scholarly journals Glaciochemistry and pigment producing ability of bacteria from roof of the world, the glaciers of Karakoram, Pakistan

2021 ◽  
Author(s):  
Noor Hassan ◽  
Muhammad Rafiq ◽  
Abdul Haleem ◽  
Aamir Ali Shah ◽  
Fariha Hasan
Keyword(s):  
Bacterial Species ◽  
Rpob Gene ◽  
Mountain Range ◽  
Bacterial Strains ◽  
Mountain Ranges ◽  
The World ◽  
Alternative Sources ◽  
Geochemical Analyses ◽  
Pigmented Bacteria

Abstract The Karakoram Mountain Range (KMR) is one of the largest mountain ranges in the world, with ~ 37% of its area glaciated. Here, we present the geochemistry of ice, sediment and meltwaters sampled from Ghulmet, Ghulkin and Hopar glaciers of the Karakoram Range, Pakistan, in addition to the first information on the diversity of pigmented bacteria evaluated using culture-dependent techniques. Geochemical analyses revealed Ca2+ and SO42− to be the most abundant cation and anion species across all glacial samples, respectively. Total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) were found in the sediments of all glaciers studied in current research. Bacterial species were capable of producing a variety of different pigments, including alloxanthin, astaxanthin, bacterioruberin, β-carotene, 19'-hexanoyloxyfucoxanthin, peridinin, violacein and zeaxanthin. Culturable bacterial diversity was studied using two molecular biomarkers, 16S rRNA and rpoB gene, with a total of 82 bacterial strains representing 25 genera identified across all glacial samples. This study provides the first characterization of glacier-associated, pigment-producing bacterial communities from the KMR. Findings are important for considerations of alternative sources of conventional pigment production in industrial fields.

scholarly journals The Expanded Universe of Prokaryotic Argonaute Proteins

mBio ◽  
2018 ◽  
Vol 9 (6) ◽  
Author(s):  
Sergei Ryazansky ◽  
Andrey Kulbachinskiy ◽  
Alexei A. Aravin
Keyword(s):  
Rna Interference ◽  
Nucleic Acid ◽  
Genome Engineering ◽  
Bacterial Species ◽  
Host Cells ◽  
Bacterial Strains ◽  
Domains Of Life ◽  
Genomic Studies ◽  
Basic Biology

ABSTRACT Members of the ancient family of Argonaute (Ago) proteins are present in all domains of life. The common feature of Ago proteins is the ability to bind small nucleic acid guides and use them for sequence-specific recognition—and sometimes cleavage—of complementary targets. While eukaryotic Ago (eAgo) proteins are key players in RNA interference and related pathways, the properties and functions of these proteins in archaeal and bacterial species have just started to emerge. We undertook comprehensive exploration of prokaryotic Ago (pAgo) proteins in sequenced genomes and revealed their striking diversity in comparison with eAgos. Many pAgos contain divergent variants of the conserved domains involved in interactions with nucleic acids, while having extra domains that are absent in eAgos, suggesting that they might have unusual specificities in the nucleic acid recognition and cleavage. Many pAgos are associated with putative nucleases, helicases, and DNA binding proteins in the same gene or operon, suggesting that they are involved in target processing. The great variability of pAgos revealed by our analysis opens new ways for exploration of their functions in host cells and for their use as potential tools in genome editing. IMPORTANCE The eukaryotic Ago proteins and the RNA interference pathways they are involved in are widely used as a powerful tool in research and as potential therapeutics. In contrast, the properties and functions of prokaryotic Ago (pAgo) proteins have remained poorly understood. Understanding the diversity and functions of pAgos holds a huge potential for discovery of new cellular pathways and novel tools for genome manipulations. Only few pAgos have been characterized by structural or biochemical approaches, while previous genomic studies discovered about 300 proteins in archaeal and eubacterial genomes. Since that time the number of bacterial strains with sequenced genomes has greatly expanded, and many previously sequenced genomes have been revised. We undertook comprehensive analysis of pAgo proteins in sequenced genomes and almost tripled the number of known genes of this family. Our research thus forms a foundation for further experimental characterization of pAgo functions that will be important for understanding of the basic biology of these proteins and their adoption as a potential tool for genome engineering in the future.

