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PubMedDate not supplied

[Methanotrophic bacteria of acid sphagnum bogs].

Acid sphagnum bogs cover a considerable part of the territory of Russia and are an important natural source of biogenic methane, which is formed in their anaerobic layers. A considerable portion of this methane is consumed in the aerobic part of the bog profile by acidophilic methanotrophic bacteria, which comprise the methane filter of sphagnum bogs and decrease CH4 emission to the atmosphere. For a long time, these bacteria escaped isolation, which became possible only after the elucidation of the optimal conditions of their functioning in situ: pH 4.5 to 5.5; temperature, from 15 to 20 degrees C; and low salt concentration in the solution. Reproduction of these conditions and rejection of earlier used media with a high content of biogenic elements allowed methanotrophic bacteria of two new genera and species--Methylocella palustris and Methylocapsa acidophila--to be isolated from the peat of sphagnum bogs of the northern part of European Russia and West Siberia. These bacteria are well adapted to the conditions in cold, acid, oligotrophic sphagnum bogs. They grow in a pH range of 4.2-7.5 with an optimum at 5.0-5.5, prefer moderate temperatures (15-25 degrees C) and media with a low content of mineral salts (200-500 mg/l), and are capable of active nitrogen fixation. Design of fluorescently labeled 16S rRNA-targeted oligonucleotide probes for the detection of Methylocella palustris and Methylocapsa acidophila and their application to the analysis of sphagnum peat samples showed that these bacteria represent dominant populations of methanotrophs with a density of 10(5)-10(6) cells/g peat. In addition to Methylocella and Methylocapsa populations, one more abundant population of methanotrophs was revealed (10(6) cells/g peat), which were phylogenetically close to the genus Methylocystis.

Alphaproteobacteria↗
PubMed2006

[Diversity of halophilic archaea in hypersaline lakes of Inner Mongolia, China].

The aims of this work were to explore the diversity of halophilic archaea in hypersaline lakes of Inner Mongolia, China and to collect novel halophilic archaea. One hundred and sixty-five halophilic archaea were isolated from the three different types of hypersaline lakes (Erliannor, shangmatala and Xilin soda lake) in Inner Mongolia. By analysis of the restriction patterns of amplified 16S rDNA (ARDRA) with the enzyme Afa I and Hae II, respectively, the isolates were clustered into 14 genotypes, and the representatives of each genotype were randomly chosen for the determination of 16S rDNA sequence. The phylogenetic analysis revealed that all of the isolates were clustered into 10 groups: Halorubrum, Natronococcus, Natronorubrum, Haloterrigena, Halorhabdus, Halobiforma, Haloarcula, Haloferax and other two unknown groups. Dominant isolates were related to Halorubrum spp. in all three lakes. Some of the isolates studied showed less affiliation with known taxa ( <98% sequence similarity) and may represent novel taxa. Two isolates HXH33 and HSH33 showed very less affiliation with known genus ( < 93% sequence similarity) and may represent two new genera. These results suggest that diverse archaea exist in and the unknown archaea thrive in the hypersaline lakes of Inner Mongolia.

Biodiversity↗
PubMed2006

[Analysis of DNA homology and 16S rDNA sequence of rhizobia, a new phenotypic subgroup, isolated from Xizang Autonomous Region of China].

Based on the studies of numerical taxonomy, the seven rhizobial strains isolated from the root nodules of leguminous plants Trigonella spp. and Astragalus spp. growing in the Xizang Autonomous Region of China constituted a new phenotypic subgroup, where wide phenotypic and genotypic diversity among legume crops had been reported due to complex terrain and various climate. The new phenotypic subgroup were further identified to clarify its taxonomic position by DNA homology analysis and 16S rDNA gene sequencing. The mol% G + C ratio of the DNA among members of the new subgroup ranged from 59.5 to 63.3 mol% as determined by T (m) assay. The levels of DNA relatedness, determined by using the DNA liquid hybridization method, among the members of the new subgroup were between 74.3% and 92.3%, while level of DNA relatedness between the central strains XZ2-3 of the new subgroup and the type strains of known species of Rhizobium was less than 47.4%. These results indicated that the new phenotypic subgroup is a DNA homological group different from described species of Rhizobium. Therefore, this new phenotypic subgroup was supposed to be a new species in the genus of Rhizobium since the strains in the same species generally exhibit levels of DNA homology ranging from 70 to 100%. A systematic identification method-16S rDNA gene sequence comparison was carried out to determine the phylogenetic relationships of the new subgroup with the described species of Rhizobium. The GenBank accession number for the 16S rDNA sequence of the central strain XZ2-3 of the new subgroup is DQ099745. The full-length 16S rDNA gene sequence were sequenced by chain terminator techniques and analyzed with PHYLIP. The phylogenetic trees were constructed by using the programs DRAWTREE. The phylogenetic analysis indicated that new subgroup occupy a independent sub-branch in phylogenetic tree. The sequence similarities between the center strain XZ2-3 and the closest relatives, strain R. leguminosarum USDA2370T and R. etli CFN42T, were 96.55% and 96.62% respectively. Both the 16S rDNA sequence data and the DNA relatedness data suggested that the new phenotypic subgroup isolated from the root nodules of leguminous plants Trigonella spp. and Astragalus spp. obtained from the Xizang Autonomous Region of China represents a new rhizobial species in the genus of Rhizobium according to the minimal standards for the description of new genera and species of root-and stem-nodulating bacteria.

