The Bacillus subtilisNucleotidyltransferase Is a tRNA CCA-Adding Enzyme

ABSTRACT There has been increased interest in bacterial polyadenylation with the recent demonstration that 3′ poly(A) tails are involved in RNA degradation. Poly(A) polymerase I (PAP I) of Escherichia coli is a member of the nucleotidyltransferase (Ntr) family that includes the functionally related tRNA CCA-adding enzymes. Thirty members of the Ntr family were detected in a search of the current database of eubacterial genomic sequences. Gram-negative organisms from the β and γ subdivisions of the purple bacteria have two genes encoding putative Ntr proteins, and it was possible to predict their activities as either PAP or CCA adding by sequence comparisons with theE. coli homologues. Prediction of the functions of proteins encoded by the genes from more distantly related bacteria was not reliable. The Bacillus subtilis papS gene encodes a protein that was predicted to have PAP activity. We have overexpressed and characterized this protein, demonstrating that it is a tRNA nucleotidyltransferase. We suggest that the papS gene should be renamed cca, following the notation for itsE. coli counterpart. The available evidence indicates thatcca is the only gene encoding an Ntr protein, despite previous suggestions that B. subtilis has a PAP similar toE. coli PAP I. Thus, the activity involved in RNA 3′ polyadenylation in the gram-positive bacteria apparently resides in an enzyme distinct from its counterpart in gram-negative bacteria.

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Synthesis of Chalcones and Nucleosides Incorporating [1, 3, 4]Oxadiazolenone Core and Evaluation of their Antifungal and Antibacterial Activities

Current Bioactive Compounds ◽

10.2174/1573407214666180911130110 ◽

2020 ◽

Vol 15 (6) ◽

pp. 665-679

Author(s):

Alok K. Srivastava ◽

Lokesh K. Pandey

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Bacillus Subtilis ◽

Antifungal Activity ◽

Aspergillus Niger ◽

Gram Negative ◽

E Coli ◽

Gram Positive Bacteria ◽

Good Antibacterial Activity

Background: [1, 3, 4]oxadiazolenone core containing chalcones and nucleosides were synthesized by Claisen-Schmidt condensation of a variety of benzaldehyde derivatives, obtained from oxidation of substituted 5-(3/6 substituted-4-Methylphenyl)-1, 3, 4-oxadiazole-2(3H)-one and various substituted acetophenone. The resultant chalcones were coupled with penta-O-acetylglucopyranose followed by deacetylation to get [1, 3, 4] oxadiazolenone core containing chalcones and nucleosides. Various analytical techniques viz IR, NMR, LC-MS and elemental analysis were used to confirm the structure of the synthesised compounds.The compounds were targeted against Bacillus subtilis, Staphylococcus aureus and Escherichia coli for antibacterial activity and Aspergillus flavus, Aspergillus niger and Fusarium oxysporum for antifungal activity. Methods: A mixture of Acid hydrazides (3.0 mmol) and N, Nʹ- carbonyl diimidazole (3.3 mmol) in 15 mL of dioxane was refluxed to afford substituted [1, 3, 4]-oxadiazole-2(3H)-one. The resulted [1, 3, 4]- oxadiazole-2(3H)-one (1.42 mmol) was oxidized with Chromyl chloride (1.5 mL) in 20 mL of carbon tetra chloride and condensed with acetophenones (1.42 mmol) to get chalcones 4. The equimolar ratio of obtained chalcones 4 and β -D-1,2,3,4,6- penta-O-acetylglucopyranose in presence of iodine was refluxed to get nucleosides 5. The [1, 3, 4] oxadiazolenone core containing chalcones 4 and nucleosides 5 were tested to determined minimum inhibitory concentration (MIC) value with the experimental procedure of Benson using disc-diffusion method. All compounds were tested at concentration of 5 mg/mL, 2.5 mg/mL, 1.25 mg/mL, 0.62 mg/mL, 0.31 mg/mL and 0.15 mg/mL for antifungal activity against three strains of pathogenic fungi Aspergillus flavus (A. flavus), Aspergillus niger (A. niger) and Fusarium oxysporum (F. oxysporum) and for antibacterial activity against Gram-negative bacterium: Escherichia coli (E. coli), and two Gram-positive bacteria: Staphylococcus aureus (S. aureus) and Bacillus subtilis(B. subtilis). Result: The chalcones 4 and nucleosides 5 were screened for antibacterial activity against E. coli, S. aureus and B. subtilis whereas antifungal activity against A. flavus, A. niger and F. oxysporum. Compounds 4a-t showed good antibacterial activity whereas compounds 5a-t containing glucose moiety showed better activity against fungi. The glucose moiety of compounds 5 helps to enter into the cell wall of fungi and control the cell growth. Conclusion: Chalcones 4 and nucleosides 5 incorporating [1, 3, 4] oxadiazolenone core were synthesized and characterized by various spectral techniques and elemental analysis. These compounds were evaluated for their antifungal activity against three fungi; viz. A. flavus, A. niger and F. oxysporum. In addition to this, synthesized compounds were evaluated for their antibacterial activity against gram negative bacteria E. Coli and gram positive bacteria S. aureus, B. subtilis. Compounds 4a-t showed good antibacterial activity whereas 5a-t showed better activity against fungi.

