scholarly journals Sporadic Distribution and Distinctive Variations of Cylindrospermopsin Genes in Cyanobacterial Strains and Environmental Samples from Chinese Freshwater Bodies

2014 ◽  
Vol 80 (17) ◽  
pp. 5219-5230 ◽  
Author(s):  
Yongguang Jiang ◽  
Peng Xiao ◽  
Gongliang Yu ◽  
Jihai Shao ◽  
Deming Liu ◽  
...  

ABSTRACTIncreasing reports of cylindrospermopsins (CYNs) in freshwater ecosystems have promoted the demand for identifying all of the potential CYN-producing cyanobacterial species. The present study explored the phylogenetic distribution and evolution ofcyrgenes in cyanobacterial strains and water samples from China. FourCylindrospermopsisstrains and twoRaphidiopsisstrains were confirmed to produce CYNs. MutantcyrIandcyrKgenes were observed in these strains. Clonedcyrgene sequences from eight water bodies were clustered withcyrgenes fromCylindrospermopsisandRaphidiopsis(C/R group) in the phylogenetic trees with high similarities (99%). FourcyrIsequence types and threecyrJsequence types were observed to have different sequence insertions and repeats. Phylogenetic analysis of therpoC1sequences of the C/R group revealed four conserved clades, namely, clade I, clade II, clade III, and clade V. High sequence similarities (>97%) in each clade and a divergent clade IV were observed. Therefore, CYN producers were sporadically distributed in congeneric and paraphyletic C/R group species in Chinese freshwater ecosystems. In the evolution ofcyrgenes, intragenomic translocations and intergenomic transfer between localCylindrospermopsisandRaphidiopsiswere emphasized and probably mediated by transposases. This research confirms the existence of CYN-producingCylindrospermopsisin China and reveals the distinctive variations ofcyrgenes.

2014 ◽  
Vol 64 (Pt_2) ◽  
pp. 588-593 ◽  
Author(s):  
Sooyeon Park ◽  
Ken-Chul Lee ◽  
Kyung Sook Bae ◽  
Jung-Hoon Yoon

A Gram-stain-negative, aerobic, non-spore-forming, non-flagellated, motile by gliding and rod-shaped bacterial strain, RSSK-12T, was isolated from the zone where the ocean and a freshwater spring meet at Jeju island, South Korea. Strain RSSK-12T grew optimally at 30 °C, at pH 7.0–8.0 and in the presence of 2.0–3.0 % (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain RSSK-12T clustered with the type strains of two Vitellibacter species, with which it exhibited 94.8–96.9 % sequence similarity. Sequence similarities to the type strains of species of the genus Aequorivita and of other recognized species were 94.7–95.5 % and less than 91.9 %, respectively. Strain RSSK-12T contained MK-6 as the predominant menaquinone and iso-C15 : 0 and iso-C17 : 0 3-OH as the major fatty acids. The major polar lipids of strain RSSK-12T were phosphatidylethanolamine and one unidentified lipid. The DNA G+C content of strain RSSK-12T was 38.9 mol%. Differential phenotypic properties, together with phylogenetic distinctiveness, revealed that strain RSSK-12T is separate from other Vitellibacter species. On the basis of the data presented, strain RSSK-12T is considered to represent a novel species of the genus Vitellibacter , for which the name Vitellibacter soesokkakensis sp. nov. is proposed. The type strain is RSSK-12T ( = KCTC 32536T = CECT 8398T).


2014 ◽  
Vol 64 (Pt_4) ◽  
pp. 1378-1383 ◽  
Author(s):  
Sooyeon Park ◽  
Doo-Sang Park ◽  
Kyung Sook Bae ◽  
Jung-Hoon Yoon