Base Sequence↗
PubMed1994

New species of mites (Acari, Astigmata, Canestriniidae) associated with Lucanidae, Carabidae and Scarabaeidae (Insecta, Coleoptera).

New species associated with Coleoptera are described: Sandrophela hugoni from Sumatra, S. sophiae from India, S. amarae from Java and Sumatra, Dicanestrinia huberti, Photia adolfinae both from Poland, Scarabiphotia vigoni from unknown locality, Beeriphotia volkeri, Canestrinia paavoi and C. ramoni, all from China. There are created two new genera: Beeriphotia and Scarabiphotia.

Animals↗
PubMedDate not supplied

[Approaches to classifying bifidobacteria based on DNA structural data].

A brief historical review of classifications of Bifidobacteria demonstrates the difficulties in this problem, for the present-day classifications are far from being satisfactory. Based on the genotypical heterogeneity of the genus Bifidobacterium, the authors validate the possibility of raising it to the status of the family Bidobacteriaceae fam. nov. The principle of forming new genera within the frames of this hypothetical family, discussed in the paper, originates from the genomic similarity of representatives of some species of this group of microorganisms.

Bifidobacterium↗
PubMedDate not supplied

[One classification of the monogeneans of the Microcotylidae family].

The division of the family Microcotylidae suggested by Unnithan, 1971 into subordinate taxons is quite unsatisfactory. A detailed analysis has shown that all the subfamilies erected by Unnithan due to some reasons or others are invalid. Of 13 new genera six are synonyms of other earlier known genera, one is nomen preoccupatum, one genus is doubtful and only five genera are valid. However, three genera of these five need a serious revision since they represent a conglomerate of non-allied species and one genus requires some emmendations.

Animals↗
PubMed1996

Anaerobic cocci of clinical importance.

The current knowledge is reviewed concerning the anaerobic cocci, in particular those of clinical relevance. The anaerobic cocci are defined and their current taxonomic positions discussed. It is clear that new genera and species await to be characterised fully. The overwhelming majority found in clinical material belong to the genus Peptostreptococcus, with the remainder belonging to the veillonellae and, possibly, ruminococci. Human infections with other anaerobic cocci are extremely rare. Their morphology, metabolism and culture, and role in clinical infections are assessed. The methods for isolation and identification, which for some species are difficult, are presented, together with brief summaries of the clinically important species. The review concludes with the current status of antibiotic susceptibilities and the methods used to test susceptibility in vitro. There is no current consensus as to which susceptibility test method is the method of choice.

Gram-Negative Anaerobic Cocci↗
PubMed2005

A survey on bacteria inhabiting the sea surface microlayer of coastal ecosystems.

Bacterial populations inhabiting the sea surface microlayer from two contrasted Mediterranean coastal stations (polluted vs. oligotrophic) were examined by culturing and genetic fingerprinting methods and were compared with those of underlying waters (50 cm depth), for a period of two years. More than 30 samples were examined and 487 strains were isolated and screened. Proteobacteria were consistently more abundant in the collection from the pristine environment whereas Gram-positive bacteria (i.e., Actinobacteria and Firmicutes) were more abundant in the polluted site. Cythophaga-Flavobacter-Bacteroides (CFB) ranged from 8% to 16% of total strains. Overall, 22.5% of the strains showed a 16S rRNA gene sequence similarity only at the genus level with previously reported bacterial species and around 10.5% of the strains showed similarities in 16S rRNA sequence below 93% with reported species. The CFB group contained the highest proportion of unknown species, but these also included Alpha- and Gammaproteobacteria. Such low similarity values showed that we were able to culture new marine genera and possibly new families, indicating that the sea-surface layer is a poorly understood microbial environment and may represent a natural source of new microorganisms. Genetic fingerprinting showed, however, no consistent differences between the predominant bacterial assemblages from surface microlayer and underlying waters, suggesting that the presence of a stable and abundant neustonic bacterial community is not a common trait of coastal marine environments.

Bacteria↗
PubMed2000

Two unusual new dinoflagellate cyst genera from the Bunde Borehole, Maastrichtian type area, southern Netherlands.

Maastrichtian and Danian deposits from the Bunde Borehole in the Maastrichtian type area contain the morphologically unusual dinoflagellate species Spumadinium felderorum gen. et sp. nov. and Lasagniella herngreenii gen. et sp. nov., both of which have archeopyles formed by the loss of several paraplates. In S. felderorum the paraplates forming the operculum or opercular pieces appear to be the third and fourth precingulars (3"-4") plus the first and second anterior intercalaries (1a-2a). This suggests that Spumadinium, although having a wall resembling some cribroperidinioids, is a cladopyxiinean. L. herngreenii is unique in having up to eight wall layers, separated and supported by buttresses. The archeopyle is also a combination type but formed by loss of one apical (3'), three anterior intercalary (1a-3a) and three precingular (3"-5") paraplates. Thus, Lasagniella is assignable to the Peridiniales. The distinctive morphology and restricted ranges of the two genera make them useful stratigraphic markers for the Upper Maastrichtian-Danian.

