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At least 19 recordsLinked to original sources

PubMed2003

Characterization of several Psychrobacter strains isolated from Antarctic environments and description of Psychrobacter luti sp. nov. and Psychrobacter fozii sp. nov.

Eleven psychrophilic bacteria isolated from Antarctic coastal marine environments were subjected to a polyphasic taxonomic study. The isolates were oxidase-positive, halotolerant, gram-negative, non-motile coccobacilli with a strictly oxidative metabolism. The DNA G + C content ranged from 44 to 47 mol%. DNA-DNA hybridization experiments showed six homology groups, two of them related at the species level to the type strain of Psychrobacter immobilis, LMG 7203T (70-83%). The highest DNA relatedness of two other groups to known Psychrobacter species was found to the type strain of Psychrobacter glacincola, LMG 21282T (51-57%), and no significant similarity was found between Psychrobacter type strains and the last two groups. The predominant cellular fatty acids detected were typical of the genus Psychrobacter and included 18:1omega9c, 16:1omega7c and 17:1omega8c. 16S rRNA gene sequence analysis confirmed that the strains isolated belonged to the genus Psychrobacter. The results of the study assigned five isolates to P. immobilis, three isolates to P. glacincola and three isolates to novel Psychrobacter species. The names Psychrobacter luti sp. nov. (type strain NF11T=LMG 21276T=CECT 5885T) and Psychrobacter fozii sp. nov. (type strain NF23T=LMG 21280T=CECT 5889T) are proposed for these organisms.

Antarctic Regions↗

PubMed2006

Psychrobacter cryohalolentis sp. nov. and Psychrobacter arcticus sp. nov., isolated from Siberian permafrost.

Three Gram-negative, non-motile, non-pigmented, oxidase-positive coccobacilli capable of growth at temperatures from -10 to 30 degrees C and salinities of 0 to 1.7 M NaCl were isolated from Siberian permafrost and characterized. Both 16S rRNA and gyrB gene sequencing studies placed the isolates in the Gammaproteobacteria within the genus Psychrobacter. However, with higher bootstrap values and reproducible tree topologies, gyrB represented a more reliable phylogenetic marker for the taxonomy of Psychrobacter species. DNA-DNA hybridization data supported gyrB tree topologies and established two relatedness groups within the three isolates; neither of these groups was related at the species level to any previously described Psychrobacter species. The two groups of isolates could be differentiated phenotypically from 13 previously described Psychrobacter species using API strips. These results support the existence of two novel species of Psychrobacter, for which we propose the names Psychrobacter cryohalolentis sp. nov. (type strain K5(T) = DSM 17306(T) = VKM B-2378(T)) and Psychrobacter arcticus sp. nov. (type strain 273-4(T) = DSM 17307(T) = VKM B-2377(T)).

Cold Climate↗

PubMed2004

Psychrobacter salsus sp. nov. and Psychrobacter adeliensis sp. nov. isolated from fast ice from Adelie Land, Antarctica.

Nine psychrotolerant bacteria were isolated from fast ice in the middle of Geologie Archipelago, Adelie Land, Antarctica and were categorized into two groups, based on their SDS-PAGE profiles. Representatives from each of the two groups, namely strains DD 48T and SJ 14T exhibited phenotypic and chemotaxonomic characteristics confirming to the genus Psychrobacter. The 16S rRNA gene sequence indicated that the two isolates are closely related to each other and to the already reported fifteen species of Psychrobacter. Detailed studies on the phenotypic characteristics, chemotaxonomic properties and phylogenetic analysis of strains DD 48T and SJ 14T indicated that they are distinctly different from each other and the reported species of Psychrobacter. At the DNA-DNA hybridisation level, the two species exhibit less than 70% similarity. Thus, strains DD 48T and SJ 14T are identified as new species of the genus Psychrobacter for which the names Psychrobacter salsus sp. nov. and Psychrobacter adeliensis sp. nov. respectively are proposed.

Antarctic Regions↗

PubMed2005

Psychrobacter vallis sp. nov. and Psychrobacter aquaticus sp. nov., from Antarctica.

