scholarly journals Novel Psychrophiles and Exopolymers from Permafrost Thaw Lake Sediments

2020 ◽  
Vol 8 (9) ◽  
pp. 1282
Author(s):  
Ilaria Finore ◽  
Adrien Vigneron ◽  
Warwick F. Vincent ◽  
Luigi Leone ◽  
Paola Di Donato ◽  
...  
Keyword(s):  
Extracellular Enzymes ◽  
Extreme Environments ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Ice Melt ◽  
Permafrost Thaw ◽  
Phenotypic And Genetic Characterization ◽  
Pseudomonas Extremaustralis ◽  
Commercial Polymers ◽  
Thaw Lakes

Thermokarst lakes are one of the most abundant types of microbial ecosystems in the circumpolar North. These shallow basins are formed by the thawing and collapse of ice-rich permafrost, with subsequent filling by snow and ice melt. Until now, permafrost thaw lakes have received little attention for isolation of microorganisms by culture-based analysis. The discovery of novel psychrophiles and their biomolecules makes these extreme environments suitable sources for the isolation of new strains, including for potential biotechnological applications. In this study, samples of bottom sediments were collected from three permafrost thaw lakes in subarctic Québec, Canada. Their diverse microbial communities were characterized by 16S rRNA gene amplicon analysis, and subsamples were cultured for the isolation of bacterial strains. Phenotypic and genetic characterization of the isolates revealed affinities to the genera Pseudomonas, Paenibacillus, Acinetobacter,Staphylococcus and Sphingomonas. The isolates were then evaluated for their production of extracellular enzymes and exopolymers. Enzymes of potential biotechnological interest included α and β-glucosidase, α and β-maltosidase, β-xylosidase and cellobiohydrolase. One isolate, Pseudomonas extremaustralis strain 2ASCA, also showed the capability to produce, in the loosely bound cell fraction, a levan-type polysaccharide with a yield of 613 mg/L of culture, suggesting its suitability as a candidate for eco-sustainable alternatives to commercial polymers.

scholarly journals Pseudomonas kitaguniensis sp. nov., a pathogen causing bacterial rot of Welsh onion in Japan

2020 ◽  
Vol 70 (5) ◽  
pp. 3018-3026 ◽  
Author(s):  
Hiroyuki Sawada ◽  
Takashi Fujikawa ◽  
Yoshie Nishiwaki ◽  
Harukuni Horita
Keyword(s):  
Type Species ◽  
Phylogenomic Analysis ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Gene Sequences ◽  
Welsh Onion ◽  
Content Type ◽  
Link Type ◽  
Bacterial Rot ◽  
Pseudomonas Extremaustralis

Five Gram-reaction-negative, aerobic, motile with one to three polar flagella, rod-shaped bacterial strains, MAFF 212408T, MAFF 212409, MAFF 212410, MAFF 301498 and MAFF 730085, were isolated from diseased Welsh onion (Allium fistulosum L.) in Japan. Analysis of their 16S rRNA gene sequences showed that they belong to the genus Pseudomonas with the highest similarity to Pseudomonas extremaustralis 14-3T (99.86 %), Pseudomonas antarctica CMS 35T (99.79 %) and Pseudomonas poae DSM 14936T (99.72%). The genomic DNA G+C content was 59.5 mol% and the major fatty acids (>5 %) were summed feature 3, C16 : 0, summed feature 8 and C12 : 0 2-OH. Multilocus sequence analysis using the rpoD, gyrB and rpoB gene sequences and phylogenomic analysis based on the 90 core genes demonstrated that the strains are members of the P. fluorescens subgroup, but are distant from all closely related species. Average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) analysis confirmed low genomic relatedness to their closest relatives [below the recommended thresholds of 95 % (ANI) and 70 % (dDDH) for prokaryotic species delineation]. The strains were characterized by using API 20NE and Biolog GEN III tests, and inoculation tests in Welsh onion, showing that they are phenotypically differentiated from their closest relatives. Based on the genetic and phenotypic evidence, the strains should be classified as representing a novel species, for which the name Pseudomonas kitaguniensis sp. nov. is proposed. The type strain is MAFF 212408T (=ICMP 23530T).

scholarly journals Campylobacter insulaenigrae bacteremia with meningitis: a case report

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Moe Kyotani ◽  
Tsuneaki Kenzaka ◽  
Hozuka Akita ◽  
Soichi Arakawa
Keyword(s):  
Blood Culture ◽  
Marine Mammals ◽  
Chronic Subdural Hematoma ◽  
16S Rrna Gene Sequencing ◽  
Enhancement Effect ◽  
Rrna Gene ◽  
Clinical Report ◽  
Bacterial Strains ◽  
Fisher Syndrome ◽  
First Case

