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1.
Mohammad Hassan Qureshi Chiaki Kato Koki Horikoshi 《Extremophiles : life under extreme conditions》1998,2(2):93-99
We investigated for the first time the respiratory chain system of a deep-sea barophilic bacterium, Shewanella sp. strain DB-172F. A membrane-bound ccb-type quinol oxidase, from cells grown at 60 MPa pressure, was purified to an electrophoretically homogeneous state. The purified
enzyme complex consisted of four kinds of subunits with molecular masses of 98, 66, 18.5, and 15 kDa, and it contained 0.96
mol of protoheme and 1.95 mol of covalently bound heme c per mol of enzyme. Only protoheme in the enzyme reacted with CO and CN−, and the catalytic activity of the enzyme was 50% inhibited by 4 μM CN−. The isoelectric point of the native enzyme complex was determined to be 5.0. This enzyme was specifically induced only under
conditions of elevated hydrostatic pressure, and high levels were expressed in cells grown at 60 MPa. The membranes isolated
from cells grown at atmospheric pressure (0.1 MPa) exhibited high levels of both cytochrome c oxidase and N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPDH2)-oxidase activity. These results suggest the presence of two kinds of respiratory chains regulated
in response to pressure in the deep-sea bacterium DB-172F.
Received: November 25, 1997 / Accepted: December 25, 1997 相似文献
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Several barophilic Shewanella species have been isolated from deep-sea sediments at depths of 2,485– 6,499 m. From the results of taxonomic studies, all
of these isolates have been identified as strains of Shewanella benthica except for strain DSS12. Strain DSS12 is a member of a novel, moderately barophilic Shewanella species isolated from the Ryukyu Trench at a depth of 5,110 m. On Marine Agar 2216 plates, this organism produced a violet
pigment, whereas the colonies of other isolates (S. benthica) were rose-colored. Phylogenetic analysis based on 16 S ribosomal RNA gene sequences showed that strain DSS12 represents
a separate lineage within the genus Shewanella that is closely related to S. benthica and particularly to the members of the Shewanella barophiles branch. The temperature range for growth and some of the biochemical characteristics indicate that strain DSS12
differs from other Shewanella species. Furthermore, strain DSS12 displayed a low level of DNA similarity to the Shewanella type strains. Based on these differences, it is proposed that strain DSS12 represents a new deep-sea Shewanella species. The name Shewanella violacea (JCM 10179) is proposed.
Received: 15 May 1998 / Accepted: 15 July 1998 相似文献
4.
Abstract An obligately barophilic bacterium isolated from intestinal content of a deep-sea fish ( Coryphaenoides yaquinae ), which was retrieved from a depth of 6100 m in the Northwest Pacific Ocean, swelled in the early-exponential phase, elongated in the midexponential phase, thinned in the late-exponential phase, and shortened in the stationary phase when incubated both at 82.7 MPa and at 41.4 MPa around the optimum growth pressure. The same changes were observed at any pressures where the strain could grow. We propose to call such morphological changes the SETS (swell-elongate-thin-shorten) phenomenon. These results suggest the possibility that the SETS phenomenon might occur in the growth of the strain at high-pressure deep-sea environments. 相似文献
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A novel, moderately barophilic bacterium was isolated from a sediment sample obtained from the Ryukyu Trench, at a depth
of 5110 m. The isolate, designated strain DSJ4, is a Gram-negative rod capable of growth between 4°C and 18°C under atmospheric
pressure, with optimum growth displayed at 10°C, and capable of growth at pressures between 0.1 MPa and 70 MPa at 10°C, with
optimum growth displayed at 10 MPa. Strain DSJ4 is a moderately barophilic bacterium, and shows no significant change in growth
at pressures up to 50 MPa. Phylogenetic analysis of the 16S rRNA sequence of strain DSJ4 places this strain within the Photobacterium subgroup of the family Vibrionaceae, closely related to the strain SS9 that was independently isolated from the Sulu Trough. The temperature and pressure ranges
for growth, cellular fatty acid composition, and assorted physiological and biochemical characteristics indicate that these
strains differ from other Photobacterium species. Furthermore, both SS9 and DSJ4 displayed a low level of DNA similarity to other Photobacterium type strains. Based
on these differences, these strains are proposed to represent a new deep-sea-type species. The name Photobacterium profundum (JCM10084) is proposed.
