scholarly journals Biodiversity of new lytic bacteriophages infecting Shigella spp. in fresh water environment

2020 ◽  
Author(s):  
Khashayar Shahin ◽  
Mohadeseh Barazandeh ◽  
Abolghasem Hedayatkhah ◽  
Mojtaba Mansoorianfar ◽  
Ran Wang
Keyword(s):  
Phylogenetic Analyses ◽  
Water Environment ◽  
Life Forms ◽  
Bacterial Host ◽  
E Coli ◽  
Major Subject ◽  
Shigella Spp ◽  
Almost All ◽  
Myoviridae Family ◽  
Fresh Water Environment

Abstract Background Bacteriophages, viruses that infects and replicates within prokaryotic cells are the most abundant life forms in the environment, yet the vast majority of them have not been properly reported or even discovered. Almost all reported bacteriophages infecting the Enterobacteriaceae family, with E. coli being the major subject of the study, have been isolated from wastewater, sewage, and effluent resources. In the present study we focused on the distribution and biodiversity of Shigella phages in an aquatic ecosystem. Results While no Shigella bacteria was recovered from the Yangtze River, three lytic phages were isolated from this ecosystem and were subjected to biological, morphological, and genomic characteristics. Comparative genomics and phylogenetic analyses demonstrated that vB _SflM_004 isolate belongs to Myoviridae family, Felixounavirus genus of Ounavirinae subfamily, vB_SdyM_006 was classified under the same family, however, it is suggested to be in a new genus under Tevenvirinae subfamily with some other related bacteriophages. vB_SsoS_008 phage belongs to the Siphoviridae family, Tunavirus genus, Tunavirinae subfamily. The phages did not harbor any genes involved in the lysogenic cycles, and showed a high temperature and pH stability. Conclusions It can be concluded that isolation of bacteriophages could be independent of their bacterial host presence in the isolation environment.

scholarly journals Biodiversity of New Lytic Bacteriophages Infecting Shigella spp. in Freshwater Environment

2021 ◽  
Vol 12 ◽  
Author(s):  
Khashayar Shahin ◽  
Mohadeseh Barazandeh ◽  
Lili Zhang ◽  
Abolghasem Hedayatkhah ◽  
Tao He ◽  
...  
Keyword(s):  
Yangtze River ◽  
New Genus ◽  
Phylogenetic Analyses ◽  
Life Forms ◽  
Aquatic Environments ◽  
The Yangtze River ◽  
Freshwater Environment ◽  
Major Subject ◽  
Shigella Spp ◽  
Almost All

Bacteriophages, viruses that infect and replicate within prokaryotic cells are the most abundant life forms in the environment, yet the vast majority of them have not been properly reported or even discovered. Almost all reported bacteriophages infecting the Enterobacteriaceae family, with Escherichia coli being the major subject of studies, have been isolated from wastewater, sewage, and effluent resources. In the present study, we focused on the distribution and biodiversity of Shigella phages in an aquatic ecosystem. While no Shigella bacteria was recovered from the Yangtze River, three lytic phages were isolated from this ecosystem and were subjected to biological, morphological, and genomic characteristics. Comparative genomics and phylogenetic analyses demonstrated that vB _SflM_004 isolate belongs to Myoviridae family, Felixounavirus genus of Ounavirinae subfamily, vB_SdyM_006 was classified under the same family, however, it is suggested to be in a new genus under Tevenvirinae subfamily with some other related bacteriophages. vB_SsoS_008 phage belongs to the Siphoviridae family, Tunavirus genus, Tunavirinae subfamily. The phages did not harbor any genes involved in the lysogenic cycles and showed a high temperature and pH stability. The biodiversity of the isolated phages highly suggests that continued isolation on non-model members of Enterobacteriaceae family is necessary to fully understand bacteriophage diversity in aquatic environments.