Twelve strains of psychrophilic bacteria were isolated from cyanobacterial mat samples collected from various water bodies in the McMurdo Dry Valley region of Antarctica. All the isolates were Gram-negative, non-motile, coccoid, psychrophilic, halotolerant bacteria and had C(16 : 1)omega7c, C(17 : 1)omega8c and C(18 : 1)omega9c as the major fatty acids, ubiquinone-8 as the respiratory quinone and DNA G+C content of 41-46 mol%. Based on these characteristics, the isolates were assigned to the genus Psychrobacter. Based on their SDS-PAGE profiles, the 12 isolates could be categorized into three groups. Six isolates of Group I were identified as representing strains of Psychrobacter okhotskensis. However, using detailed phenotypic and chemotaxonomic characteristics and phylogenetic analysis based on their 16S rRNA gene sequences, strain CMS 39(T), the only strain from Group II, and strain CMS 56(T), a representative strain of Group III, were different from each other and from all recognized species of Psychrobacter. Therefore, it is proposed to classify CMS 39(T) (=DSM 15337(T)=MTCC 4208(T)) and CMS 56(T) (=DSM 15339(T)=MTCC 4386(T)) as representing the type strains of novel species of Psychrobacter, for which the names Psychrobacter vallis sp. nov. and Psychrobacter aquaticus sp. nov., respectively, are proposed.

Antarctic Regions↗

PubMed2005

Psychrobacter aquimaris sp. nov. and Psychrobacter namhaensis sp. nov., isolated from sea water of the South Sea in Korea.

Two Gram-negative, non-motile, non-spore-forming, slightly halophilic bacterial strains, SW-210(T) and SW-242(T), were isolated from sea water of the South Sea in Korea, and were characterized taxonomically by means of a polyphasic approach. The two isolates grew optimally at 25-30 degrees C and in the presence of 2-3 % (w/v) NaCl. Strains SW-210(T) and SW-242(T) contained Q-8 as the predominant respiratory lipoquinone and C(18 : 1)omega9c as the major fatty acid. The DNA G+C contents of strains SW-210(T) and SW-242(T) were 43.2 and 45.3 mol%, respectively. The 16S rRNA gene sequences of strains SW-210(T) and SW-242(T) were 98.9 % similar, and the mean DNA-DNA relatedness value between them was 24 %. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains SW-210(T) and SW-242(T) form distinct phylogenetic lineages within the radiation of the cluster comprising Psychrobacter species, having 16S rRNA gene sequence similarity levels of 95.9-99.2 % with respect to the type strains of Psychrobacter species. The levels of DNA-DNA relatedness between the two isolates and the type strains of 15 phylogenetically related Psychrobacter species were well below 70 %. On the basis of phenotypic and phylogenetic data and genomic distinctiveness, strains SW-210(T) and SW-242(T) were classified in the genus Psychrobacter as representing two distinct novel species, for which the names Psychrobacter aquimaris sp. nov. (type strain, SW-210(T) = KCTC 12254(T) = DSM 16329(T)) and Psychrobacter namhaensis sp. nov. (type strain, SW-242(T) = KCTC 12255(T) = DSM 16330(T)) are proposed, respectively.

Base Composition↗

PubMed2002

Psychrobacter submarinus sp. nov. and Psychrobacter marincola sp. nov., psychrophilic halophiles from marine environments.