scholarly journals Characterization of gtf, a Glucosyltransferase Gene in the Genomes of Pediococcus parvulus and Oenococcus oeni, Two Bacterial Species Commonly Found in Wine

2008 ◽  
Vol 74 (13) ◽  
pp. 4079-4090 ◽  
Author(s):  
Marguerite Dols-Lafargue ◽  
Hyo Young Lee ◽  
Claire Le Marrec ◽  
Alain Heyraud ◽  
Gérard Chambat ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Oenococcus Oeni ◽  
Mobile Elements ◽  
The Other ◽  
Bacterial Strains ◽  
Model Medium ◽  
Polysaccharide Synthesis

ABSTRACT “Ropiness” is a bacterial alteration in wines, beers, and ciders, caused by β-glucan-synthesizing pediococci. A single glucosyltransferase, Gtf, controls ropy polysaccharide synthesis. In this study, we show that the corresponding gtf gene is also present on the chromosomes of several strains of Oenococcus oeni isolated from nonropy wines. gtf is surrounded by mobile elements that may be implicated in its integration into the chromosome of O. oeni. gtf is expressed in all the gtf + strains, and β-glucan is detected in the majority of these strains. Part of this β-glucan accumulates around the cells forming a capsule, while the other part is liberated into the medium together with heteropolysaccharides. Most of the time, this polymer excretion does not lead to ropiness in a model medium. In addition, we show that wild or recombinant bacterial strains harboring a functional gtf gene (gtf +) are more resistant to several stresses occurring in wine (alcohol, pH, and SO2) and exhibit increased adhesion capacities compared to their gtf mutant variants.

scholarly journals Regulation of Hypercompetence in Legionella pneumophila

2004 ◽  
Vol 186 (12) ◽  
pp. 3814-3825 ◽  
Author(s):  
Jessica A. Sexton ◽  
Joseph P. Vogel
Keyword(s):  
Legionella Pneumophila ◽  
Bacterial Species ◽  
Single Species ◽  
Great Promise ◽  
Dna Uptake ◽  
Bacterial Strains ◽  
Aerobic Growth ◽  
Laboratory Conditions ◽  
Normal Laboratory

ABSTRACT Although many bacteria are known to be naturally competent for DNA uptake, this ability varies dramatically between species and even within a single species, some isolates display high levels of competence while others seem to be completely nontransformable. Surprisingly, many nontransformable bacterial strains appear to encode components necessary for DNA uptake. We believe that many such strains are actually competent but that this ability has been overlooked because standard laboratory conditions are inappropriate for competence induction. For example, most strains of the gram-negative bacterium Legionella pneumophila are not competent under normal laboratory conditions of aerobic growth at 37°C. However, it was previously reported that microaerophilic growth at 37°C allows L. pneumophila serogroup 1 strain AA100 to be naturally transformed. Here we report that another L. pneumophila serogroup 1 strain, Lp02, can also be transformed under these conditions. Moreover, Lp02 can be induced to high levels of competence by a second set of conditions, aerobic growth at 30°C. In contrast to Lp02, AA100 is only minimally transformable at 30°C, indicating that Lp02 is hypercompetent under these conditions. To identify potential causes of hypercompetence, we isolated mutants of AA100 that exhibited enhanced DNA uptake. Characterization of these mutants revealed two genes, proQ and comR, that are involved in regulating competence in L. pneumophila. This approach, involving the isolation of hypercompetent mutants, shows great promise as a method for identifying natural transformation in bacterial species previously thought to be nontransformable.

scholarly journals Characterization of Phascolarctobacterium succinatutens sp. nov., an Asaccharolytic, Succinate-Utilizing Bacterium Isolated from Human Feces