The Characterization of Antibiotic Resistance of Bacterial Isolates from Intensive Care Unit Patient Samples in a University Affiliated Hospital in Romania

2019 ◽  
Vol 70 (5) ◽  
pp. 1778-1783
Author(s):  
Andreea-Loredana Golli ◽  
Floarea Mimi Nitu ◽  
Maria Balasoiu ◽  
Marina Alina Lungu ◽  
Cristiana Cerasella Dragomirescu ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Resistance ◽  
Bacterial Pathogens ◽  
Resistance Rate ◽  
Resistance Pattern ◽  
Bacterial Isolates ◽  
E Coli ◽  
Acinetobacter Spp ◽  
Almost All ◽  
Klebsiella Spp

To determine the resistance pattern of bacterial pathogens involved in infections of the patients aged between 18-64 years, admitted in a ICU from a 1518-bed university-affiliated hospital. A retrospective study of bacterial pathogens was carried out on 351 patients aged between 18-64 years admitted to the ICU, from January to December 2017. In this study there were analysed 469 samples from 351 patients (18-64 years). A total of 566 bacterial isolates were obtained, of which 120 strains of Klebsiella spp. (35.39%%), followed by Nonfermenting Gram negative bacilli, other than Pseudomonas and Acinetobacter (NFB) (75- 22.12%), Acinetobacter spp. (53 - 15.63%), Pseudomonas aeruginosa and Proteus (51 - 15.04%), and Escherichia coli (49 - 14.45%). The most common isolates were from respiratory tract (394 isolates � 69.61%). High rates of MDR were found for Pseudomonas aeruginosa (64.70%), MRSA (62.65%) and Klebsiella spp. (53.33%), while almost all of the isolated NFB strains were MDR (97.33%). There was statistic difference between the drug resistance rate of Klebsiella and E. coli strains to ceftazidime and ceftriaxone (p[0.001), cefuroxime (p[0.01) and to cefepime (p[0.01). The study revealed an alarming pattern of antibiotic resistance in the majority of ICU isolates.

scholarly journals Phylogenetic Grouping and Virulence Potential of Extended-Spectrum-β-Lactamase-Producing Escherichia coli Strains in Cattle

2012 ◽  
Vol 78 (13) ◽  
pp. 4677-4682 ◽  
Author(s):  
Charlotte Valat ◽  
Frédéric Auvray ◽  
Karine Forest ◽  
Véronique Métayer ◽  
Emilie Gay ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Determinants ◽  
Phylogenetic Groups ◽  
Content Type ◽  
E Coli ◽  
Extended Spectrum ◽  
Specific Distribution ◽  
Extended Spectrum Beta Lactamases ◽  
Phylogenetic Grouping ◽  
Almost All

ABSTRACTIn line with recent reports of extended-spectrum beta-lactamases (ESBLs) inEscherichia coliisolates of highly virulent serotypes, such as O104:H4, we investigated the distribution of phylogroups (A, B1, B2, D) and virulence factor (VF)-encoding genes in 204 ESBL-producingE. coliisolates from diarrheic cattle. ESBL genes, VFs, and phylogroups were identified by PCR and a commercial DNA array (Alere, France). ESBL genes belonged mostly to the CTX-M-1 (65.7%) and CTX-M-9 (27.0%) groups, whereas those of the CTX-M-2 and TEM groups were much less represented (3.9% and 3.4%, respectively). One ESBL isolate wasstx1andeaepositive and belonged to a major enterohemorrhagicE. coli(EHEC) serotype (O111:H8). Two other isolates wereeaepositive butstxnegative; one of these had serotype O26:H11. ESBL isolates belonged mainly to phylogroup A (55.4%) and, to lesser extents, to phylogroups D (25.5%) and B1 (15.6%), whereas B2 strains were quasi-absent (1/204). The number of VFs was significantly higher in phylogroup B1 than in phylogroups A (P= 0.04) and D (P= 0.02). Almost all of the VFs detected were found in CTX-M-1 isolates, whereas only 64.3% and 33.3% of them were found in CTX-M-9 and CTX-M-2 isolates, respectively. These results indicated that the widespread dissemination of theblaCTX-Mgenes within theE. colipopulation from cattle still spared the subpopulation of EHEC/Shiga-toxigenicE. coli(STEC) isolates. In contrast to other reports on non-ESBL-producing isolates from domestic animals, B1 was not the main phylogroup identified. However, B1 was found to be the most virulent phylogroup, suggesting host-specific distribution of virulence determinants among phylogenetic groups.