A Gram-reaction-negative, aerobic, non-spore-forming, non-motile and rod-shaped or ovoid bacterial strain, designated SSK6-1T, was isolated from the zone where the ocean and a freshwater spring meet at Jeju island, South Korea. Strain SSK6-1T grew optimally at 30 °C, at pH 7.0–7.5 and in the presence of 2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain SSK6-1T clustered with Phaeobacter daeponensis TF-218T and Phaeobacter caeruleus LMG 24369T, exhibiting sequence similarities of 98.6 and 98.3 %, respectively. The novel strain exhibited sequence similarities of 94.6–97.8 % to the type strains of other recognized species of the genera Phaeobacter and Leisingera . Strain SSK6-1T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and 11-methyl C18 : 1ω7c as the major fatty acids. The major polar lipids of strain SSK6-1T were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain SSK6-1T was 64.6 mol% and its DNA–DNA relatedness values with P. daeponensis TF-218T and P. caeruleus were 21 and 25 %, respectively. The differential phenotypic properties, together with phylogenetic and genetic distinctiveness, revealed that strain SSK6-1T is separate from recognized Phaeobacter species. On the basis of the data presented, strain SSK6-1T is considered to represent a novel species of the genus Phaeobacter , for which the name Phaeobacter aquaemixtae sp. nov. is proposed. The type strain is SSK6-1T ( = KCTC 32538T = CECT 8399T).


2014 ◽  
Vol 64 (Pt_12) ◽  
pp. 4068-4072 ◽  
Author(s):  
Young-Ok Kim ◽  
Sooyeon Park ◽  
Doo Nam Kim ◽  
Bo-Hye Nam ◽  
Sung-Min Won ◽  
...  

A Gram-stain-negative, aerobic, non-spore-forming, non-flagellated and rod-shaped or ovoid bacterial strain, designated RA1T, was isolated from faeces collected from Beluga whale (Delphinapterus leucas) in Yeosu aquarium, South Korea. Strain RA1T grew optimally at 25 °C, at pH 7.0–8.0 and in the presence of 2.0 % (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain RA1T joins the cluster comprising the type strains of three species of the genus Amphritea , with which it exhibited 95.8–96.0 % sequence similarity. Sequence similarities to the type strains of other recognized species were less than 94.3 %. Strain RA1T contained Q-8 as the predominant ubiquinone and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C18 : 1ω7c and C16 : 0 as the major fatty acids. The major polar lipids of strain RA1T were phosphatidylethanolamine, phosphatidylglycerol, two unidentified lipids and one unidentified aminolipid. The DNA G+C content of strain RA1T was 47.4 mol%. The differential phenotypic properties, together with the phylogenetic distinctiveness, revealed that strain RA1T is separated from other species of the genus Amphritea . On the basis of the data presented, strain RA1T is considered to represent a novel species of the genus Amphritea , for which the name Amphritea ceti sp. nov. is proposed. The type strain is RA1T ( = KCTC 42154T = NBRC 110551T).


2015 ◽  
Vol 65 (Pt_6) ◽  
pp. 1819-1824 ◽  
Author(s):  
Sooyeon Park ◽  
Ji-Min Park ◽  
Chul-Hyung Kang ◽  
Song-Gun Kim ◽  
Jung-Hoon Yoon

A Gram-stain-negative, non-motile, aerobic and pleomorphic bacterium, designated BS-W13T, was isolated from a tidal flat on the South Sea, South Korea, and its taxonomic position was investigated using a polyphasic approach. Strain BS-W13T grew optimally at 25 °C, at pH 7.0–8.0 and in the presence of 1.0–2.0 % (w/v) NaCl. Neighbour-joining and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences showed that strain BS-W13T clustered with the type strain of Seohaeicola saemankumensis , showing the highest sequence similarity (95.96 %) to this strain. Strain BS-W13T exhibited 16S rRNA gene sequence similarity values of 95.95, 95.91, 95.72 and 95.68 % to the type strains of Sulfitobacter donghicola , Sulfitobacter porphyrae , Sulfitobacter mediterraneus and Roseobacter litoralis , respectively. Strain BS-W13T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c as the major fatty acid. The polar lipid profile of strain BS-W13T, containing phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid as major components, was distinguishable from those of some phylogenetically related taxa. The DNA G+C content of strain BS-W13T was 58.1 mol%. The phylogenetic data and differential chemotaxonomic and other phenotypic properties revealed that strain BS-W13T constitutes a novel genus and species within family Rhodobacteraceae of the class Alphaproteobacteria , for which the name Pseudoseohaeicola caenipelagi gen. nov., sp. nov. is proposed. The type strain is BS-W13T ( = KCTC 42349T = CECT 8724T).


2014 ◽  
Vol 53 (1) ◽  
pp. 191-200 ◽  
Author(s):  
Walter Demczuk ◽  
Tarah Lynch ◽  
Irene Martin ◽  
Gary Van Domselaar ◽  
Morag Graham ◽  
...  