2011 ◽  
Vol 78 (2) ◽  
pp. 511-518 ◽  
Author(s):  
Yohei Watanabe ◽  
Fumiko Nagai ◽  
Masami Morotomi
Keyword(s):  
Bacterial Species ◽  
Short Chain Fatty Acids ◽  
Pcr Analysis ◽  
Rrna Gene ◽  
Gi Tract ◽  
Bacterial Strains ◽  
High Sequence Identity ◽  
Healthy Human ◽  
Content Type

ABSTRACTIsolation, cultivation, and characterization of the intestinal microorganisms are important for understanding the comprehensive physiology of the human gastrointestinal (GI) tract microbiota. Here, we isolated two novel bacterial strains, YIT 12067Tand YIT 12068, from the feces of healthy human adults. Phylogenetic analysis indicated that they belonged to the same species and were most closely related toPhascolarctobacterium faeciumACM 3679T, with 91.4% to 91.5% 16S rRNA gene sequence similarities, respectively. Substrate availability tests revealed that the isolates used only succinate; they did not ferment any other short-chain fatty acids or carbohydrates tested. When these strains were cocultured with the xylan-utilizing and succinate-producing bacteriumParaprevotella xylaniphilaYIT 11841T, in medium supplemented with xylan but not succinate, their cell numbers became 2 to 3 orders of magnitude higher than those of the monoculture; succinate became undetectable, and propionate was formed. Database analysis revealed that over 200 uncultured bacterial clones from the feces of humans and other mammals showed high sequence identity (>98.7%) to YIT 12067T. Real-time PCR analysis also revealed that YIT 12067T-like bacteria were present in 21% of human fecal samples, at an average level of 3.34 × 108cells/g feces. These results indicate that YIT 12067T-like bacteria are distributed broadly in the GI tract as subdominant members that may adapt to the intestinal environment by specializing to utilize the succinate generated by other bacterial species. The phylogenetic and physiological properties of YIT 12067Tand YIT 12068 suggest that these strains represent a novel species, which we have designatedPhascolarctobacterium succinatutenssp. nov.

scholarly journals Population Trends and Urbanisation in Mountain Ranges of the World

Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 255
Author(s):  
Daniele Ehrlich ◽  
Michele Melchiorri ◽  
Claudia Capitani
Keyword(s):  
Rural Areas ◽  
Population Change ◽  
Population Trends ◽  
Time Range ◽  
Mountain Range ◽  
Mountain Areas ◽  
Population Total ◽  
Mountain Ranges ◽  
The World ◽  
Mountain Population

This study assesses the global mountain population, population change over the 1975–2015 time-range, and urbanisation for 2015. The work uses the World Conservation Monitoring Centre (WCMC) definition of mountain areas combined with that of mountain range outlines generated by the Global Mountain Biodiversity Assessment (GMBA). We estimated population change from the Global Human Settlement Layer Population spatial grids, a set of population density layers used to measure human presence and urbanisation on planet Earth. We show that the global mountain population has increased from over 550 million in 1975 to over 1050 million in 2015. The population is concentrated in mountain ranges at low latitudes. The most populated mountain ranges are also the most urbanised and those that grow most. Urbanisation in mountains (66%) is lower than that of lowlands (78%). However, 34% of the population in mountains live in cities, 31% in towns and semi-dense areas, and 35% in rural areas. The urbanisation rate varies considerably across ranges. The assessments of population total, population trends, and urbanisation may be used to address the issue “not to leave mountain people behind” in the sustainable development process and to understand trajectories of change.

scholarly journals THE IDENTIFICATION, PRODUCTION AND CHARACTERIZATION OF NATTOKINASE, BACTERIOCIN FROM BACTERIAL SPECIES