scholarly journals Antibacterial activity of ginger extracts on bacteria isolated from digestive tract infection patients attended Muhoza Health Center

2020 ◽  
Vol 11 (2) ◽  
pp. 35-41
Author(s):  
Callixte Yadufashije ◽  
Adolyne Niyonkuru ◽  
Emanuel Munyeshyaka ◽  
Sibomana Madjidi ◽  
Joseph Mucumbitsi
Keyword(s):  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Tract Infection ◽  
Health Center ◽  
Digestive Tract ◽  
Inhibition Zone ◽  
Ginger Extract ◽  
E Coli ◽  
Shigella Spp ◽  
Stool Samples

Background: Ginger (Zingiber officinale) has been used for long time due to its potential antimicrobial activity against diversity of microbial pathogens. Aims and Objectives: The study was carried out to investigate the bacteria pathogens found in digestive tract infections and assess antimicrobial activities of ginger extract to identified bacteria. Materials and Methods: Bacteriological studies were carried out on stool samples from 30 patients attending Muhoza health center. Different types of bacteria were isolated from stool samples of digestive tract infection patients by using various methods such culture, biochemical test and antimicrobial activity of ginger extracts was analyzed at INES-Ruhengeri in clinical microbiology laboratory. Results: Study findings showed isolated bacteria and antibacterial activity of Ginger. Isolated bacteria and their percentages including Escherichia coli (46.6%) which is the predominant isolated bacteria, Salmonella species (33.33%), Enterobacter spp (10.0%), Shigella spp (6.6%) and Citrobacter (3.33%) which is the least isolated bacteria. Antibacterial activity of ginger was seen on isolated bacteria, as ethanol and methanol were used for ginger oil extraction, the antibacterial activity of ginger extracts using ethanol was seen on isolated bacteria such us Citrobacter spp with 14 mm of inhibition zone, Shigella spp with 12 mm, Salmonella with 11.1 mm, E. coli with 9.5 mm and Enterobacter spp which was seen to be resistant to ginger extract using ethanol with 0.66mm of inhibition zone. For methanol extracts antibacterial activity was seen as follows: Citrobacter spp at 12 mm, Shigella spp at 11 mm, E. coli at 8 mm, salmonella spp at 6.1 mm, and Enterobacter spp with 5 mm. Enterobacter spp was seen to be the most resistant bacteria in both extracts. Conclusion: Ginger has shown to have an antibacterial activity on bacteria isolated from digestive tract infected patients. It can be used as a medicine to treat these infections. Number of researches should be done to be sure on this reality of antibacterial activity of ginger.

scholarly journals Dinucleoside polyphosphates act as 5’-RNA caps in Escherichia coli

2019 ◽  
Author(s):  
Oldřich Hudeček ◽  
Roberto Benoni ◽  
Martin Culka ◽  
Martin Hubálek ◽  
Lubomír Rulíšek ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Rna Stability ◽  
E Coli ◽  
Chemical Structures ◽  
Additional Layer ◽  
Similar Chemical ◽  
Decapping Enzyme ◽  
Almost All ◽  
Dinucleoside Polyphosphates ◽  
Rna Caps

