroid-shaped and often formed spirals with up to three turns 0.8–1.0 μm in width.
The organism possessed an enlarged periplasmic space and lacked intracytoplasmic membranes and carboxysomes. The cells tended
to excrete extracellular polymers, forming aggregates. The bacterium grew optimally at 39°C and pH 7.6– 8.0 in a mineral medium
with nitrite as sole energy source and carbon dioxide as sole carbon source. The optimal nitrite concentration was 0.35 mM.
Nitrite was oxidized to nitrate stoichiometrically. The doubling time was 12 h in a mineral medium with 7.5 mM nitrite. The
cell yield was low; only 0.9 mg protein/l was formed during oxidation of 7.5 mM nitrite. Under anoxic conditions, hydrogen
was used as electron donor with nitrate as electron acceptor. Organic matter (yeast extract, meat extract, peptone) supported
neither mixotrophic nor heterotrophic growth. At concentrations as low as 0.75 g organic matter/l or higher, growth of nitrite-oxidizing
cells was inhibited. The cells contained cytochromes of the b- and c-type. The G+C content of DNA was 56.9 ± 0.4 mol%. The chemolithoautotrophic nitrite-oxidizer differed from the terrestrial
members of the genus Nitrobacter with regard to morphology and substrate range and equaled Nitrospira marina in both characteristics. The isolated bacterium is designated as a new species of the genus Nitrospira. Comparative analysis of 16S rRNA gene sequences revealed a moderate phylogenetic relationship to Nitrospira marina, leptospirilla, Thermodesulfovibrio yellowstonii, "Magnetobacterium bavaricum," and the isolate OPI-2. Initial evidence is given that these organisms represent a new phylum of the domain bacteria.
Received: 17 February 1995 / Accepted: 18 April 1995 相似文献
12.
Mei-Chin Lai Chi-Ming Shu Ming-Shing Chiou Tong-Yung Hong Ming-Jen Chuang Jack Jay Hua 《Current microbiology》1999,39(2):79-84
A new methanogenic isolate, designated as strain N2M9705 (=OCM 668), was isolated from an aquaculture fishpond near Wang-gong,
Taiwan. This strain grew on trimethylamine and methanol, but it did not catabolize H2-CO2, acetate, or formate. The cells were stained Gram-negative, nonmotile, irregular coccus 0.6–0.8 μm in diameter. Gas vacuoles
were observed and cell aggregated to form various sizes of granules. Cells grew optimally at 32°–37°C with 1% NaCl. The pH
range of growth was 6.2–7.4, and higher pH inhibited the cell growth. The cells grew well in minimal medium, but growth was
greatly stimulated by yeast extract and peptone. A comparison of 16S rDNA sequences of this organism phylogenetically related
to Methanosarcina mazei. This is the first report of methyltrophic methanogenic isolated from an aquaculture fishpond.
Received: 16 March 1999 / Accepted: 16 April 1999 相似文献
13.
Influence of complex nutrients, temperature and pH on bacteriocin production by Lactobacillus sakei CCUG 42687 总被引:1,自引:0,他引:1
Aasen IM Møretrø T Katla T Axelsson L Storrø I 《Applied microbiology and biotechnology》2000,53(2):159-166
The effects of process conditions and growth kinetics on the production of the bacteriocin sakacin P by Lactobacillus sakei CCUG 42687 have been studied in pH-controlled fermentations. The fermentations could be divided into phases based on the
growth kinetics, phase one being a short period of exponential growth, and three subsequent ones being phases of with decreasing
specific growth rate. Sakacin P production was maximal at 20 °C. At higher temperatures (25–30 °C) the production ceased at
lower cell masses, when less glucose was consumed, resulting in much lower sakacin P concentrations. With similar media and
pH, the maximum sakacin P concentration at 20 °C was seven times higher than that at 30 °C. The growth rate increased with
increasing concentrations of yeast extract, and the maximum concentration and specific production rate of sakacin P increased
concomitantly. Increasing tryptone concentrations also had a positive influence upon sakacin P production, though the effect
was significantly lower than that of yeast extract. The maximum sakacin P concentration obtained in this study was 20.5 mg
l−1. On the basis of the growth and production kinetics, possible metabolic regulation of bacteriocin synthesis is discussed,
e.g. the effects of availability of essential amino acids, other nutrients, and energy.
Received: 7 June 1999 / Received revision: 15 September 1999 / Accepted: 17 September 1999 相似文献
14.
Solveig K. Petursdottir Jakob K. Kristjansson 《Extremophiles : life under extreme conditions》1997,1(2):94-99
Mesophilic, moderately halophilic bacteria were isolated from a silica-rich geothermal lake, the Blue Lagoon in Iceland.
The isolates are strictly aerobic, but reduce nitrate to nitrite, and are oxidase- and catalase-positive. The nonsporeforming
and nonmotile Gram negative rods are 0.6–0.8 μm in diameter and variable in length (9–18 μm), and contain gas vacuoles. The
GC content in their DNA is 66.15%. The minimum, optimum, and maximum temperatures for growth are 22°C, 45°:C, and 50°C, respectively.