Abstract Background The bacterium Campylobacter insulaenigrae was first isolated from marine mammals of Scotland in 2004. Only one case of C. insulaenigrae infection in humans has been previously reported. Case presentation An 89-year-old Japanese man without dementia was admitted to our hospital, because he presented with a fever of 38 °C and weakness in right leg since 5 days. He had organized chronic subdural hematoma (CSH), and no history of pre-infection. At the time of admission, he had paralysis of the extraocular muscle, ataxia, and low manual muscle test score of the right side. He was suspected to have Miller Fisher syndrome; however, these symptoms improved without any treatment. On day 22 in the hospital, the patient presented a fever of 38.8 °C, left cranial nerve disorder, and hemiplegia. On day 25, the patient presented with signs of meningeal irritation; cerebrospinal fluid examination indicated an increase in the number of apocytes and a low glucose level. A contrast magnetic resonance imaging (MRI) scan of the patient’s head indicated a contrast enhancement effect in his right meninges. The blood culture showed presence of spirillums; 16S rRNA gene sequencing confirmed that the spirillums in the blood culture were Campylobacter insulaenigrae (C. insulaenigrae). We started treatment with meropenem for bacteremia and meningitis. When the symptoms improved, meropenem was replaced with ampicillin, based on the result of the drug sensitivity test. The treatment continued for 4 weeks. Conclusions We report the first case of meningitis caused by C. insulaenigrae bacteremia in humans, and the second clinical report of C. insulaenigrae infection in humans. The bacterial strains isolated from humans and marine mammals had different genotypes. This suggests that different genotypes could be responsible for differences in the hosts. Further case studies are needed to establish the reasons behind the difference in the manifestations of C. insulaenigrae infections reported so far.

scholarly journals Microbiome of Odontogenic Abscesses

2021 ◽  
Vol 9 (6) ◽  
pp. 1307
Author(s):  
Sebastian Böttger ◽  
Silke Zechel-Gran ◽  
Daniel Schmermund ◽  
Philipp Streckbein ◽  
Jan-Falco Wilbrand ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Oral Microbiome ◽  
Minor Role ◽  
Rrna Gene ◽  
Sequencing Analysis ◽  
Bacterial Strains ◽  
16S Rrna Gene Analysis ◽  
Odontogenic Infections ◽  
Odontogenic Abscess

Severe odontogenic abscesses are regularly caused by bacteria of the physiological oral microbiome. However, the culture of these bacteria is often prone to errors and sometimes does not result in any bacterial growth. Furthermore, various authors found completely different bacterial spectra in odontogenic abscesses. Experimental 16S rRNA gene next-generation sequencing analysis was used to identify the microbiome of the saliva and the pus in patients with a severe odontogenic infection. The microbiome of the saliva and the pus was determined for 50 patients with a severe odontogenic abscess. Perimandibular and submandibular abscesses were the most commonly observed diseases at 15 (30%) patients each. Polymicrobial infections were observed in 48 (96%) cases, while the picture of a mono-infection only occurred twice (4%). On average, 31.44 (±12.09) bacterial genera were detected in the pus and 41.32 (±9.00) in the saliva. In most cases, a predominantly anaerobic bacterial spectrum was found in the pus, while saliva showed a similar oral microbiome to healthy individuals. In the majority of cases, odontogenic infections are polymicrobial. Our results indicate that these are mainly caused by anaerobic bacterial strains and that aerobic and facultative anaerobe bacteria seem to play a more minor role than previously described by other authors. The 16S rRNA gene analysis detects significantly more bacteria than conventional methods and molecular methods should therefore become a part of routine diagnostics in medical microbiology.

scholarly journals Identification and Genomic Characterization of Pathogenic Bacillus altitudinis from Common Pear Trees in Morocco

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1344
Author(s):  
Naima Lemjiber ◽  
Khalid Naamani ◽  
Annabelle Merieau ◽  
Abdelhi Dihazi ◽  
Nawal Zhar ◽  
...  
Keyword(s):  
16S Rrna Gene Sequencing ◽  
Genomic Islands ◽  
Rrna Gene ◽  
In Planta ◽  
Bacterial Strains ◽  
Bacillus Altitudinis ◽  
Genes Encoding ◽  
Bacillus Spp ◽  
Pear Trees ◽  
Rrna Gene Sequencing