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Linearized esculentin-2EM shows pH dependent antibacterial activity with an alkaline optimum

Molecular and Cellular Biochemistry ◽

10.1007/s11010-021-04181-7 ◽

2021 ◽

Author(s):

Erum Malik ◽

David A. Phoenix ◽

Timothy J. Snape ◽

Frederick Harris ◽

Jaipaul Singh ◽

...

Keyword(s):

Helical Structure ◽

Food Preservation ◽

Forming Process ◽

Gram Positive ◽

Gram Negative ◽

Bacterial Membranes ◽

Gram Positive Bacteria ◽

Alkaline Conditions ◽

Ph Dependent ◽

Gram Negative Organisms

AbstractHere the hypothesis that linearized esculentin 2EM (E2EM-lin) from Glandirana emeljanovi possesses pH dependent activity is investigated. The peptide showed weak activity against Gram-negative bacteria (MLCs ≥ 75.0 μM) but potent efficacy towards Gram-positive bacteria (MLCs ≤ 6.25 μM). E2EM-lin adopted an α-helical structure in the presence of bacterial membranes that increased as pH was increased from 6 to 8 (↑ 15.5–26.9%), whilst similar increases in pH enhanced the ability of the peptide to penetrate (↑ 2.3–5.1 mN m−1) and lyse (↑ 15.1–32.5%) these membranes. Theoretical analysis predicted that this membranolytic mechanism involved a tilted segment, that increased along the α-helical long axis of E2EM-lin (1–23) in the N → C direction, with − < µH > increasing overall from circa − 0.8 to − 0.3. In combination, these data showed that E2EM-lin killed bacteria via novel mechanisms that were enhanced by alkaline conditions and involved the formation of tilted and membranolytic, α-helical structure. The preference of E2EM-lin for Gram-positive bacteria over Gram-negative organisms was primarily driven by the superior ability of phosphatidylglycerol to induce α-helical structure in the peptide as compared to phosphatidylethanolamine. These data were used to generate a novel pore-forming model for the membranolytic activity of E2EM-lin, which would appear to be the first, major reported instance of pH dependent AMPs with alkaline optima using tilted structure to drive a pore-forming process. It is proposed that E2EM-lin has the potential for development to serve purposes ranging from therapeutic usage, such as chronic wound disinfection, to food preservation by killing food spoilage organisms.

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Endotoxemia as a Diagnostic Tool for Patients with Suspected Bacteremia Caused by Gram-Negative Organisms: a Meta-Analysis of 4 Decades of Studies

Journal of Clinical Microbiology ◽

10.1128/jcm.03531-14 ◽

2015 ◽

Vol 53 (4) ◽

pp. 1183-1191 ◽

Cited By ~ 13

Author(s):

James C. Hurley ◽

Piotr Nowak ◽

Lars Öhrmalm ◽

Charalambos Gogos ◽

Apostolos Armaganidis ◽

...

