scholarly journals Cultivable Bacterial Communities in Brines from Perennially Ice-Covered and Pristine Antarctic Lakes: Ecological and Biotechnological Implications

2020 ◽  
Vol 8 (6) ◽  
pp. 819 ◽  
Author(s):  
Carmen Rizzo ◽  
Antonella Conte ◽  
Maurizio Azzaro ◽  
Maria Papale ◽  
Alessandro C. Rappazzo ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Extracellular Polymeric Substances ◽  
Rrna Gene ◽  
Bacterial Isolates ◽  
Antarctic Lakes ◽  
Bacterial Response ◽  
Victoria Land ◽  
Boulder Clay ◽  
Aliphatic And Aromatic Hydrocarbons ◽  
Sequence Similarities

The diversity and biotechnological potentialities of bacterial isolates from brines of three Antarctic lakes of the Northern Victoria Land (namely Boulder Clay and Tarn Flat areas) were first explored. Cultivable bacterial communities were analysed mainly in terms of bacterial response to contaminants (i.e., antibiotics and heavy metals) and oxidation of contaminants (i.e., aliphatic and aromatic hydrocarbons and polychlorobiphenyls). Moreover, the biosynthesis of biomolecules (antibiotics, extracellular polymeric substances and enzymes) with applications for human health and environmental protection was assayed. A total of 74 and 141 isolates were retrieved from Boulder Clay and Tarn Flat brines, respectively. Based on 16S rRNA gene sequence similarities, bacterial isolates represented three phyla, namely Proteobacteria (i.e., Gamma- and Alphaproteobacteria), Bacteroidetes and Actinobacteria, with differences encountered among brines. At genus level, Rhodobacter, Pseudomonas, Psychrobacter and Leifsonia members were dominant. Results obtained from this study on the physiological and enzymatic features of cold-adapted isolates from Antarctic lake brines provide interesting prospects for possible applications in the biotechnological field through future targeted surveys. Finally, findings on contaminant occurrence and bacterial response suggest that bacteria might be used as bioindicators for tracking human footprints in these remote polar areas.

DIVERSITY OF CULTURABLE BACTERIAL MICROBIOTA OF THE Eisenia foetida DIGESTIVE TRACT

2018 ◽  
Vol 41 (3) ◽  
pp. 255-264 ◽  
Author(s):  
J. Abraham Pérez-Pérez ◽  
David Espinosa-Victoria ◽  
Hilda V. Silva-Rojas ◽  
Lucía López-Reyes
Keyword(s):  
Bacterial Diversity ◽  
Digestive Tract ◽  
Bacterial Species ◽  
Brain Heart Infusion ◽  
Rrna Gene ◽  
Eisenia Foetida ◽  
Bacterial Isolates ◽  
Bacterial Microbiota ◽  
Decomposition Of Organic Matter ◽  
Earthworm Gut

Bacteria are an unavoidable component of the natural earthworm diet; thus, bacterial diversity in the earthworm gut is directly linked to decomposition of organic matter and development of the surrounding plants. The aim of this research was to isolate and to identify biochemically and molecularly the culturable bacterial microbiota of the digestive tract of Eisenia foetida. Earthworms were sourced from Instituto de Reconversión Productiva y Bioenergética (IRBIO) and Colegio de Postgraduados (COLPOS), México. Bacterial isolation was carried out on plates of Brain Heart Infusion (BHI) culture medium. Fifty six and 44 bacterial isolates were obtained from IRBIO and COLPOS, respectively. The population was composed of 44 Gram-negative and 56 Gram-positive isolates. Over 50 % of the bacterial isolates were rod-shaped cells. The 16S rRNA gene was sequenced and nine genera were identified in worms from IRBIO (Bacillus, Paenibacillus, Solibacillus, Staphylococcus, Arthrobacter, Pantoea, Stenotrophomonas, Acinetobacter and Aeromonas) and six in worms from COLPOS (Bacillus, Paenibacillus, Stenotrophomonas, Staphylococcus, Acinetobacter and Aeromonas). Bacillus was the predominant genus, with eight and six species in the oligochaetes from IRBIO and COLPOS, respectively. The most represented bacteria in the worms from both sites were Bacillus sp. and B. subtilis. The predominance of Bacillus was probably due to spore formation, a reproductive strategy that ensures survival and dispersion in the soil and oligochaetes digestive tract. The gut of E. foetida not only harbored bacterial species of agronomic importance but also species potentially pathogenic for humans (Staphylococcus warneri, Pantoea agglomerans and Stentrophomonas sp.). The larger bacterial diversity in worms from IRBIO could be due to their feeding on cattle manure, which is a rich source of bacteria.

scholarly journals The capacity of wastewater treatment plants drives bacterial community structure and its assembly