Two novel psychrophilic, halophilic, Psychrobacter-like bacteria, strains KMM 225T and KMM 277T, were isolated from sea water and the internal tissues of an ascidian Polysyncraton sp. specimen, respectively, and characterized using a polyphasic approach, which included phenotypic, genotypic, chemotaxonomic and phylogenetic analyses. The novel marine isolates were Gram-negative, aerobic, coccoid, oxidase- and catalase-positive, non-pigmented, non-motile, psychrophilic and halophilic and they utilized a restricted spectrum of carbon sources. Strains KMM 225T and KMM 277T required sea water or sodium ions for growth and were tolerant of up to 12-15% (w/v) NaCl. Growth of strains KMM 225T and KMM 277T was observed at 4-35 and 7-35 degrees C, respectively. The DNA G+C contents of KMM 225T and KMM 277T were respectively 46-8 and 50.7 mol %. Comparison of almost complete 16S rDNA sequences of strains KMM 225T and KMM 277T revealed that both strains were phylogenetically most closely related to each other (99.9% sequence similarity) and slightly less related to Psychrobacter glacincola, with 97.2 and 97.8% similarity, respectively. DNA-DNA reassociation between KMM 225T and KMM 277T revealed 15% similarity, whereas similarity to other Psychrobacter species was 14-25%. Strains KMM 225T and KMM 277T differed from one another in their growth temperature, organic substrate utilization, antibiotic sensitivity and DNA G+C content. Both strains examined could be distinguished from all previously described Psychrobacter species by their physiological, genotypic and phylogenetic characteristics. On the basis of the physiological and molecular properties of the novel isolates, the names Psychrobacter submarinus sp. nov. (type strain KMM 225T = DSM 14161T) and Psychrobacter marincola sp. nov. (type strain KMM 277T = DSM 14160T) are proposed.

Animals↗

PubMed2004

Psychrobacter maritimus sp. nov. and Psychrobacter arenosus sp. nov., isolated from coastal sea ice and sediments of the Sea of Japan.

Four strains of Gram-negative, aerobic, psychrotolerant, non-motile, non-pigmented bacteria were isolated from coastal sea-ice and sediment samples. These strains displayed the general chemotaxonomic and phenotypic features of members of the genus Psychrobacter. 16S rRNA gene sequencing positioned the three isolates KMM 3646T, KMM 3643 and KMM 3645 and isolate KMM 3659T in two distinct lineages within the genus Psychrobacter, displaying less than 98.5 % sequence similarity to the type strains of other Psychrobacter species. Genomic distinctness was supported by phenotypic differences in growth temperatures, salinity range for growth and metabolic properties. Based on a combination of phenotypic and biochemical characteristics and phylogenetic position, it is proposed that the members of these two distinct lineages represent two novel species, for which the names Psychrobacter maritimus sp. nov. (type strain Pi2-20T = KMM 3646T = DSM 15387T) and Psychrobacter arenosus sp. nov. (type strain R7T = KMM 3659T = DSM 15389T) are proposed.

Anti-Bacterial Agents↗

PubMed1996

Novel Psychrobacter species from Antarctic ornithogenic soils.

Ornithogenic soil is derived from the deposition of the fecal matter of various species of birds and is a major source of nutrient input in the Antarctic marine ecosystem. A significant proportion of microbiota of ornithogenic soil collected from an Adélie penguin colony in eastern Antarctica (Vestfold Hills ice-free zone) consisted of gram-negative, coccoid bacteria identified on the basis of their phospholipid ester-linked fatty acid and lipid class profiles as Psychrobacter strains. Phenotypic, genotypic, and 16S ribosomal DNA phylogenetic analyses revealed that the Antarctic psychrobacters belonged to three distinct groups. Comparisons with Psychrobacter immobilis and Moraxella phenylpyruvica reference cultures isolated from fish, seawater, poultry, and human clinical specimens revealed the relationships of these groups within the genus Psychrobacter. Two of the groups represent the following two novel species: Psychrobacter urativorans sp. nov. (type strain, strain ACAM 534) and Psychrobacter frigidicola sp. nov. (type strain, strain ACAM 304). The third group of strains included members of the previously described species P. immobilis (Juni and Heym 1986). In addition, M. phenylpyruvica (Bøvre and Henriksen 1967) is renamed Psychrobacter phenylpyruvicus comb. nov. (type strain, strain ACAM 535) on the basis of 16S ribosomal DNA phylogenetic data. In general, the genus Psychrobacter could be differentiated from the related genera Moraxella and Acinetobacter by the fact that the members of the genus Psychrobacter are psychrotolerant or psychrophilic and halotolerant, which reflects the ubiquitous distribution of the genus in both marine and terrestrial environments. On the basis of the results of this and previous studies, the genus Psychrobacter is the predominant genus in ornithogenic soils in Antarctica and is diverse.