Keyword(s):

Confidence Interval ◽

Meta Analysis ◽

Inclusion Criteria ◽

Summary Receiver Operating Characteristic ◽

Detection Rates ◽

Gram Negative ◽

Content Type ◽

E Coli ◽

Patient Groups ◽

Gram Negative Organisms

The clinical significance of endotoxin detection in blood has been evaluated for a broad range of patient groups in over 40 studies published over 4 decades. The influences of Gram-negative (GN) bacteremia species type and patient inclusion criteria on endotoxemia detection rates in published studies remain unclear. Studies were identified after a literature search and manual reviews of article bibliographies, together with a direct approach to authors of potentially eligible studies for data clarifications. The concordance between GN bacteremia and endotoxemia expressed as the summary diagnostic odds ratios (DORs) was derived for three GN bacteremia categories across eligible studies by using a hierarchical summary receiver operating characteristic (HSROC) method. Forty-two studies met broad inclusion criteria, with between 2 and 173 GN bacteremias in each study. Among all 42 studies, the DORs (95% confidence interval) were 3.2 (1.7 to 6.0) and 5.8 (2.4 to 13.7) in association with GN bacteremias withEscherichia coliand those withPseudomonas aeruginosa, respectively. Among 12 studies of patients with sepsis, the proportion of endotoxemia positivity (95% confidence interval) among patients withP. aeruginosabacteremia (69% [57 to 79%];P= 0.004) or withProteusbacteremia (76% [51 to 91%];P= 0.04) was significantly higher than that among patients without GN bacteremia (49% [33 to 64%]), but this was not so for patients bacteremic withE. coli(57% [40 to 73%];P= 0.55). Among studies of the sepsis patient group, the concordance of endotoxemia with GN bacteremia was surprisingly weak, especially forE. coliGN bacteremia.

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An unusual case of chest pain

International Journal of Advances in Medicine ◽

10.18203/2349-3933.ijam20203131 ◽

2020 ◽

Vol 7 (8) ◽

pp. 1290

Author(s):

Saswat Subhankar ◽

K. Madhuri ◽

Vivek D. Alone

Keyword(s):

Staphylococcus Aureus ◽

Developing Countries ◽

Chest Pain ◽

Unusual Case ◽

Gram Negative Bacteria ◽

Pleural Effusions ◽

Gram Negative ◽

Competent Patient ◽

E Coli ◽

Gram Positive Bacteria

Osteomyelitis is an infection of the bones caused by pyogenic organisms. The ribs are an extremely uncommon site for osteomyelitis, occurring in less than 1% cases. The main causative organisms are Gram-positive bacteria, such as Staphylococcus aureus and Hemophilus influenzae. Gram-negative bacteria like E. coli have been rarely reported. Authors hereby present a case of an immune-competent patient who presented with an osteomyelitis of the ribs caused by the latter. In developing countries, tuberculosis is considered as the primary cause of osteomyelitis and pleural effusions. However, other organisms should also be considered in patients who present with fulminant infections.

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Construction of Leaderless-Bacteriocin-Producing Bacteriophage Targeting E. coli and Neighboring Gram-Positive Pathogens

Microbiology Spectrum ◽

10.1128/spectrum.00141-21 ◽

2021 ◽

Author(s):

Yoshimitsu Masuda ◽

Shun Kawabata ◽

Tatsuya Uedoi ◽

Ken-ichi Honjoh ◽

Takahisa Miyamoto

Keyword(s):

Antimicrobial Agents ◽

Host Strain ◽

Phage Resistance ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

Gram Positive Bacteria ◽

T7 Phage

We demonstrated that we could combine LLB and phage to construct promising novel antimicrobial agents, LLB-phage. The first LLB-phage, lnqQ -T7 phage, can control the growth of both the Gram-negative host strain and neighboring Gram-positive bacteria while preventing the emergence of phage resistance in the host strain.

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Removal of reactive dyes from aqueous solution by different bacterial genera

Water Science & Technology ◽

10.2166/wst.1996.0243 ◽

1996 ◽

Vol 34 (10) ◽

pp. 89-95 ◽

Cited By ~ 19

Author(s):

Hu Tai-Lee

Keyword(s):

Aqueous Solution ◽

Reactive Dyes ◽

Bacterial Biomass ◽

Gram Negative Bacteria ◽

Adsorption Parameters ◽

Gram Negative ◽

E Coli ◽

Gram Positive Bacteria ◽

Mixed Biomass ◽

Decreasing Ph

The use of biomass for the removal of reactive dyes from an aqueous solution with different bacterial genera has been investigated. Three Gram-negative bacteria: Aeromonas sp., P. luteola and E. coli, and two Gram-positive bacteria: B. subtilis and S. aureus and a mixed biomass of activated sludge are the tested biosorbents. Dead cells of Gram-negative bacteria have a higher specific adsorption capacity than the living cells. The dye removal is in the order of Aeromonoas sp. > P. luteola > E. coli. The adsorption equilibrium can be reached within one hour. Due to the positively charged cells at acidic pH, the removal of reactive dyes increases with decreasing pH. Evaluating the adsorption parameters, bacterial biomass exhibits stable adsorption characteristics, which makes it a suitable adsorbent for different dye compounds.