2019 ◽  
Vol 2 (4) ◽  
pp. 91
Author(s):  
Lal Krishna
Keyword(s):  
Enzyme Activity ◽  
Bacillus Subtilis ◽  
Pathogenic Bacteria ◽  
Blood Clot ◽  
Bacterial Species ◽  
Antagonistic Activity ◽  
Bacterial Strains ◽  
Wide Range

The study was aimed at identification, production and characterization of nattokinase, bacteriocin from bacterial species. Nattokinase and bacteriocins finds a wide range of applications in Pharmaceutical industry, health care and medicine. Nattokinase is a highly active fibrinolytic enzyme secreted by Bacillus subtilis and bacteriocins are proteinaceous toxins produced by Lactobacillus to inhibit the growth of closely related bacterial strains. Bacillus subtilis and Lactobacillus isolates shown positive results to microscopic, biochemical analysis.  The nattokinase and bacteriocins were produced by optimizing the media. The enzymes were purified by ammonium sulfate precipitation and HPLC. The enzyme activity for nattokinase was found at 7 mg/ml, pH 8.0 and temperature 48 ºC and the enzyme activity for bacteriocin was found at 3.9 mg/ml, pH 6.5 and temperature 30 °C. Bacteriocins from Lactobacillus showed good antagonistic activity against pathogenic bacteria. Nattokinase from Bacillus subtilis played a significant role in thrombolytic and anti-coagulation at in vitro. The results indicated that the pure enzyme has a potential in dissolving blood clot.

scholarly journals Characterization of Two Unique Cold-Active Lipases Derived from a Novel Deep-Sea Cold Seep Bacterium

2021 ◽  
Vol 9 (4) ◽  
pp. 802
Author(s):  
Chenchen Guo ◽  
Rikuan Zheng ◽  
Ruining Cai ◽  
Chaomin Sun ◽  
Shimei Wu
Keyword(s):  
Deep Sea ◽  
Bacterial Species ◽  
Deep Ocean ◽  
Cold Seep ◽  
Bacterial Strains ◽  
E Coli ◽  
Cold Active ◽  
Genes Encoding ◽  
Potential Inhibitors

The deep ocean microbiota has unexplored potential to provide enzymes with unique characteristics. In order to obtain cold-active lipases, bacterial strains isolated from the sediment of the deep-sea cold seep were screened, and a novel strain gcc21 exhibited a high lipase catalytic activity, even at the low temperature of 4 °C. The strain gcc21 was identified and proposed to represent a new species of Pseudomonas according to its physiological, biochemical, and genomic characteristics; it was named Pseudomonas marinensis. Two novel encoding genes for cold-active lipases (Lipase 1 and Lipase 2) were identified in the genome of strain gcc21. Genes encoding Lipase 1 and Lipase 2 were respectively cloned and overexpressed in E. coli cells, and corresponding lipases were further purified and characterized. Both Lipase 1 and Lipase 2 showed an optimal catalytic temperature at 4 °C, which is much lower than those of most reported cold-active lipases, but the activity and stability of Lipase 2 were much higher than those of Lipase 1 under different tested pHs and temperatures. In addition, Lipase 2 was more stable than Lipase 1 when treated with different metal ions, detergents, potential inhibitors, and organic solvents. In a combination of mutation and activity assays, catalytic triads of Ser, Asp, and His in Lipase 1 and Lipase 2 were demonstrated to be essential for maintaining enzyme activity. Phylogenetic analysis showed that both Lipase 1 and Lipase 2 belonged to lipase family III. Overall, our results indicate that deep-sea cold seep is a rich source for novel bacterial species that produce potentially unique cold-active enzymes.