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Young Kyung Kim ◽  
Keunje Yoo ◽  
Min Sung Kim ◽  
Il Han ◽  
Minjoo Lee ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Community Structure ◽  
Bacterial Community ◽  
Activated Sludge ◽  
Community Assembly ◽  
Bacterial Communities ◽  
Wastewater Treatment Plants ◽  
High Capacity ◽  
Operating Conditions ◽  
Rrna Gene

Abstract Bacterial communities in wastewater treatment plants (WWTPs) affect plant functionality through their role in the removal of pollutants from wastewater. Bacterial communities vary extensively based on plant operating conditions and influent characteristics. The capacity of WWTPs can also affect the bacterial community via variations in the organic or nutrient composition of the influent. Despite the importance considering capacity, the characteristics that control bacterial community assembly are largely unknown. In this study, we discovered that bacterial communities in WWTPs in Korea and Vietnam, which differ remarkably in capacity, exhibit unique structures and interactions that are governed mainly by the capacity of WWTPs. Bacterial communities were analysed using 16S rRNA gene sequencing and exhibited clear differences between the two regions, with these differences being most pronounced in activated sludge. We found that capacity contributed the most to bacterial interactions and community structure, whereas other factors had less impact. Co-occurrence network analysis showed that microorganisms from high-capacity WWTPs are more interrelated than those from low-capacity WWTPs, which corresponds to the tighter clustering of bacterial communities in Korea. These results will contribute to the understanding of bacterial community assembly in activated sludge processing.

scholarly journals A Grain-Based SARA Challenge Affects the Composition of Epimural and Mucosa-Associated Bacterial Communities throughout the Digestive Tract of Dairy Cows

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1658
Author(s):  
Jan C. Plaizier ◽  
Anne-Mette Danscher ◽  
Paula A. Azevedo ◽  
Hooman Derakhshani ◽  
Pia H. Andersen ◽  
...  
Keyword(s):  
Digestive Tract ◽  
Relative Abundance ◽  
Bacterial Communities ◽  
Dry Matter ◽  
Control Diet ◽  
Rrna Gene ◽  
Ruminal Acidosis ◽  
Clustering Patterns ◽  
The 16S Rrna Gene ◽  
Distal Jejunum

The effects of a subacute ruminal acidosis (SARA) challenge on the composition of epimural and mucosa-associated bacterial communities throughout the digestive tract were determined in eight non-lactating Holstein cows. Treatments included feeding a control diet containing 19.6% dry matter (DM) starch and a SARA-challenge diet containing 33.3% DM starch for two days after a 4-day grain step-up. Subsequently, epithelial samples from the rumen and mucosa samples from the duodenum, proximal, middle and distal jejunum, ileum, cecum and colon were collected. Extracted DNA from these samples were analyzed using MiSeq Illumina sequencing of the V4 region of the 16S rRNA gene. Distinct clustering patterns for each diet existed for all sites. The SARA challenge decreased microbial diversity at all sites, with the exception of the middle jejunum. The SARA challenge also affected the relative abundances of several major phyla and genera at all sites but the magnitude of these effects differed among sites. In the rumen and colon, the largest effects were an increase in the relative abundance of Firmicutes and a reduction of Bacteroidetes. In the small intestine, the largest effect was an increase in the relative abundance of Actinobacteria. The grain-based SARA challenge conducted in this study did not only affect the composition and cause dysbiosis of epimural microbiota in the rumen, it also affected the mucosa-associated microbiota in the intestines. To assess the extent of this dysbiosis, its effects on the functionality of these microbiota must be determined in future.

scholarly journals Diversity and Biocontrol Potential of Cultivable Endophytic Bacteria Associated with Halophytes from the West Aral Sea Basin

2021 ◽  
Vol 9 (7) ◽  
pp. 1448
Author(s):  
Lei Gao ◽  
Jinbiao Ma ◽  
Yonghong Liu ◽  
Yin Huang ◽  
Osama Abdalla Abdelshafy Mohamad ◽  
...  
Keyword(s):  
Endophytic Bacteria ◽  
Diversity Index ◽  
Pathogenic Fungi ◽  
Significant Inhibition ◽  
Isolation Effect ◽  
Aral Sea ◽  
Rrna Gene ◽  
Bacterial Isolates ◽  
Aral Sea Basin ◽  
Soil Borne Pathogens