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P1173PERITONEAL DIALYSIS INFECTIONS IN MALTA - TRENDS OVER ELEVEN YEARS

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfaa142.p1173 ◽

2020 ◽

Vol 35 (Supplement_3) ◽

Author(s):

Angela Borg Cauchi ◽

Maria Angela Gauci ◽

Theresia Dalli ◽

James Gauci ◽

James Farrugia ◽

...

Keyword(s):

Peritoneal Dialysis ◽

Coagulase Negative Staphylococcus ◽

Distributed Data ◽

Dialysis Modality ◽

Gram Positive ◽

Gram Negative ◽

Male Predominance ◽

E Coli ◽

Number Of Patients ◽

Gram Negative Organisms

Abstract Background and Aims Infections related to peritoneal dialysis (PD) are still a cause of morbidity and mortality. We describe an overview of PD peritonitis and catheter-related infections (CRI) in Malta over a period of eleven years. We also describe trends in dialysis modality over the years. Method All patients undergoing PD in Malta during 2008 and 2018 were analysed. Data from 2008-2012 was retrospective, shown as mean, that from 2013-2018 prospective. International Society for Peritoneal Dialysis (ISPD) definitions were used. Results for categorical responses were summarized using absolute numbers and percentages. Medians (range) were used to describe continuous non-normally distributed data. Results The total number of patients undergoing PD from 2008 till 2018 were 137 (2008-2012), 91, 80, 126, 117, 102, 103 respectively. There was an overall male predominance of 63.5% (61-67). Patient years at risk were 85.80, 85.25, 89.71, 83.70, 79.69, 72.88 since 2013 respectively. The overall incidence of diabetes mellitus was 45.3% (41.8-50), cardiovascular disease 34.2% (33.8-35), hypertension 79.3% (73.8-84.6). PD was used in 50% of dialysis modality prior to 2012, 39% in 2018. Initially 51% used Automated PD (APD), with 21% assisted PD, in 2018 39% used APD, with 6% assisted PD. PD peritonitis rates from 2008 were 0.38, 0.31, 0.35, 0.46, 0.43, 0.57, 0.54, 0.43, 0.39, 0.40, 0.46 episodes/patient year respectively There was marked dominance of Gram-positive peritonitis, mainly Staphylococcal, with a reduction of coagulase-negative-Staphylococcus from 0.26 episodes/patient in 2013 to 0.03 in 2017, 0.11 in 2018. Methicillin-resistant S. aureus (MRSA) peritonitis decreased from 0.03 episodes/patient to nil in 2016, 2017, 0.01 episodes/patient in 2018. Amongst Gram-negative peritonitis, Pseudomonas rates decreased from 0.06 to 0.03 episodes/patient in 2018, nil in 2016. Escherichia coli rates decreased from 0.02 episodes/patient to nil in the last three years. Fungal rates from 0.03 to 0.01 episodes/patient/year, with nil in 2016, 2017. Catheter-related infection rates were 0.39 (2008-2012), 0.35, 0.91, 0.37, 0.38, 0.25, 0.50 episodes/patient/year respectively. There was a higher incidence of recurrent infections in 2014, none in 2015 and 2016. Gram-negative organisms accounted for 57% of all CRI, predominantly Pseudomonas at 0.12 (2008-2012), 0.06, 0.09, 0.09, 0.14, 0.03, 017 episodes/patient/year respectively. Gram-positive CRI were mostly Staphylococcus aureus, peaking in 2014 at 0.38 episodes/patient/year. MRSA rates declined from 0.15 to 0.01 episodes/patient/year in 2018. Conclusion PD peritonitis rates in Malta between 2008 and 2018 were below the ISPD recommended threshold. There were no episodes of MRSA in 2016, 2017, no Pseudomonas in 2016, no E coli in the last three years and no fungal PD peritonitis in 2016, 2017. CRI rates also declined, with an overall predominance of Gram-negative infections.