Antarctic Regions↗

PubMed2003

Psychrobacter pulmonis sp. nov., isolated from the lungs of lambs.

Unusual Gram-negative, catalase- and oxidase-positive, coccus-shaped bacteria isolated from the lungs of two lambs were characterized by phenotypic and molecular-genetic methods. Comparative 16S rRNA gene sequencing studies demonstrated that the unknown isolates were genealogically highly related to each other (99.8% sequence similarity) and represent a novel subline within the genus Psychrobacter. The unknown bacterium was phylogenetically closely related to, but distinct from, Psychrobacter phenylpyruvicus, Psychrobacter immobilis, Psychrobacter glacincola and Psychrobacter urativorans. The novel Psychrobacter isolates were readily distinguished from all other Psychrobacter species and other Gram-negative, oxidase-positive bacteria usually responsible for lung infections in sheep by physiological and biochemical tests. Based on molecular-genetic and phenotypic evidence, it is proposed that the unknown Psychrobacter isolates from lambs be classified as Psychrobacter pulmonis sp. nov. The type strain is strain S-606T (=CECT 5989T =CCUG 46240T).

Animals↗

PubMed2001

Psychrobacter proteolyticus sp. nov., a psychrotrophic, halotolerant bacterium isolated from the Antarctic krill Euphausia superba Dana, excreting a cold-adapted metalloprotease.

An Antarctic marine bacterium (strain 116) excreting an extracellular cold-adapted metalloprotease was subjected to a detailed polyphasic taxonomic investigation. Strain 116 was previously isolated from the stomach of a specimen of the Antarctic krill Euphasia superba Dana and tentatively characterized as Sphingomonas paucimobilis 116. The 16S rDNA sequence analysis showed that the strain is in fact related to species of the genus Psychrobacter, next to Psychrobacter glacincola (97.4% similarity). Sequence similarities between strain 116 and other Psychrobacter species ranged from 96.9% (with P. urativorans) to 95.4% (with P. immobilis). Key phenotypic characteristics as well as chemotaxonomic features of the bacterium were congruent with the description of the genus Psychrobacter i.e. cells were strictly aerobic, strongly oxidase-positive, psychrotrophic, halotolerant, gram-negative non-motile coccobacilli, with ubiquinone-8 as the main respiratory lipoquinone and 18:1 cis 9, 16:1 cis and 17:1 (omega8c being the predominant cellular fatty acids. The G+C content of the DNA was 43.6 mol%. DNA-DNA hybridization studies showed that the relatedness between strain 116 and Psychrobacter glacinola is only 62.2%. Further differences were apparent in whole-cell SDS-PAGE protein pattern, cellular fatty acid profile and in a number of physiological and biochemical characteristics as well as in enzymatic activities. Tolerance to 5% bile salts, nitrate reduction, citrate utilization, acid production from carbohydrates, alkaline phosphatase, acid phosphatase, C4 esterase, C14 lipase and valine arylamidase were found to differentiate strain 116 from Psychrobacter glacincola. On the basis of this phenotypic and molecular evidences, strain 116, previously known as Sphingomonas paucimobilis 116, was recognized as a new species of the genus Psychrobacter for which the name Psychrobacter proteolyticus is proposed. Strain 116 has been deposited in the Collection de l'Institut Pasteur, France, as CIP106830T and in the Deutsche Sammlung von Mikroorganismen and Zellkulturen, as DSM13887.

Adaptation, Biological↗

PubMed2005

Incidence, radioresistance, and behavior of Psychrobacter spp. in rabbit meat.