Bacterial burn is one of the major diseases affecting pear trees worldwide, with serious impacts on producers and economy. In Morocco, several pear trees (Pyrus communis) have shown leaf burns since 2015. To characterize the causal agent of this disease, we isolated fourteen bacterial strains from different parts of symptomatic pear trees (leaves, shoots, fruits and flowers) that were tested in planta for their pathogenicity on Louise bonne and Williams cultivars. The results showed necrotic lesions with a significant severity range from 47.63 to 57.77% on leaves of the Louise bonne cultivar inoculated with isolate B10, while the other bacterial isolates did not induce any disease symptom. 16S rRNA gene sequencing did not allow robust taxonomic discrimination of the incriminated isolate. Thus, we conducted whole-genome sequencing (WGS) and phylogenetic analyzes based on gyrA, gyrB and cdaA gene sequences, indicating that this isolate belongs to the Bacillus altitudinis species. This taxonomic classification was further confirmed by the Average Nucleotide Identity (ANI) and the in silico DNA-DNA hybridization (isDDH) analyzes compared to sixty-five Bacillus spp. type strains. The genome was mined for genes encoding carbohydrate-active enzymes (CAZymes) known to play a role in the vegetal tissue degradation. 177 candidates with functions that may support the in planta phytopathogenicity results were identified. To the best of our knowledge, this is the first data reporting B. altitudinis as agent of leaf burn in P. communis in Morocco. Our dataset will improve our knowledge on spread and pathogenicity of B. altitudinis genotypes that appears as emergent phytopathogenic agent, unveiling virulence factors and their genomic location (i.e., within genomic islands or the accessory genome) to induce trees disease.

scholarly journals Umboniibacter marinipuniceus gen. nov., sp. nov., a marine gammaproteobacterium isolated from the mollusc Umbonium costatum from the Sea of Japan

2010 ◽  
Vol 60 (3) ◽  
pp. 603-609 ◽  
Author(s):  
Lyudmila A. Romanenko ◽  
Naoto Tanaka ◽  
Galina M. Frolova
Keyword(s):  
Sea Of Japan ◽  
Sequence Similarity ◽  
Fatty Acid Analysis ◽  
Phenotypic Characterization ◽  
The Sea Of Japan ◽  
Rrna Gene ◽  
Phylogenetic Distance ◽  
The Novel ◽  
Bacterial Strains ◽  
Separate Branch

Two bacterial strains, KMM 3891T and KMM 3892, were isolated from internal tissues of the marine mollusc Umbonium costatum collected from the Sea of Japan. The novel isolates were Gram-negative, aerobic, faint pink–reddish-pigmented, rod-shaped, non-motile, stenohaline and psychrotolerant bacteria that were unable to degrade most tested complex polysaccharides. Polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Fatty acid analysis revealed C17 : 1 ω6c, C17 : 0, C16 : 0 and C16 : 1 ω7c as the dominant components. The major isoprenoid quinone was Q-7. The DNA G+C content of strain KMM 3891T was 51.7 mol%. According to phylogenetic analysis of 16S rRNA gene sequences, strains KMM 3891T and KMM 3892 were positioned within the Gammaproteobacteria as a separate branch, sharing <93 % sequence similarity to their phylogenetic relatives including Saccharophagus degradans, Microbulbifer species, Endozoicomonas elysicola, Simiduia agarivorans and Teredinibacter turnerae. Based on phenotypic characterization and phylogenetic distance, the novel marine isolates KMM 3891T and KMM 3892 represent a new genus and species, for which the name Umboniibacter marinipuniceus gen. nov., sp. nov. is proposed. The type strain of Umboniibacter marinipuniceus is KMM 3891T (=NRIC 0753T =JCM 15738T).

scholarly journals Rhizobium oryzicola sp. nov., potential plant-growth-promoting endophytic bacteria isolated from rice roots

2015 ◽  
Vol 65 (Pt_9) ◽  
pp. 2931-2936 ◽  
Author(s):  
Xiao-Xia Zhang ◽  
Ju-Sheng Gao ◽  
Yan-Hua Cao ◽  
Rizwan Ali Sheirdil ◽  
Xiu-Cheng Wang ◽  
...  
Keyword(s):  
Type Strain ◽  
Housekeeping Genes ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Astragalus Sinicus ◽  
Dna Relatedness ◽  
Rice Roots ◽  
Long Term Experiment ◽  
Plant Growth Promoting