Dinucleoside polyphosphates (NpnNs), discovered more than 50 years ago,1 are pleiotropic molecules present in almost all types of cells.2 It has been shown that their intracellular concentration can under stress conditions increase from the µM to mM range 2,3. However, the cellular roles and mechanisms of action of NpnNs are still speculative4,5. They have never been considered as part of the RNA, even though they have similar chemical structures as already known RNA caps, such as the nicotinamide adenine dinucleotide (NAD)6-8 and 7-methylguanylate cap9. Here, we show that both methylated and non-methylated Npn Ns serve as RNA caps in Escherichia coli (E. coli). NpnNs are excellent substrates for T7 and E. coli RNA polymerases (RNAP) and efficiently initiate transcription. Further, we demonstrate that the E. coli decapping enzyme RNA 5’ pyrophosphohydrolase (RppH) is able to remove the NpnNs-cap from the RNA. RppH was, however, not able to cleave the methylated forms of the NpnN-caps, suggesting that the methylation adds an additional layer to the RNA stability regulation. Our work introduces an original perspective on the chemical structure of RNA in prokaryotes and the function of RNA caps. This is the first evidence that small molecules like NpnNs can act in cells via their incorporation into RNA and influence the cellular metabolism.

scholarly journals CMOS-based Image Cytometry for Detection of Phytoplankton in Ballast Water

2017 ◽  
Author(s):  
M Jofre ◽  
J M Perez ◽  
P Martinez ◽  
Z Moubarak ◽  
C Hurth ◽  
...  
Keyword(s):  
The Netherlands ◽  
Ballast Water ◽  
Wadden Sea ◽  
Limit Of Detection ◽  
Water Environment ◽  
Image Cytometry ◽  
Marine Water ◽  
Pam Fluorometry ◽  
Ballast Water Treatment Systems ◽  
Fresh Water Environment

An image cytometer (CYT) for the analysis of phytoplankton in fresh and marine water environments is introduced. A linear quantification of the number of cells over several orders of magnitude of concentrations was observed using cultures of Tetraselmis and Nannochloropsis measured by autofluorescence of the chlorophyll in a laboratory environment. The functionality of the system outside the laboratory was analysed by phytoplankton quantification of samples taken from marine water environment (Dutch Wadden Sea, The Netherlands) and fresh water environment (Lake Ijssel, The Netherlands). The CYT was also employed to study the effects of two ballast water treatment systems (BWTS), based on chlorine electrolysis and UV sterilisation by determining the vitality of the phytoplankton. In order to ensure the detection limit, a large volume (1l) of samples was collected and concentrated to 3 ml using CelltrapTM filters. The results were compared to benchmarked flow cytometer and PAM Fluorometry at Marine Eco-Analytics (MEA-NL). The image cytometer reached a 10 cells/ml limit of detection (LoD) with an accuracy between 0.7 and 0.5 log, and a correlation of 88.29% in quantification and 96.21% in vitality, when compared to benchmarked monitoring techniques.

scholarly journals "Mineralogical & Petrographic Microfacies Study of the Zahraa formation (Pliocene– Pleistocene) in Sawa Lake Surrounding area- IRAQ "

2017 ◽  
Vol 4 (1) ◽  
pp. 11-20
Author(s):  
Saleh A. Lazam
Keyword(s):  
Organic Matter ◽  
Fresh Water ◽  
Depositional Environment ◽  
Water Environment ◽  
Lake Area ◽  
Surrounding Area ◽  
Thin Sections ◽  
Project Area ◽  
Mineralogical Study ◽  
Fresh Water Environment

"Mineralogical, Petorographic Microfacies study has been done on (16) samples of Zahraa formation (Pliocene – Pleistocene) of outcrop in Surrounded Sawa Lake area. The mineralogical study showed that Calcite is the main mineral within the rock formation, whereas the upper rocks of Zahraa Formation consist silty or sandy claystone is dominant in the middle and the upper portion, in addition to quartz, clay minerals, iron oxide and organic matter as insoluble residues. From thin sections study, Three main microfacies have been identified which are: Charophyte shelly bioclastic wackestone, Charophyte shelly bioclastic dolowackestone and Algal wackestone. Based on microfacies study and its fossils content, it has been possible to determine the depositional environment of Zahraa Formation which deposits in the area of the presence of Charaphytes, indicates fresh water environment. From the depositioal situation and the large extension in the project area, the type of fresh water environment is ephemeral freshen water lakes."

scholarly journals Subcellular location and properties of bactericidal factors from human neutrophils.