Received June 13, 1997 / Accepted: August 9, 1997 相似文献
7.
OmpH is an outer membrane protein produced by the deep-sea bacterium Photobacterium species strain SS9 in response to elevated hydrostatic pressure. In order to facilitate studies of the function of this protein, a series of OmpH+ and OmpH- strains were obtained from SS9 by Tn5 gene replacement mutagenesis. A previously isolated ompH::lacZ strain and a derivative of this strain harboring a plasmid expressing the wild-type ompH gene were also utilized. The acridine mutagen ICR 191 preferentially inhibited the growth of OmpH+ over OmpH- cells. Indeed, OmpH+ cultures treated with the mutagen rapidly accumulated mutants producing reduced levels of OmpH. In addition. OmpH+ cells took up the peptide Met-Leu-Phe approximately 15 times more rapidly than OmpH- cells. The results are consistent with the hypothesis that OmpH functions as a relatively large, nonspecific diffusion channel.Abbreviations
OMP
Outer membrane protein 相似文献
8.
Shewanella violacea DSS12 is a psychrophilic facultative piezophile isolated from the deep sea. In a previous study, we have shown that the bacterium adapted its respiratory components to alteration in growth pressure. This appears to be one of the bacterial adaptation mechanisms to high pressures. In this study, we measured the respiratory activities of S. violacea grown under various pressures. There was no significant difference between the cells grown under atmospheric pressure and a high pressure of 50 MPa relative to oxygen consumption of the cell-free extracts and inhibition patterns in the presence of KCN and antimycin A. Antimycin A did not inhibit the activity completely regardless of growth pressure, suggesting that there were complex III-containing and -eliminating pathways operating in parallel. On the other hand, there was a difference in the terminal oxidase activities. Our results showed that an inhibitor- and pressure-resistant terminal oxidase was expressed in the cells grown under high pressure. This property should contribute to the high-pressure adaptation mechanisms of S. violacea. 相似文献
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A novel barophilic, extremely thermophilic bacterium was isolated from a deep-sea hydrothermal vent chimney at the Iheya
Basin, in the Okinawa area, Japan. The cells were found to be rod shaped and surrounded by a sheath-like outer structure;
the organism did not possess flagella and was not motile. Growth was observed between 45° and 80°C (optimum, 72°C, 45 min
doubling time), pH 5.3 and 9.3 (optimum, pH 7.2–7.6), 6.6 and 79 g/l sea salts (optimum, 40 g/l), and 0.1 and 60 MPa (optimum,
20 MPa). Strain IHB1 was found to be a strictly anaerobic chemoorganotroph capable of utilizing yeast extract and proteinaceous
substrates such as peptone and tryptone. Elemental sulfur or thiosulfate acted as electron acceptors improving growth. The
isolate was able to utilize casein as a sole carbon and energy source in the presence of thiosulfate. The G + C content of
the genomic DNA was 31.4 mol%. Phylogenetic analysis based on 16S rDNA sequences and DNA–DNA hybridization analysis indicated
that the isolate is closely related to Thermosipho africanus; however, it represents a species distinct from the previously described members of the genus Thermosipho. On the basis of the physiological and molecular properties, we propose that the new isolate represents a new species, which
we name Thermosipho japonicus sp. nov. (type strain: IHB1; JCM10495).