The relative incidence of Psychrobacter spp. in rabbit meat, the radioresistance of these bacteria, and the growth of nonirradiated and irradiated psychrobacter isolates, alone and in coculture, during chilled storage of inoculated sterile rabbit meat was investigated. Psychrobacter spp. accounted for 4.2% of the storage psychrotrophic flora of 30 rabbit carcasses. The radiation D10-values of 10 Psychrobacter isolates, irradiated at 4 degrees C in minced rabbit meat, ranged from 0.8 to 2.0 kGy, with significant (P < 0.05) differences among strains. Over 12 days of storage at 4 degrees C, pure cultures of two nonirradiated psychrobacter strains (D10 = 2 kGy) were capable of substantial increases (up to 3 log CFU/g) in sterile rabbit meat, but when the fastest growing strain was cocultured with Pseudomonas fluorescens and Brochothrix thermosphacta isolates, maximum cell densities and growth rates were significantly (P < 0.01) lower. After irradiation (2.5 kGy) of pure cultures in sterile rabbit meat, surviving cells of both Psychrobacter strains decreased for a period of 5 to 7 days and then resumed multiplication that, at day 12, resulted in a similar increase (1.6 to 1.7 log CFU/g) over initial survivor numbers. When irradiated in combination with the spoilage bacteria, one of the strains required 12 days to reach initial numbers. In conclusion, Psychrobacter spp. are radioresistant nonsporeforming bacteria with a low relative incidence among the storage flora of rabbit meat, unable to compete with food spoilage bacteria in this ecosystem and apparently not a major contributor to the spoilage of rabbit meat after irradiation.

Animals↗

PubMed2000

Psychrobacters and related bacteria in freshwater fish.

Three phenotypic identification systems were employed to identify 106 strains of gram-negative, nonmotile, aerobic bacteria obtained during iced storage of wild (Salmo trutta and Esox lucius) and farmed (Oncorhynchus mykiss) freshwater fish. Using diagnostic tables and computer-assisted identification, the isolates were Psychrobacter (64 strains), Acinetobacter (24 strains), Moraxella (6 strains), Chryseobacterium (5 strains), Myroides odoratus (2 strains), Flavobacterium (1 strain), Empedobacter (1 strain), and unidentified (3 strains). Overall similarities of all strains were determined for 108 characters by numerical analysis (simple matching coefficient of similarity [S] and clustering by unweighted pair group average linkage [UPGMA]). At the 77% similarity level, 92 strains formed nine major clusters (3 or more strains) and four small clusters (2 strains). Cluster 1 (25 isolates divided into two main subclusters) could be assigned to Psychrobacter phenylpyruvicus, clusters 2 and 3 (26 isolates) were designated as Psychrobacter immobilis, and clusters 4 (3 isolates) and 7 (4 isolates) were identified as Psychrobacter urativorans and Psychrobacter spp., respectively. Clusters 5 (five isolates), 6 (three isolates), and 9 (five isolates) were labeled as Acinetobacter spp., Acinetobacter johnsonii, and Acinetobacter lwoffii, respectively. Cluster 8 (12 isolates), with a high resemblance to Thornley's phenon 4 (a heterogeneous group of bacteria isolated from poultry and related to Acinetobacter), remained unnamed. The restriction pattern was identical for strains grouped into clusters 2 and 3 (P. immobilis) but was different for the remaining Psychrobacter isolates. A large proportion of isolates belonging to the family Moraxellaceae were closely related. Psychrobacters and A. johnsonii were present in freshly caught fish and river water. In the latter stages of storage, P. phenylpyruvicus and acinetobacters tended to decrease, whereas P. immobilis increased.

Animals↗

PubMed2003

Psychrobacter jeotgali sp. nov., isolated from jeotgal, a traditional Korean fermented seafood.

Two Gram-negative, non-motile, non-spore-forming and moderately halophilic cocci (strains YKJ-103T and YKJ-105) were isolated from the traditional Korean fermented seafood, jeotgal. The two strains grew optimally at 25-30 degrees C and grew at 4 and 36 degrees C, but not above 37 degrees C. They grew in the presence of 0-10% (w/v) NaCl with an optimum of 2-3% (w/v) NaCl. Strains YKJ-103T and YKJ-105 were chemotaxonomically characterized by having ubiquinone-8 (0-8) as the predominant isoprenoid quinone and C18:1omega9c as the major fatty acid. The polar lipid analysis indicated the presence of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The DNA G + C contents of strains YKJ-103T and YKJ-105 were 44 and 43 mol%, respectively. Strains YKJ-103T and YKJ-105 showed no difference in their 16S rDNA sequences, and their mean level of DNA-DNA relatedness was 92.3%. Phylogenetic analysis based on 16S rDNA sequences showed that the two strains form a distinct phylogenetic lineage within the cluster comprising Psychrobacter species. Strains YKJ-103T and YKJ-105 exhibited 16S rDNA similarities of 96.6% with the type strain of Psychrobacter proteolyticus, the closest Psychrobacter species, and of 94.5-95.9% with type strains of other Psychrobacter species. On the basis of phenotypic properties, phylogenetic and genomic data, strains YKJ-103T and YKJ-105 should be placed in the genus Psychrobacter as members of a new species, for which the name Psychrobacter jeotgali sp. nov. is proposed. The type strain of the new species is strain YKJ-103T (=KCCM 41559T = JCM 11463T).