A large-scale, whole-genome comparison of CanadianNeisseria gonorrhoeaeisolates with high-level cephalosporin MICs was used to demonstrate a genomic epidemiology approach to investigate strain relatedness and dynamics. Although current typing methods have been very successful in tracing short-chain transmission of gonorrheal disease, investigating the temporal evolutionary relationships and geographical dissemination of highly clonal lineages requires enhanced resolution only available through whole-genome sequencing (WGS). Phylogenomic cluster analysis grouped 169 Canadian strains into 12 distinct clades. While someN. gonorrhoeaemultiantigen sequence types (NG-MAST) agreed with specific phylogenomic clades or subclades, other sequence types (ST) and closely related groups of ST were widely distributed among clades. Decreased susceptibility to extended-spectrum cephalosporins (ESC-DS) emerged among a group of diverse strains in Canada during the 1990s with a variety of nonmosaicpenAalleles, followed in 2000/2001 with thepenAmosaic X allele and then in 2007 with ST1407 strains with thepenAmosaic XXXIV allele. Five genetically distinct ESC-DS lineages were associated withpenAmosaic X, XXXV, and XXXIV alleles and nonmosaic XII and XIII alleles. ESC-DS with coresistance to azithromycin was observed in 5 strains with 23S rRNA C2599T or A2143G mutations. As the costs associated with WGS decline and analysis tools are streamlined, WGS can provide a more thorough understanding of strain dynamics, facilitate epidemiological studies to better resolve social networks, and improve surveillance to optimize treatment for gonorrheal infections.


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 ◽  
...  

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%.


2015 ◽  
Vol 65 (Pt_5) ◽  
pp. 1622-1627 ◽  
Author(s):  
Zhi-Ping Zhong ◽  
Ying Liu ◽  
Ting-Ting Hou ◽  
Yu-Guang Zhou ◽  
Hong-Can Liu ◽  
...  

A Gram-staining-negative bacterium, strain TS-T86T, was isolated from Lake Tuosu, a saline lake (salinity 5.4 %, w/w) in Qaidam basin, China. Its taxonomic position was determined by using a polyphasic approach. Strain TS-T86T was strictly heterotrophic, aerobic and catalase- and oxidase-positive. Cells were non-spore-forming, non-motile rods, 0.4–0.6 µm wide and 1.2–2.3 µm long. Growth was observed in the presence of 0–9.0 % (w/v) NaCl (optimum, 2.0 %), at 4–35 °C (optimum, 25 °C) and at pH 7.0–10.5 (optimum, pH 8.5–9.0). Strain TS-T86T contained MK-7 as the predominant respiratory quinone. The major fatty acids (>10 %) were iso-C15 : 1 G, iso-C15 : 0, iso-C17 : 1ω9c, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The polar lipids consisted of phosphatidylethanolamine, an unknown phospholipid, six unidentified aminolipids and two uncharacterized lipids. The DNA G+C content was 35 mol% (T m). Phylogenetic trees based on 16S rRNA gene sequences showed that strain TS-T86T was associated with the genus Belliella , and showed the highest sequence similarity to Belliella baltica BA134T (98.5 %) and then to Belliella kenyensis No.164T (95.7 %) and Belliella pelovolcani CC-SAL-25T (95.3 %). DNA–DNA relatedness of strain TS-T86T to Belliella baltica DSM 15883T was 32±3 %. It is concluded that strain TS-T86T represents a novel species of the genus Belliella , for which the name Belliella aquatica sp. nov. is proposed. The type strain is TS-T86T ( = CGMCC 1.12479T = JCM 19468T).


2012 ◽  
Vol 78 (12) ◽  
pp. 4420-4433 ◽  
Author(s):  
Brian D. Sauders ◽  
Jon Overdevest ◽  
Esther Fortes ◽  
Katy Windham ◽  
Ynte Schukken ◽  
...  