Endophytes associated with halophytes may contribute to the host’s adaptation to adverse environmental conditions through improving their stress tolerance and protecting them from various soil-borne pathogens. In this study, the diversity and antifungal activity of endophytic bacteria associated with halophytic samples growing on the shore of the western Aral Sea in Uzbekistan were investigated. The endophytic bacteria were isolated from the nine halophytic samples by using the culture-dependent method and identified according to their 16S rRNA gene sequences. The screening of endophytic bacterial isolates with the ability to inhibit pathogenic fungi was completed by the plate confrontation method. A total of 289 endophytic bacterial isolates were isolated from the nine halophytes, and they belong to Firmicutes, Actinobacteria, and Proteobacteria. The predominant genera of the isolated endophytic bacteria were Bacillus, Staphylococcus, and Streptomyces, accounting for 38.5%, 24.7%, and 12.5% of the total number of isolates, respectively. The comparative analysis indicated that the isolation effect was better for the sample S8, with the highest diversity and richness indices. The diversity index of the sample S7 was the lowest, while the richness index of samples S5 and S6 was the lowest. By comparing the isolation effect of 12 different media, it was found that the M7 medium had the best performance for isolating endophytic bacteria associated with halophytes in the western Aral Sea Basin. In addition, the results showed that only a few isolates have the ability to produce ex-enzymes, and eight and four endophytic bacterial isolates exhibited significant inhibition to the growth of Valsa mali and Verticillium dahlia, respectively. The results of this study indicated that halophytes are an important source for the selection of microbes that may protect plant from soil-borne pathogens.

scholarly journals New Chitosan-Degrading Strains That Produce Chitosanases Similar to ChoA of Mitsuaria chitosanitabida

2005 ◽  
Vol 71 (9) ◽  
pp. 5138-5144 ◽  
Author(s):  
ChoongSoo Yun ◽  
Daiki Amakata ◽  
Yasuhiro Matsuo ◽  
Hideyuki Matsuda ◽  
Makoto Kawamukai
Keyword(s):  
Southern Hybridization ◽  
Glycosyl Hydrolase ◽  
Pcr Amplification ◽  
Rrna Gene ◽  
16S Rrna Gene Sequences ◽  
Glycosyl Hydrolase Family ◽  
Broad Variety ◽  
Hydrolase Family ◽  
The 16S Rrna Gene ◽  
Sequence Similarities

ABSTRACT The betaproteobacterium Mitsuaria chitosanitabida (formerly Matsuebacter chitosanotabidus) 3001 produces a chitosanase (ChoA) that is classified in glycosyl hydrolase family 80. While many chitosanase genes have been isolated from various bacteria to date, they show limited homology to the M. chitosanitabida 3001 chitosanase gene (choA). To investigate the phylogenetic distribution of chitosanases analogous to ChoA in nature, we identified 67 chitosan-degrading strains by screening and investigated their physiological and biological characteristics. We then searched for similarities to ChoA by Western blotting and Southern hybridization and selected 11 strains whose chitosanases showed the most similarity to ChoA. PCR amplification and sequencing of the chitosanase genes from these strains revealed high deduced amino acid sequence similarities to ChoA ranging from 77% to 99%. Analysis of the 16S rRNA gene sequences of the 11 selected strains indicated that they are widely distributed in the β and γ subclasses of Proteobacteria and the Flavobacterium group. These observations suggest that the ChoA-like chitosanases that belong to family 80 occur widely in a broad variety of bacteria.

Molecular characterization of the bacterial communities present in sheep's milk and cheese produced in South Brazilian Region via 16S rRNA gene metabarcoding sequencing

LWT ◽  
2021 ◽  
Vol 147 ◽  
pp. 111579
Author(s):  
Creciana M. Endres ◽  
Ícaro Maia S. Castro ◽  
Laura D. Trevisol ◽  
Juliana M. Severo ◽  
Michele B. Mann ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Molecular Characterization ◽  
Bacterial Communities ◽  
Rrna Gene

scholarly journals Paenibacillus xinjiangensis sp. nov., isolated from Xinjiang province in China

2006 ◽  
Vol 56 (11) ◽  
pp. 2579-2582 ◽  
Author(s):  
Jee-Min Lim ◽  
Che Ok Jeon ◽  
Dong-Jin Park ◽  
Li-Hua Xu ◽  
Cheng-Lin Jiang ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
Diaminopimelic Acid ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
16S Rrna Gene Sequences ◽  
Sequence Similarities

Strain B538T is a Gram-positive, motile, rod-shaped bacterium, which was isolated from Xinjiang province in China. This organism grew optimally at 30–35 °C and pH 8.0–8.5. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain B538T belonged to the genus Paenibacillus and chemotaxonomic data (DNA G+C content, 47.0 mol%; major isoprenoid quinone, MK-7; cell wall type, A1γ meso-diaminopimelic acid; major fatty acids, anteiso-C15 : 0 and C16 : 0) supported affiliation of the isolate with the genus Paenibacillus. Comparative 16S rRNA gene sequence analyses showed that the isolate was most closely related to Paenibacillus glycanilyticus DS-1T, with 16S rRNA gene sequence similarity of 98.1 %; sequence similarities to other members of the genus Paenibacillus used in the phylogenetic tree were less than 96.5 %. The DNA–DNA relatedness between strain B538T and P. glycanilyticus DS-1T was about 8.0 %. On the basis of physiological and molecular properties, strain B538T (=KCTC 3952T=DSM 16970T) is proposed as the type strain of a novel species within the genus Paenibacillus, for which the name Paenibacillus xinjiangensis sp. nov. is proposed.