Bacterial strains ZYY136T and ZYY9 were isolated from surface-sterilized rice roots from a long-term experiment of rice–rice–Astragalus sinicus rotation. The 16S rRNA gene sequences of strains ZYY136T and ZYY9 showed the highest similarity, of 97.0  %, to Rhizobium tarimense PL-41T. Sequence analysis of the housekeeping genes recA, thrC and atpD clearly differentiated the isolates from currently described species of the genus Rhizobium. The DNA–DNA relatedness value between ZYY136T and ZYY9 was 82.3  %, and ZYY136T showed 34.0  % DNA–DNA relatedness with the most closely related type strain, R. tarimense PL-41T. The DNA G+C content of strain ZYY136T was 58.1 mol%. The major cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0 and C16 : 0 3-OH. Strains ZYY136T and ZYY9 could be differentiated from the previously defined species of the genus Rhizobium by several phenotypic characteristics. Therefore, we conclude that strains ZYY136T and ZYY9 represent a novel species of the genus Rhizobium, for which the name Rhizobium oryzicola sp. nov. is proposed (type strain ZYY136T = ACCC 05753T = KCTC 32088T).

Chitinophaga oryzae sp. nov., an epiphytic bacterium isolated from rice root surfaces

2021 ◽  
Vol 71 (7) ◽  
Author(s):  
Nantawan Niemhom ◽  
Chanwit Suriyachadkun ◽  
Chokchai Kittiwongwattana
Keyword(s):  
Type Species ◽  
Rrna Gene ◽  
Major Polar Lipid ◽  
Bacterial Strains ◽  
Respiratory Quinone ◽  
Content Type ◽  
Link Type ◽  
Major Respiratory Quinone ◽  
Phylogenomic Analyses ◽  
Close Relatives

Two Gram-stain-negative, non-motile, rod-shaped bacterial strains were isolated from the surfaces of rice roots. They were designated as strains 1303T and 1310. Their colonies were circular, entire, opaque, convex and yellow. They were chitinase- and catalase-positive, reduced nitrate and grew at 16–37 °C (optimum, 30 °C), pH 5.0–10.0 (optimum, pH 7.0) and 0–2.0% NaCl (optimum, 1.0 %). Based on the 16S rRNA gene sequence analysis, they were classified as members of the genus Chitinophaga . Results of phylogenetic and phylogenomic analyses indicated that they formed a cluster with Chitinophaga eiseniae YC6729T, Chitinophaga qingshengii JN246T, Chitinophaga varians 10-7 W-9003T and Chitinophaga fulva G-6-1-13T. When the genomic sequences of strains 1303T and 1310 were compared with their close relatives, the average nucleotide identity and digital DNA–DNA hybridization values were below the cut-off levels. Phosphatidylethanolamine was the major polar lipid. MK-7 was the major respiratory quinone. iso-C15 : 0, C16 : 1  ω5c, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1  ω7c/C16 : 1  ω6c) were the predominant fatty acids. Differential characteristics between both strains and their close relatives were also observed. Based on the distinctions in genotypic, phenotypic and chemotypic features, strains 1303T and 1310 represent members of a novel species of the genus Chitinophaga , for which the name Chitinophaga oryzae sp. nov. is proposed. The type strain is 1303T (=KACC 22075T=TBRC 12926T).

Actinomyces marmotae sp. nov. and Actinomyces procaprae sp. nov. isolated from wild animals and reclassification of Actinomyces liubingyangii and Actinomyces tangfeifanii as Boudabousia liubingyangii comb. nov. and Boudabousia tangfeifanii comb. nov., respectively

2019 ◽  
Vol 71 (3) ◽  
Author(s):  
Caixin Yang ◽  
Yibo Bai ◽  
Kui Dong ◽  
Jing Yang ◽  
Xin-He Lai ◽  
...  
Keyword(s):  
Type Species ◽  
Phylogenetic Analyses ◽  
Brain Heart Infusion ◽  
Tibet Plateau ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Content Type ◽  
Link Type ◽  
Pr China ◽  
Qinghai Tibet Plateau

Four Gram-stain-positive, catalase-negative, non-spore-forming, rod-shaped bacterial strains (zg-325T, zg329, dk561T and dk752) were isolated from the respiratory tract of marmot (Marmota himalayana) and the faeces of Tibetan gazelle (Procapra picticaudata) from the Qinghai-Tibet Plateau of PR China. The results of 16S rRNA gene sequence-based phylogenetic analyses indicated that strains zg-325T and dk561T represent members of the genus Actinomyces , most similar to Actinomyces denticolens DSM 20671T and Actinomyces ruminicola B71T, respectively. The DNA G+C contents of strains zg-325T and dk561T were 71.6 and 69.3 mol%, respectively. The digital DNA–DNA hybridization values of strains zg-325T and dk561T with their most closely related species were below the 70 % threshold for species demarcation. The four strains grew best at 35 °C in air containing 5 % CO2 on brain heart infusion (BHI) agar with 5 % sheep blood. All four strains had C18:1ω9c and C16:0 as the major cellular fatty acids. MK-8 and MK-9 were the major menaquinones in zg-325T while MK-10 was predominant in dk561T. The major polar lipids included diphosphatidylglycerol and phosphatidylinositol. On the basis of several lines of evidence from phenotypic and phylogenetic analyses, zg-325T and dk561T represent novel species of the genus Actinomyces , for which the name Actinomyces marmotae sp. nov. and Actinomyces procaprae sp. nov. are proposed. The type strains are zg-325T (=GDMCC 1.1724T=JCM 34091T) and dk561T (=CGMCC 4.7566T=JCM 33484T). We also propose, on the basis of the phylogenetic results herein, the reclassification of Actinomyces liubingyangii and Actinomyces tangfeifanii as Boudabousia liubingyangii comb. nov. and Boudabousia tangfeifanii comb. nov., respectively.