ABSTRACTA total of 442Listeriaisolates, including 234Listeria seeligeri, 80L. monocytogenes, 74L. welshimeri, 50L. innocua, and 4L. marthiiisolates, were obtained from 1,805 soil, water, and other environmental samples collected over 2 years from four urban areas and four areas representing natural environments.Listeriaspp. showed similar prevalences in samples from natural (23.4%) and urban (22.3%) environments. WhileL. seeligeriandL. welshimeriwere significantly associated with natural environments (P≤ 0.0001),L. innocuaandL. monocytogeneswere significantly associated with urban environments (P≤ 0.0001). Sequencing ofsigBfor all isolates revealed 67 allelic types with a higher level of allelic diversity among isolates from urban environments. SomeListeriaspp. andsigBallelic types showed significant associations with specific urban and natural areas. Nearest-neighbor analyses also showed that certainListeriaspp. andsigBallelic types were spatially clustered within both natural and urban environments, and there was evidence that these species and allelic types persisted over time in specific areas. Our data show that members of the genusListerianot only are common in urban and natural environments but also show species- and subtype-specific associations with different environments and areas. This indicates thatListeriaspecies and subtypes within these species may show distinct ecological preferences, which suggests (i) that molecular source-tracking approaches can be developed forListeriaand (ii) that detection of someListeriaspecies may not be a good indicator forL. monocytogenes.


Author(s):  
Shan Jiang ◽  
Feng-Bai Lian ◽  
You-Yang Sun ◽  
Xiao-Kui Zhang ◽  
Zong-Jun Du

A Gram-stain-negative, rod-shaped and facultatively aerobic bacterial strain, designated F7430T, was isolated from coastal sediment collected at Jingzi Wharf in Weihai, PR China. Cells of strain F7430T were 0.3–0.4 µm wide, 2.0–2.6 µm long, non-flagellated, non-motile and formed pale-beige colonies. Growth was observed at 4–40 °C (optimum, 30 °C), pH 6.0–9.0 (optimum, pH 7.5–8.0) and at NaCl concentrations of 1.0–10.0 % (w/v; optimum, 1.0 %). The sole respiratory quinone of strain F7430T was ubiquinone 8 and the predominant cellular fatty acids were summed feature 8 (C18 : 1  ω7c / C18 : 1  ω6c; 60.7 %), summed feature 3 (C16 : 1  ω7c/C16 : 1  ω6c; 30.2 %) and C15 : 0 iso (13.9 %). The polar lipids of strain F7430T consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, one unidentified phospholipid and three unidentified lipids. Results of 16S rRNA gene sequences analyses indicated that this strain belonged to the family Halieaceae and had high sequence similarities to Parahaliea aestuarii JCM 51547T (95.3 %) and Halioglobus pacificus DSM 27932T (95.2 %) followed by 92.9–95.0 % sequence similarities to other type species within the aforementioned family. The rpoB gene sequences analyses indicated that the novel strain had the highest sequence similarities to Parahaliea aestuarii JCM 51547T (82.2 %) and Parahaliea mediterranea DSM 21924T (82.2 %) followed by 75.2–80.5 % sequence similarities to other type species within this family. Phylogenetic analyses showed that strain F7430T constituted a monophyletic branch clearly separated from the other genera of family Halieaceae . Whole-genome sequencing of strain F7430T revealed a 3.3 Mbp genome size with a DNA G+C content of 52.6 mol%. The genome encoded diverse metabolic pathways including the Entner–Doudoroff pathway, assimilatory sulphate reduction and biosynthesis of dTDP-l-rhamnose. Based on results from the current polyphasic study, strain F7430T is proposed to represent a novel species of a new genus within the family Halieaceae , for which the name Sediminihaliea albiluteola gen. nov., sp. nov. is proposed. The type strain of the type species is F7430T (=KCTC 72873T=MCCC 1H00420T).


2016 ◽  
Vol 61 (1) ◽  
Author(s):  
Felipe Lira de Sá Cavalcanti ◽  
Carina Lucena Mendes-Marques ◽  
Crhisllane Rafaele dos Santos Vasconcelos ◽  
Túlio de Lima Campos ◽  
Antonio Mauro Rezende ◽  
...  

ABSTRACT Here, we report the isolation of 31 Acinetobacter baumannii strains producing OXA-253 in a single large Brazilian city. These strains belonged to five different sequence types (STs), including 4 STs not previously associated with bla OXA-253. In all strains, the bla OXA-253 gene was located in a plasmid within a genetic environment similar to what was found previously in Brazil and Italy. The reported data emphasize the successful transmission of the bla OXA-253 gene through a large area and the tendency for this resistance determinant to remain in the A. baumannii population.


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