1986 ◽  
Vol 164 (5) ◽  
pp. 1407-1421 ◽  
Author(s):  
J E Gabay ◽  
J M Heiple ◽  
Z A Cohn ◽  
C F Nathan
Keyword(s):  
Protein S ◽  
Subcellular Location ◽  
Inhibitory Effect ◽  
Human Neutrophils ◽  
E Coli ◽  
Fractionation Scheme ◽  
Percoll Gradients ◽  
Nonionic Detergent ◽  
Almost All ◽  
Triton X

We examined the subcellular location of bactericidal factors (BF) in human neutrophils, using an efficient fractionation scheme. Nitrogen bomb cavitates of DIFP-treated PMN were centrifuged through discontinuous Percoll gradients, each fraction extracted with 0.05 M glycine, pH 2.0, and tested for the killing of Escherichia coli. greater than 90% of BF coisolated with the azurophil granules. After lysis of azurophils, 98% of azurophil-derived BF (ADBF) sedimented with the membrane. ADBF activity was solubilized from azurophil membrane with either acid or nonionic detergent (Triton X-100, Triton X-114). Bactericidal activity was linear with respect to protein concentration over the range 0.3-30 micrograms/ml. 0.1-0.3 microgram/ml ADBF killed 10(5) E. coli within 30 min at 37 degrees C. At 1.4 micrograms/ml, 50% of 2 X 10(5) bacteria were killed within 5 min. ADBF was effective between pH 5-8, with peak activity at pH 5.5. Glucose (20 mM), EDTA (1-25 mM), and physiologic concentrations of NaCl or KCl had little or no inhibitory effect on ADBF. ADBF killed both Gram-positive and Gram-negative virulent clinical isolates, including listeria, staphylococci, beta-hemolytic streptococci, and Pseudomonas aeruginosa. Thus, under these conditions of cell disruption, fractionation, extraction, and assay, almost all BF in human PMN appeared to be localized to the membrane of azurophilic granules as a highly potent, broad-spectrum, rapidly acting protein(s) effective in physiologic medium. Some of these properties appear to distinguish ADBF from previously described PMN bactericidal proteins.

scholarly journals Antibacterial Potential of the Methanol Stem Bark Extract of Stachytarpheta Indica

2013 ◽  
Vol 4 (4) ◽  
pp. 5-10
Author(s):  
Christian Godwin Akuodor ◽  
Monday Pius Udia ◽  
Charles Emeka Udenze ◽  
John Onyemaechi Ogbonna
Keyword(s):  
Antimicrobial Agents ◽  
Medical Science ◽  
Stem Bark ◽  
Bark Extract ◽  
Significant Activity ◽  
E Coli ◽  
Diffusion Technique ◽  
Shigella Spp ◽  
Test Organisms ◽  
Stem Bark Extract

Objective: There is increasing need for potent antimicrobial agents to tackle the problem of diseases in man. In view of this, the activities of methanol stem bark extract of Stachytarpheta indica was evaluated against some disease causing microorganisms. Method: The activity of the extract against S. aureus, P.aeruginosa, E. coli, S. typhi and Shigella spp was determined using agar diffusion technique. Results: The methanol stem bark extract demonstrated significant activity against the test organisms. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the stem bark extract ranged from 12-60 μg/ml. Conclusion: Further isolation of active compound responsible for the antibacterial activity could be the potential sources of new antibacterial agents. Asian Journal of Medical Science, Volume-4 (2013), Pages 5-10 DOI: http://dx.doi.org/10.3126/ajms.v4i4.8248 

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