Received: May 26, 1999 / Accepted: August 7, 1999 相似文献
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Masako Chou Takafumi Matsunaga Y. Takada Noriyuki Fukunaga 《Extremophiles : life under extreme conditions》1999,3(2):89-95
NH4
+ transport system of a psychrophilic marine bacterium Vibrio sp. strain ABE-1 (Vibrio ABE-1) was examined by measuring the uptake of [14C]methylammonium ion (14CH3NH3
+) into the intact cells. 14CH3NH3
+ uptake was detected in cells grown in medium containing glutamate as the sole nitrogen source, but not in those grown in
medium containing NH4Cl instead of glutamate. Vibrio ABE-1 did not utilize CH3NH3
+ as a carbon or nitrogen source. NH4Cl and nonradiolabeled CH3NH3
+ completely inhibited 14CH3NH3
+ uptake. These results indicate that 14CH3NH3
+ uptake in this bacterium is mediated via an NH4
+ transport system and not by a specific carrier for CH3NH3
+. The respiratory substrate succinate was required to drive 14CH3NH3
+ uptake and the uptake was completely inhibited by KCN, indicating that the uptake was energy dependent. The electrochemical
potentials of H+ and/or Na+ across membranes were suggested to be the driving forces for the transport system because the ionophores carbonylcyanide
m-chlorophenylhydrazone and monensin strongly inhibited uptake activities at pH 6.5 and 8.5, respectively. Furthermore, KCl
activated 14CH3NH3
+ uptake. The 14CH3NH3
+ uptake activity of Vibrio ABE-1 was markedly high at temperatures between 0° and 15°C, and the apparent K
m value for CH3NH3
+ of the uptake did not change significantly over the temperature range from 0° to 25°C. Thus, the NH4
+ transport system of this bacterium was highly active at low temperatures.
Received: August 1, 1998 / Accepted: October 8, 1998 相似文献
12.
Kawano H Ikegami A Nakasone K Kato C Usami R Horikoshi K 《Bioscience, biotechnology, and biochemistry》2003,67(9):1983-1985
NtrC protein of piezophilic Shewanella violacea was overexpressed and purified, to confirm the protein-DNA interaction. An electrophoretic mobility shift assay demonstrated that the NtrC recognizes the sequence for NtrC binding within the region upstream of the glnA operon. Western blot analysis also showed that the NtrC is expressed at a higher level under high-pressure conditions than under atmospheric pressure conditions. 相似文献
13.
Two extremely thermophilic archaebacteria, strains OG-1 and SM-2, were isolated from newly discovered deep-sea hydrothermal
vent areas in the western Pacific ocean. These strains were cocci, obligately anaerobic Archaea about 0.7–2 μm in diameter.
Optimum growth conditions for OG-1 and SM-2 were at 85–90°C (range 60–100°C), pH 6 (range pH 4–8), a NaCl concentration of
3% (range 1–5%), and a nutrient concentration (tryptone plus yeast extract) of 0.2% (range 0.005–5%). Elemental sulfur stimulated
the growth rate fourfold. Ammonium slightly stimulated growth. Both tryptone and yeast extract allowed growth as sole carbon
sources; these isolates were not able to utilize or grow exclusively on sucrose, glucose, maltose, succinate, pyruvate, propionate,
acetate, or free amino acids. OG-1 showed the fastest growth rate within the genus Thermococcus. Growth was inhibited by rifampicin. The DNA G+C content was 52 mol%. Sequencing of their 16S rDNA gene fragment indicated
that these isolates belonged to the genus Thermococcus. OG-1 and SM-2 were different than the described Thermococcus species. We propose that OG-1 belongs to a new species: Thermococcus peptonophilus.
Received: 8 March 1995 / Accepted: 24 May 1995 相似文献
14.
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
15.
Makoto Ashiuchi Mia Md. Zakaria Yuriko Sakaguchi Toshiharu Yagi 《FEMS microbiology letters》1999,170(1):243-249
A cryptic plasmid found at high copy number was isolated from Flavobacterium sp. KP1, a psychrophilic Gram-negative bacterium, cloned, and sequenced. The sequence will appear in the DDBJ/EMBL/GenBank databases under the accession number AB007196. The pFL1 plasmid is 2311 nucleotides in length with 32.7% GC content, and shows a distinctive nucleotide sequence without homology to other plasmids of similar length. The plasmid contains two open reading frames of significant length, ORFI and ORFII. ORFI encodes a protein similar to the replication proteins found in Gram-negative bacterial plasmids, Bacteroides fragilis plasmid pBI143 and Zymomonas mobilis plasmid pZM2. The putative translation product of ORFII shows homologies with plasmid recombination proteins found mainly in Gram-positive bacterial plasmids such as Staphylococcus aureus plasmid pT181. 相似文献
16.