The isolates do not grow without added salt in the medium and can grow at up to 7% NaCl (w/v). The optimal salinity for growth
is 3.5%–4% NaCl. The pH range for growth is 6.5–8.5, with the optimal pH at 7.0. At optimal conditions the bacterium has a
doubling time of 80 min. The main cytochrome is a membrane-bound cytochrome c with an α-peak at 549 nm. Sequencing of 16S rRNA from the type strain ITI-1157 revealed it to be a proteobacterium of the
α-subclass with the closest relatives being Roseobacter litoralis and Paracoccus kocurii. The new isolates do not contain bacteriochlorophyll a and are considered to represent a new genus and a new species, Silicibacter lacuscaerulensis.
Received: September 17, 1996 / Accepted: December 10, 1996 相似文献
15.
Annukka E. Mäkinen Anna H. Kaksonen Jaakko A. Puhakka 《Extremophiles : life under extreme conditions》2009,13(3):505-510
A thermophilic, rod-shaped, motile, Gram-positive, spore-forming bacterium strain 70BT was isolated from a geothermally active underground mine in Japan. The temperature and pH range for growth was 50–81°C (optimum
71°C) and 6.2–9.8 (optimum pH 7–7.5), respectively. Growth occurred in the presence 0–2% NaCl (optimum 1% NaCl). Strain 70BT could utilize glucose, fructose, mannose, mannitol, pyruvate, cellobiose and tryptone as substrates. Thiosulfate was used
as electron acceptor. Major whole-cell fatty acids were iso-C15:0, C16:0 DMA (dimethyl acetal), C16:0 and anteiso-C15:0. The G+C mol% of the DNA was 44.2%. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the closest relatives
of strain 70BT were Thermosediminibacter oceani DSM 16646T (94% similarity) and Thermosediminibacter litoriperuensis DSM 16647 (93% similarity). The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain 70BT represents a novel species in a new genus, for which the name Thermovorax subterraneus gen. nov., sp. nov. is proposed. The type strain of Thermovorax subterraneus is 70BT (=DSM 21563 = JCM 15541). 相似文献
16.
Bifidobacteria play an important role in human health including the enhancement of resistance against infection in infants.
To develop an inexpensive whey-based medium for Bifidobaterium bifidum, potential growth promoters — yeast extract, casein, bovine casein digest, tryptone, peptone and glucosamine — singly or
in combinations, were evaluated for their bifidus growth-promoting activity. The effect of environmental conditions on growth
in cheese whey was also evaluated. A whey-based medium for B. bifidum was formulated. Cheese whey supplemented with N-acetylglucosamine (1 mg/ml) and yeast extract (10 mg/ml) in the presence of sodium thioglycolate (0.1%) at pH 6.8 promoted
the growth of B. bifidum at 37°C. Journal of Industrial Microbiology & Biotechnology (2000) 25, 177–179.
Received 20 May 2000/ Accepted in revised form 20 July 2000 相似文献
17.
Yamamoto M Ishii A Nogi Y Inoue A Ito M 《Extremophiles : life under extreme conditions》2006,10(5):421-426
Two novel denitrifying alkalithermophilic bacteria, AT-1 and AT-2, were isolated from manure-amended soil. The isolates grew at 35–65°C with an optimum temperature at 50–60°C, and pH 6.5–10.0 with an optimum pH at 9.5. Both isolates were Gram-positive, facultative anaerobic, non-motile rod-shaped bacteria. A phylogenetic analysis based on 16S rRNA sequence data indicated that both AT-1 and AT-2 are members of the genus Anoxybacillus. DNA-DNA hybridization revealed moderate relatedness between AT-1 and AT-2 and one phylogenetically related strain, A. pushchinensis K1 (69.5 and 69.1%, respectively). Comparative analysis of morphology and biochemical characteristics of the two isolates also showed similarity to A. pushchinensis K1. Based on these results, we identified AT-1 and AT-2 as A. pushchinensis. To our knowledge, this is the first report of denitrifying bacterium isolated from alkalithermophilic Anoxybacillus spp. 相似文献
18.
C. K. Deepa Syed G. Dastager Ashok Pandey 《World journal of microbiology & biotechnology》2010,26(7):1233-1240
The efficacy of four potential phosphate solubilizing Enterobacter isolated from non-rhizospheric soil in Western ghat forest in India. Plant growth promoting ability of these isolates was evaluated in cowpea. All are gram negative, rod shaped,
0.8–1.6 mm in size, and psychrotrophic in nature, grow from 5 to 40°C (optimum temp. 28 ± 2°C). All isolates exhibits growth
at a wide range of pH 6–12, optimum at pH 7.0 and tolerates up to 7% (w/v) salt concentration. 16S rRNA gene sequencing reveals
the confirmation of isolates to Enterobacter aerogenes sp. (NII-0907 and NII-0929), Enterobacter cloacae subsp. cloacae sp. (NII-0931) and Enterobacter asburiae sp. (NII-0934) with which they share >99% sequence similarity. Under in vitro conditions, all the four isolates were found
to produce indole acetic acid, P-solubilization and hydrogen cyanide. The P-solubilizing activity coincided with a concomitant
decrease in pH of the medium (pH 7.0–<3.0). The plant growth promotion properties were demonstrated through a cow pea (Vigna unguiculata (L.) walp) based bioassay under greenhouse conditions. Although the bacterial inoculation was found to result in significant increment
in root, shoot and biomass and it stimulated bacterial counts in the rhizosphere. Hence, these isolates can further formulated
and used for field application. 相似文献
19.