scholarly journals Natribacillus halophilus gen. nov., sp. nov., a moderately halophilic and alkalitolerant bacterium isolated from soil

2012 ◽  
Vol 62 (2) ◽  
pp. 289-294 ◽  
Author(s):  
Akinobu Echigo ◽  
Hiroaki Minegishi ◽  
Yasuhiro Shimane ◽  
Masahiro Kamekura ◽  
Ron Usami
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Sequence Similarity ◽  
Diaminopimelic Acid ◽  
Garden Soil ◽  
Rrna Gene ◽  
Moderately Halophilic ◽  
Acid Type ◽  
Optimum Ph ◽  
Sequence Similarities

A moderately halophilic and alkalitolerant bacterium, designated strain HN30T, was isolated from garden soil in Japan. Cells of strain HN30T were motile, endospore-forming, aerobic, rod-shaped and Gram-positive, and contained A1γ meso-diaminopimelic acid-type murein. Growth occurred in 7–23 % (w/v) NaCl (optimum, 10–15 %, w/v), at pH 6.5–10.0 (optimum, pH 8.0–8.5) and at 20–40 °C (optimum, 30 °C). The isoprenoid quinone was menaquinone-7. The polar lipids were phosphatidylglycerol and diphosphatidylglycerol. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0, iso-C16 : 0 and C16 : 0. The DNA G+C content of strain HN30T was 47 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain HN30T was most closely related to Geomicrobium halophilum BH1T (93 % sequence similarity). 16S rRNA gene sequence similarities with other recognized species were less than 89 %. Phylogenetic and phenotypic characteristics indicated that strain HN30T represents a novel species in a new genus, for which the name Natribacillus halophilus gen. nov., sp. nov. is proposed; the type strain is HN30T ( = JCM 15649T = DSM 21771T).

scholarly journals Cyclobacterium qasimii sp. nov., a psychrotolerant bacterium isolated from Arctic marine sediment

2012 ◽  
Vol 62 (Pt_9) ◽  
pp. 2133-2139 ◽  
Author(s):  
S. Shivaji ◽  
P. Vishnu Vardhan Reddy ◽  
S. S. S. Nageshwara Rao ◽  
Zareena Begum ◽  
Poorna Manasa ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Marine Sediment ◽  
Dna Hybridization ◽  
Type Species ◽  
Unsaturated Fatty Acids ◽  
Rrna Gene ◽  
Respiratory Quinone ◽  
Content Type ◽  
Link Type ◽  
Sequence Similarities

A novel Gram-stain-negative, horseshoe-shaped, non-motile bacterium, designated strain M12-11BT, was isolated from a marine sediment sample collected at a depth of 200 m from Kongsfjorden, Svalbard. The colony colour was orangish red due to the presence of carotenoids. Fatty acids were dominated by branched and unsaturated fatty acids (90.8 %), with a high abundance of iso-C15 : 0 (14.9 %), anteiso-C15 : 0 (11.4 %), iso-C15 : 1 G (13.1 %), C15 : 1ω6c (5.4 %), C17 : 1ω6c (6.7 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 9.3 %) and summed feature 9 (10-methyl C16 : 0 and/or iso-C17 : 1ω9c; 5.9 %). Strain M12-11BT contained MK-7 as the major respiratory quinone. The polar lipids consisted of phosphatidylcholine, phosphatidylethanolamine, one unidentified aminolipid and three unidentified lipids. Based on 16S rRNA gene sequence similarities, the type strains of Cyclobacterium amurskyense , Cyclobacterium marinum and Cyclobacterium lianum were most closely related to M12-11BT with sequence similarities of 98.2, 96.8 and 93.3 %, respectively. Other members of the family Cyclobacteriaceae had sequence similarities of <92.0 %. However, DNA–DNA hybridization with Cyclobacterium amurskyense KCTC 12363T and Cyclobacterium marinum DSM 745T showed relatedness values of only 24.5 and 32.5 % with respect to strain M12-11BT. Based on the results of DNA–DNA hybridization experiments and phenotypic and chemotaxonomic data, it appears that strain M12-11BT represents a novel species of the genus Cyclobacterium , for which the name Cyclobacterium qasimii sp. nov. is proposed; the type strain is M12-11BT ( = KCTC 23011T = NBRC 106168T) and it has a DNA G+C content of 40.5 mol%.

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