Journal Article↗
PubMed2005

[Influence of Professor Konstanty Janicki's discoveries on progress in protistology].

Professor Konstanty Janicki published 11 protozoological papers. They concern the flagellate parasites of cockroaches and termites, as well as the amebas parasitising cockroaches and chaetognaths. He described the morphology and cytology of 12 species of flagellates, including 4 new species and genera. Three new species parasitising termites belong to the Parabasalia, one--Oxymonas granulosa, without the Golgi apparatus, initiated a new group of protista, the Oxymonadida Grassé, 1952. Konstanty Janicki also examined some important questions dealing with protozoology such as: (1) Karyomastigont. Janicki analysed the connection of the cell nucleus to the mastigont system in flagellates from termites and cockroaches. Also he described the replication of karyomastigonts of some species. This organelle plays an important part in the discussions on evolution of the lower Protista. (2) Parabasal apparatus. Janicki described the parabasal body in flagellates from cockroaches and termites, paying special attention to its peculiarities. This organelle was later named: "Janicki-type parabasal apparatus" and together with pleuromitosis became the main characters of an independent group of protista--Parabasalia. (3) Parasome. Konstanty Janicki also studied the enigmatic body (parasome, Nebenkörper), near the cell nucleus and staining like it, in amebas from the genus Paramoeba. He described this body dividing. After TEM investigation of Janickina (=Paramoeba) pigmentifera, this body is presently recognized as an endosymbiotic flagellate. Summing up, it may be stated that all findings of Professor Konstanty Janicki were the object of further investigations and occupy an important place in protistology.

Animals↗
PubMedDate not supplied

Nature, nomenclature and taxonomy of obligate methanol utilizing strains.

In a screening program, a number of different bacterial strains with the ability to utilize methanol as a sole carbon and energy source were isolated and described. They are well known methanol utilizing genera Pseudomonas, Klebsiella, Micrococcus, Methylomonas or, on the contrary, the new, unknown genera and species of methylotrophic bacteria. In the last category, Acinetobacter and Alcaligenes are the new reported genera of organisms able to use methanol as a sole carbon and energy source. The present paper reports the very complex physiological and biochemical modifications when very versatile bacteria such as Pseudomonas aeruginosa and Acinetobacter calcoaceticus are cultured on methanol and when the obligate methylotrophic state is compared with the facultative methylotrophic state of the same bacterial strain. Based on experiments and comparisons with literature data, it seems that Methylomonas methanica is the obligate methylotrophic state of Pseudomonas aeruginosa and that Acinetobacter calcoaceticus is the facultative methylotrophic state of Methylococcus capsulatus, an obligate methylotroph. The relationship of the obligate to the facultative and of the facultative to the obligate methylotrophy were established. These new methylotrophic genera and species, the profound physiological and biochemical modifications as well as the new data concerning nature, nomenclature and taxonomy of methanol utilizing bateria were reported for the first time in 1983.

Animals↗
PubMed2002

Gymnomeropsylla n. gen. (Siphonaptera: Pygiopsyllidae) from Sulawesi, Indonesia, with the description of two new species.

Compared to related genera, this new flea genus is characterized by the absence, or presence of very few, bristles on the external surface of femur I and especially by the morphology of the apex of sternite IX in the male, which is hyaline and lacks spiniform bristles. The two new species, G. bunomydis and G. margaretamydis, are distinguished from each other by the structure of the genitalia, and the presence of numerous erect bristles on the thorax and abdominal tergites of the latter species. Both of these new species parasitize murine rodents that are endemic to Sulawesi; G. bunomydis was collected mainly from Bunomys chrysocomus and G. margaretamydis only from Margaretamys parvus.

Animals↗
PubMed1968

Prosthecomicrobium and Ancalomicrobium: new prosthecate freshwater bacteria.

Direct microscopic examination of natural freshwater samples reveals a variety of small microorganisms having elaborate cellular appendages. Several strains have been isolated from crude cultures containing low concentrations of organic nutrients. All of the isolates are procaryotic. They are aerobic chemoorganotrophs that require vitamins for growth. Because they cannot be assigned to any of the existing bacterial genera, two new genera are proposed: Ancalomicrobium for organisms which have several long appendages and which reproduce by budding; Prosthecomicrobium for organisms which have many short appendages tapering toward a blunt tip and which reproduce by binary fission. Gas vacuoles have been found in strains of each genus. The term prostheca is proposed for the rigid appendages of procaryotic cells bounded by the cell wall, and is defined to include the structures on these new bacteria, as well as the stalks of the caulobacters and the hyphae of the hyphomicrobia.

Bacteria↗