Prokofeva MI Kublanov IV Nercessian O Tourova TP Kolganova TV Lebedinsky AV Bonch-Osmolovskaya EA Spring S Jeanthon C 《Extremophiles : life under extreme conditions》2005,9(6):437-448
Metabolic and phylogenetic diversity of cultivated anaerobic microorganisms from acidic continental hot springs and deep-sea hydrothermal vents was studied by molecular and microbiological methods. Anaerobic organotrophic enrichment cultures growing at pH 3.5–4.0 and 60 or 85°C with organic energy sources were obtained from samples of acidic hot springs of Kamchatka Peninsula (Pauzhetka, Moutnovski Volcano, Uzon Caldera) and Kunashir Island (South Kurils) as well as from the samples of chimneys of East Pacific Rise (13°N). The analyses of clone libraries obtained from terrestrial enrichment cultures growing at 60°C revealed the presence of archaea of genus Thermoplasma and bacteria of genus Thermoanaerobacter. Bacterial isolates from these enrichments were shown to belong to genera Thermoanaerobacter and Thermoanaerobacterium, being acidotolerant with the pH optimum for growth at 5.5–6.0 and the pH minimum at 3.0. At 85°C, domination of thermoacidophilic archaea of genus Acidilobus in terrestrial enrichments was found by both molecular and microbiological methods. Five isolates belonging to this genus possessed some phenotypic features that were new for this genus, such as flagellation or the ability to grow on monosaccharides or disaccharides. Analyses of clone libraries from the deep-sea thermoacidophilic enrichment cultures showed that the representatives of the genus Thermococcus were present at both 60 and 85°C. From the 60°C deep-sea enrichment, a strain belonging to Thermoanaerobacter siderophilus was isolated. It grew optimally at pH 6.0 with the minimum pH for growth at 3.0 and with salinity optimum at 0–2.5% NaCl and the maximum at 7%, thus differing significantly from the type strain. These data show that fermentative degradation of organic matter may occur at low pH and wide temperature range in both terrestrial and deep-sea habitats and can be performed by acidophilic or acidotolerant thermophilic prokaryotes. 相似文献
20.
Zavarzina DG Sokolova TG Tourova TP Chernyh NA Kostrikina NA Bonch-Osmolovskaya EA 《Extremophiles : life under extreme conditions》2007,11(1):1-7
A moderately thermophilic, sporeforming bacterium able to reduce amorphous Fe(III)-hydroxide was isolated from ferric deposits
of a terrestrial hydrothermal spring, Kunashir Island (Kurils), and designated as strain Z-0001. Cells of strain Z-0001 were
straight, Gram-positive rods, slowly motile. Strain Z-0001 was found to be an obligate anaerobe. It grew in the temperature
range from 45 to 70°C with an optimum at 57–60°C, in a pH range from 5.9 to 8.0 with an optimum at 7.0–7.2, and in NaCl concentration
range 0–3.5% with an optimum at 0%. Molecular hydrogen, acetate, peptone, yeast and beef extracts, glycogen, glycolate, pyruvate,
betaine, choline, N-acetyl-d-glucosamine and casamino acids were used as energy substrates for growth in presence of Fe(III) as an electron acceptor.
Sugars did not support growth. Magnetite, Mn(IV) and anthraquinone-2,6-disulfonate served as the alternative electron acceptors,
supporting the growth of isolate Z-0001 with acetate as electron donor. Formation of magnetite was observed when amorphous
Fe(III) hydroxide was used as electron acceptor. Yeast extract, if added, stimulated growth, but was not required. Isolate
Z-0001 was able to grow chemolithoautotrophicaly with molecular hydrogen as the only energy substrate, Fe(III) as electron
acceptor and CO2 as the carbon source. Isolate Z-0001 was able to grow with 100% CO as the sole energy source, producing H2 and CO2, requiring the presence of 0.2 g l−1 of acetate as the carbon source. The G+C content of strain Z-0001T DNA G+C was 47.8 mol%. Based on 16S rRNA sequence analyses strain Z-0001 fell into the cluster of family Peptococcaceae, within the low G+C content Gram-Positive bacteria, clustering with Thermincola carboxydophila (98% similarity). DNA–DNA hybridization with T. carboxydophila was 27%. On the basis of physiological and phylogenetic data it is proposed that strain Z-0001T (=DSMZ 14005, VKM B-2307) should be placed in the genus Thermincola as a new species Thermincola ferriacetica sp. nov.
The GenBank accession number for the sequence reported in the paper is AY 631277. 相似文献