scholarly journals Diversity of Culturable Actinomycetes from Deepsea Floor of Makassar Strait, Indonesia

2018 ◽  
Vol 3 (2) ◽  
pp. 73
Author(s):  
Ariani Hatmanti ◽  
Puspita Lisdiyanti ◽  
Jaka Widada ◽  
Subagus Wahyuono
Keyword(s):  
16S Rrna ◽  
Gene Sequence ◽  
Sodium Dodecyl ◽  
Extreme Environments ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Track Record ◽  
Centrifugation Method ◽  
Isolation Media ◽  
Active Substances

With regard to collaboration research called Widya Nusantara Exploration (EWIN) in May-June 2013 and November 2014, a study on isolation of actinomycetes from sediments of Makassar Strait have been conducted. Actinomycetes is one of microbe which has an excellent track record in producing antimikrob and other active substances. But due to terrestrial actinomycetes has been widely explored, then recently researchers began focusing on wide variety of extreme environments, such as marine environment, to screening aktinomisetes in producing new secondary metabolites. A total of 36 strains of actinomycetes were isolated from 10 samples obtained from deepsea floor in Makassar Strait, Indonesia, Direct Dillution Method were best used to isolate the actinomycetes compare to Sodium Dodecyl Sulfida – Yeast Extract Method (SDS-YE Method) and Rehidration Centrifugation Method (RC Method). NBRC-802 media and Actinomycetes Isolation Agar(AIA)(Himedia)media were used as the isolation media. All the isolates were identified by morphological characteristic and by analysis of 16S rRNA gene sequence. Actinomycetes isolated from deepsea floor of Makassar Strait have been dominated by Micromonospora (58%), Verrucosispora (14%)Streptomyces (8%) and Luteipulveratus (5%), however genus Nocardiopsis, Micrococcus, Gordonia, Kytococcus, and Arthrobacter were not dominant (3%). Station 25 in 1.547 m depth was the most abundant of actinomycetes, 18 strains and dominated by the genus Micromonospora which is isolated using Direct Dillution Method and both NBRC 802 or AIA media.

scholarly journals Diversity of cultivable protease-producing bacteria and their extracellular proteases associated to scleractinian corals

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9055
Author(s):  
Hongfei Su ◽  
Zhenlun Xiao ◽  
Kefu Yu ◽  
Qinyu Huang ◽  
Guanghua Wang ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Serine Proteases ◽  
Organic Nitrogen ◽  
Vital Role ◽  
Scleractinian Corals ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
16S Rrna Gene Sequences ◽  
Extracellular Proteases ◽  
Aspartic Proteases

Protease-producing bacteria play a vital role in degrading organic nitrogen in marine environments. However, the diversity of the bacteria and extracellular proteases has seldom been addressed, especially in communities of coral reefs. In this study, 136 extracellular protease-producing bacterial strains were isolated from seven genera of scleractinian corals from Luhuitou fringing reef, and their protease types were characterized. The massive coral had more cultivable protease-producing bacteria than branching or foliose corals. The abundance of cultivable protease-producing bacteria reached 106 CFU g−1 of coral. Phylogenetic analysis of 16S rRNA gene sequences revealed that the isolates were assigned to 24 genera, from which 20 corresponded to the phyla Firmicutes and Proteobacteria. Bacillus and Fictibacillus were retrieved from all coral samples. Moreover, Vibrio and Pseudovibrio were most prevalent in massive or foliose coral Platygyra and Montipora. In contrast, 11 genera were each identified in only one isolate. Nearly all the extracellular proteases from the bacteria were serine proteases or metalloproteases; 45.83% of isolates also released cysteine or aspartic proteases. These proteases had different hydrolytic ability against different substrates. This study represents a novel insight on the diversity of cultivable protease-producing bacteria and their extracellular proteases in scleractinian corals.

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