6. Tectonics of continents

2015 ◽  
pp. 89-109
Author(s):  
Peter Molnar
Keyword(s):  
Continental Crust ◽  
Oceanic Crust ◽  
Oceanic Lithosphere ◽  
Mountain Range ◽  
Continental Lithosphere ◽  
Mountain Ranges ◽  
Horizontal Dimension ◽  
The World ◽  
The Alps ◽  
Thin Crust

‘Tectonics of continents’ shows that the much greater thickness of continental than oceanic crust makes continental and oceanic lithosphere behave differently. First, because crust is less dense and therefore buoyant, compared with the mantle, thick continental crust resists subduction into the asthenosphere. Slices of the upper part of the crust detach from underlying parts and become stacked atop one another to form a mountain range, like the Alps or Himalaya. Second, continental lithosphere is weaker than oceanic lithosphere and when put under stress it deforms. When the horizontal dimension of a region of continental crust is shortened, the crust thickens. Because of isostasy, thick buoyant crust stands higher than thin crust, creating mountain ranges. Various mountain ranges around the world are used to illustrate these principles.

Cultivation and characterization of symbiotic bacteria from the gut of Reticulitermes chinensis

2016 ◽  
Vol 1 (1) ◽  
pp. 3 ◽  
Author(s):  
Hao Fang ◽  
Wen Chen ◽  
Baojun Wang ◽  
Xiaojuan Li ◽  
Shuang-Jiang Liu ◽  
...  
Keyword(s):  
Cellulose Degradation ◽  
Sequence Similarity ◽  
Bacterial Species ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Symbiotic Bacteria ◽  
Nitrogen Recycling ◽  
Bacterial Strains ◽  
High Sequence Similarity

The complex symbiotic relationship between wood-feeding termites and microorganisms inhabiting their intestinal tracts is a fascinating phenomenon in nature. To understand the physiological functions of symbiotic micro-organisms, bacteria were isolated from the gut homogenate of Reticulitermes chinensis with different media and culture conditions. Under aerobic conditions, 105 bacterial strains were isolated with 1/5 LB medium, 1/3 TSB medium and a modified basal mineral medium, MM-4. Most dominant isolates were bacteria in the genera Bacillus (27.6%) and Lactococcus (21.9%). Under anaerobic conditions, 60 bacterial strains were isolated with 1/5 LB medium, 1/3 TSB medium and a modified Peptone-Yeast medium. The predominant isolates were bacteria in the genus Enterobacter (41.7%) and Citrobacter (33.3%). Many of these bacterial isolates shared high sequence similarity (>98%) in 16S rRNA genes to bacterial clones obtained from the same termite and the other wood-feeding termites or cockroaches. Several bacterial species such as Deinococcus and Gryllotalpicola were isolated from termite gut for the first time. Characterization of these isolates showed that (i) most of Enterobacteriaceae and Lactococcus strains were able to hydrolyze uric acid; and (ii) many of the Bacillus and Streptomyces strains presented endo-β-1,4-glucanase activity. The preliminary results of this work gave us hints of possible functions of symbiotic bacteria in nitrogen recycling and cellulose degradation in the gut of wood-feeding termites

PERSPECTIVE DEVELOPMENT OF WORLD PRODUCTION OF FEEDS FOR AQUACULTURE: ALTERNATIVE SOURCES OF RAW MATERIALS

2017 ◽  
pp. 67-78
Author(s):  
Lina Yurievna Lagutkina
Keyword(s):  
Raw Materials ◽  
Limiting Factors ◽  
Current Status ◽  
Feed Production ◽  
The World ◽  
Market Trends ◽  
Alternative Sources ◽  
World Industry ◽  
First Time ◽  
A Current

The author of the article discloses the prospects of development of the world feed production for aquaculture based on the analysis of key innovative technological and market trends. The author specifies that shortage, high cost, low ecological compatibility of traditional raw materials - fish flour - are among major limiting factors in the development of production of feeds for aquaculture. This fact, in turn, limits sustainable development of aquaculture both in Russia, and in the world in general. The article presents the overview of a current status of the world industry of feed production in aquaculture, where the regional situation is studied, as well. For the first time, there is given the outlook of innovative technologies in feed production based on the alternative sources of protein (on the example of projects of leading aquabiotechnological companies) which will determine industry’s objectives for the mid-term perspective.

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