Tohru Kobayashi Kohsuke Uchimura Masayuki Miyazaki Yuichi Nogi Koki Horikoshi 《Extremophiles : life under extreme conditions》2009,13(1):121-129
A high-alkaline, salt-activated alginate lyase is produced by Agarivorans sp. JAM-A1m from a deep-sea sediment off Cape Nomamisaki on Kyushu Island, Japan. Purified to homogeneity, as judged by SDS-PAGE,
the enzyme (A1m) had a molecular mass of approximately 31 kDa. The optimal pH was around 10 in glycine–NaOH buffer, and the
activity was increased to 1.8 times by adding 0.2 M NaCl. However, when the optimal pH in the presence of 0.2 M NaCl was shifted
to pH 9.0, the activity was more than 10 times compared with that at pH 9 in the absence of NaCl. A1m showed the optimal temperature
at around 30°C and was stable to incubation between pH 6 and 9. The enzyme degraded favorably mannuronate–guluronate and guluronate-rich
fragments in alginate. Shotgun cloning and sequencing of the gene for A1m revealed a 930-bp open reading frame, which encoded
a mature enzyme of 289 amino acids (32,295 Da) belonging to polysaccharide lyase family 7. The deduced amino acid sequence
showed the highest similarity to that of a Klebsiella enzyme, with only 54% identity. 相似文献
17.
《Systematic and applied microbiology》2021,44(6):126266
Three marine bacterial strains designated YLB-06T, YLB-08T and YLB-09 were isolated under high hydrostatic pressure from deep-sea sediment samples collected from the Southwest Indian Ocean. They were Gram-stain-negative, oxidase- and catalase-positive, facultative anaerobic and motile. In addition, the strains were capable of growing at 0–20 °C (optimum 4–10 °C) and 0.1–40 MPa (optimum 0.1 MPa), were psychrophiles and piezotolerant, and could use trimethylamine N-oxide (TMAO), DMSO, elemental sulfur and insoluble Fe (III) as terminal electron acceptors during anaerobic growth. Strain YLB-06T could also use nitrate, and strains YLB-08T and YLB-09 could use nitrite as a terminal electron acceptor. Phylogenetic tree analyses based on 16S rRNA gene sequences and 400 optimized universal marker sequences indicated that the strains belonged to the genus Shewanella. The 16S rRNA gene highest similarity, together with the estimated ANI and DDH values for these strains with their related type strains, were below the respective thresholds for species differentiation. The ANI and DDH values between YLB-08T and YLB-09 were 99.9% and 91.8%, respectively, implying that they should belong to the same genospecies. The YLB-06T genome had duplicated genes, and multiple movement modalities, attachment modalities, biofilm synthesis systems, intercellular interactions and a strong antioxidant system, which were all beneficial for survival in an extreme deep-sea environment. The G + C contents of strains YLB-06T, YLB-08T and YLB-09 were 45.1, 43.5 and 43.6 mol%, respectively. Based on polyphasic taxonomic properties, two novel psychropiezotolerant species are proposed, Shewanella psychropiezotolerans sp. nov. with YLB-06T (=MCCC 1A12715T = KCTC 62907T) and S. eurypsychrophilus sp. nov with YLB-08T (=MCCC 1A12718T = KCTC 62909T) as type strains. 相似文献
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Shi L Belchik SM Wang Z Kennedy DW Dohnalkova AC Marshall MJ Zachara JM Fredrickson JK 《Applied and environmental microbiology》2011,77(15):5521-5523
UndA(HRCR-6) was identified from the metal-reducing bacterium Shewanella sp. strain HRCR-6. Both in vivo and in vitro characterization results indicate that UndA(HRCR-6) is an outer membrane endecaheme c-type cytochrome and probably has a key functional role in the extracellular reduction of iron [Fe(III)] oxides and uranium [U(VI)] by Shewanella sp. HRCR-6. 相似文献