Base Composition↗

PubMed2005

Psychrobacter alimentarius sp. nov., isolated from squid jeotgal, a traditional Korean fermented seafood.

Two Gram-negative, non-motile, non-spore-forming, moderately halophilic strains, JG-100T and JG-102, were isolated from squid jeotgal, a traditional Korean fermented seafood. The two strains grew optimally at 30 degrees C and in the presence of 2-3 % (v/w) NaCl. Strains JG-100T and JG-102 were characterized chemotaxonomically; they both had ubiquinone-8 as the predominant respiratory lipoquinone and C(18 : 1)omega9c as the major fatty acid. Their DNA G+C content was 44 mol%. Strains JG-100T and JG-102 showed 1 bp difference in their 16S rRNA gene sequences and a mean DNA-DNA relatedness level of 88 %. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains JG-100T and JG-102 form a distinct phylogenetic lineage within the cluster comprising Psychrobacter species. The 16S rRNA gene sequences of strains JG-100T and JG-102 had similarity levels of 95.2-98.4 % to sequences of the type strains of recognized Psychrobacter species. Levels of DNA-DNA relatedness between strains JG-100T and JG-102 and the type strains of some phylogenetically related Psychrobacter species were 6-24 %. On the basis of phenotypic and phylogenetic data and genomic distinctiveness, strains JG-100T and JG-102 should be placed in the genus Psychrobacter as a novel species, for which the name Psychrobacter alimentarius sp. nov. (type strain, JG-100T=KCTC 12186T=DSM 16065T) is proposed.

Animals↗

PubMed2005

Psychrobacter cibarius sp. nov., isolated from jeotgal, a traditional Korean fermented seafood.

Two novel Psychrobacter-like bacterial strains, JG-219(T) and JG-220, were isolated from jeotgal, a traditional Korean fermented seafood. Cells of strains JG-219(T) and JG-220 were Gram-negative, non-motile coccobacilli. Growth of the two strains was observed at 4-32 degrees C. They grew optimally in the presence of 2-5 % (w/v) NaCl. Strains JG-219(T) and JG-220 contained C(18 : 1)omega9c and C(17 : 1)omega8c as the major fatty acids and Q-8 as the predominant ubiquinone. The DNA G+C contents of strains JG-219(T) and JG-220 were 43.5 and 43.0 mol%, respectively. The two strains showed no difference in their 16S rRNA gene sequences but exhibited minor differences in their phenotypic properties. Strains JG-219(T) and JG-220 exhibited levels of 16S rRNA gene sequence similarity of 95.2-98.7 % to the type strains of recognized Psychrobacter species. The mean level of DNA-DNA relatedness between strains JG-219(T) and JG-220 was 84.4 %. The two strains exhibited levels of DNA-DNA relatedness of 1.5-32.9 % to the type strains of eight phylogenetically related Psychrobacter species. On the basis of phenotypic data and phylogenetic and genetic distinctiveness, the two strains were classified as representing a novel species within the genus Psychrobacter, Psychrobacter cibarius sp. nov. The type strain is JG-219(T) (=KCTC 12256(T)=DSM 16327(T)).

Bacterial Typing Techniques↗

PubMed2005

Psychrobacter celer sp. nov., isolated from sea water of the South Sea in Korea.

A Gram-negative, non-motile, non-spore-forming, slightly halophilic bacterial strain, SW-238(T), was isolated from sea water collected from the South Sea in Korea, and subjected to a polyphasic taxonomic study. The organism grew optimally at 25-30 degrees C and in the presence of 2-3% (w/v) NaCl. Strain SW-238(T) was characterized chemotaxonomically as containing ubiquinone (Q-8) as the predominant respiratory lipoquinone and C(18:1)omega9c as the major fatty acid. Its DNA G+C content was 47.6 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain SW-238(T) fell within the radiation of the cluster comprising Psychrobacter species. The 16S rRNA gene sequence of strain SW-238(T) had similarity levels of 94.8-97.9% to sequences of the type strains of recognized Psychrobacter species. Levels of DNA-DNA relatedness between strain SW-238(T) and the type strains of 10 phylogenetically related Psychrobacter species were below 70%. On the basis of phenotypic and phylogenetic data and genetic distinctiveness, strain SW-238(T) (=KCTC 12313(T)=JCM 12601(T)) was placed in the genus Psychrobacter as the type strain of a novel species, for which the name Psychrobacter celer sp. nov. is proposed.

Bacterial Typing Techniques↗

PubMed2000

Phylogenetic analysis of psychrophilic bacteria isolated from the Japan Trench, including a description of the deep-sea species Psychrobacter pacificensis sp. nov.

Phylogenetic positions of psychrophilic bacteria isolated from the Japan Trench were determined by sequencing analysis of PCR-amplified bacterial small subunit (16S) rRNA genes. Between surface and deep-sea psychrophiles, distinct positions clearly differed within the gamma-Proteobacteria. In phylogenetic analysis using neighbour-joining, maximum-parsimony and maximum-likelihood, strains from surface seawater were inferred to be located in the Halomonas aquamarina-meridiana clade within the family Halomonadaceae. Strains from deep seawater (5000-6000 m), however, formed a novel monophyletic clade within the Moraxella-Psychrobacter branch in the family Moraxellaceae, showing separation from terrestrial and Antarctic relatives. These deep-sea strains were also discriminated from other known Psychrobacter species in phenotype, e.g. limited growth in the absence of NaCl (optimum at about 3% NaCl), positive urease activity, acid production from xylose and arabinose, and the presence of multiple fimbriae. DNA relatedness values among six deep-sea strains were > 85% in DNA-DNA hybridization experiments and > 98% in aligned 16S rDNA sequences. From this evidence, a new species, Psychrobacter pacificensis, is proposed for these deep-sea psychrophiles; the type strain of Psychrobacter pacificensis is strain NIBH P2K6T (= IFO 16270T). Occurrence of psychrobacters in cold Japan Trench deep seawater and at the Antarctic sea surface suggests that deep-sea bacterial habitation and evolution have been mediated by global deep-ocean circulation linked to the sinking of cooled seawater in polar regions.

Cold Temperature↗

PubMed2002

Psychrobacter faecalis sp. nov., a new species from a bioaerosol originating from pigeon faeces.

The taxonomy of strain Iso-46T isolated from a bioaerosol generated by cleaning of a pigeon faeces contaminated room was investigated in a polyphasic approach. The beige pigmented Gram-negative, oxidase-negative organism contained a quinone system with mainly ubiquinone Q-8, and the polar lipid profile was composed of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol, beside some hitherto uncharacterized phospholipids. Major polyamines were spermidine and putrescine and also small amounts of cadaverine. The analysis of the fatty acids revealed 3-OH 12:0 and 3-OH 14:0 (within summed feature 3) as hydroxylated fatty acids. These chemotaxonomic characteristics suggest that the strain belongs to the gamma-subclass of the Proteobacteria namely into the genus Psychrobacter. Analysis of the 16S rRNA gene supported the allocation into the genus Psychrobacter, but showing similarities to all described species of this genus lower than 97%. Iso-46T was able to grow on MacConkey agar and other high nutrient containing media within a temperature range of 4 degrees C to 36 degrees C. On the basis of nutritional and further physiological features, a clear differentiation from all other Psychrobacter species was possible. For these reasons it is proposed to create a new species with the name Psychrobacter faecalis sp. nov.

Aerosols↗