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Fusobacterium nucleatum, the first Gram-negative bacterium demonstrated to produce polyglutamate

Canadian Journal of Microbiology ◽

10.1139/w09-003 ◽

2009 ◽

Vol 55 (5) ◽

pp. 627-632 ◽

Cited By ~ 33

Author(s):

Thomas Candela ◽

Marie Moya ◽

Michel Haustant ◽

Agnès Fouet

Keyword(s):

In Silico Analysis ◽

Fusobacterium Nucleatum ◽

Gram Negative Bacteria ◽

Negative Bacterium ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

The Third ◽

Gram Negative Organisms ◽

First Time

Poly-γ-glutamate has been described in many Gram-positive organisms. When anchored to the surface, it is a capsule and as such a virulence factor. Based on sequence similarities, few Gram-negative organisms have been suggested to synthesize poly-γ-glutamate. For the first time, a Gram-negative bacterium, Fusobacterium nucleatum , is shown to produce and secrete poly-γ-glutamate. Putative poly-γ-glutamate-synthesizing genes from Gram-negative organisms have been compared with their Gram-positive homologs by in silico analysis, i.e., gene sequence and phylogenetic analysis. Clusters of three instead of four genes were highlighted by our screen. The products of the first two genes display similarity with their Gram-positive equivalents, yet the sequences from the Gram-negative organisms can be distinguished from those of the Gram-positives. Interestingly, the sequence of the predicted product of the third gene is conserved among Gram-negative bacteria but displays no similarity to that of either the third or fourth gene of the Gram-positive operons. It is suggested that, like for Gram-positive bacteria, poly-γ-glutamate has a role in virulence for pathogens and one in survival for other Gram-negative bacteria.

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Heterogeneous and Flexible Transmission ofmcr-1in Hospital-AssociatedEscherichia coli

mBio ◽

10.1128/mbio.00943-18 ◽

2018 ◽

Vol 9 (4) ◽

Cited By ~ 23

Author(s):

Yingbo Shen ◽

Zuowei Wu ◽

Yang Wang ◽

Rong Zhang ◽

Hong-Wei Zhou ◽

...

Keyword(s):

Escherichia Coli ◽

Genomic Analysis ◽

Multidrug Resistant ◽

Fluoroquinolone Resistance ◽

Gram Negative Bacteria ◽

Colistin Resistance ◽

Gram Negative ◽

Content Type ◽

E Coli ◽

Genes Encoding

ABSTRACTThe recent emergence of a transferable colistin resistance mechanism, MCR-1, has gained global attention because of its threat to clinical treatment of infections caused by multidrug-resistant Gram-negative bacteria. However, the possible transmission route ofmcr-1amongEnterobacteriaceaespecies in clinical settings is largely unknown. Here, we present a comprehensive genomic analysis ofEscherichia coliisolates collected in a hospital in Hangzhou, China. We found thatmcr-1-carrying isolates from clinical infections and feces of inpatients and healthy volunteers were genetically diverse and were not closely related phylogenetically, suggesting that clonal expansion is not involved in the spread ofmcr-1. Themcr-1gene was found on either chromosomes or plasmids, but in most of theE. coliisolates,mcr-1was carried on plasmids. The genetic context of the plasmids showed considerable diversity as evidenced by the different functional insertion sequence (IS) elements, toxin-antitoxin (TA) systems, heavy metal resistance determinants, and Rep proteins of broad-host-range plasmids. Additionally, the genomic analysis revealed nosocomial transmission ofmcr-1and the coexistence ofmcr-1with other genes encoding β-lactamases and fluoroquinolone resistance in theE. coliisolates. These findings indicate thatmcr-1is heterogeneously disseminated in both commensal and pathogenic strains ofE. coli, suggest the high flexibility of this gene in its association with diverse genetic backgrounds of the hosts, and provide new insights into the genome epidemiology ofmcr-1among hospital-associatedE. colistrains.IMPORTANCEColistin represents one of the very few available drugs for treating infections caused by extensively multidrug-resistant Gram-negative bacteria. The recently emergentmcr-1colistin resistance gene threatens the clinical utility of colistin and has gained global attention. Howmcr-1spreads in hospital settings remains unknown and was investigated by whole-genome sequencing ofmcr-1-carryingEscherichia coliin this study. The findings revealed extraordinary flexibility ofmcr-1in its spread among genetically diverseE. colihosts and plasmids, nosocomial transmission ofmcr-1-carryingE. coli, and the continuous emergence of novel Inc types of plasmids carryingmcr-1and newmcr-1variants. Additionally,mcr-1was found to be frequently associated with other genes encoding β-lactams and fluoroquinolone resistance. These findings provide important information on the transmission and epidemiology ofmcr-1and are of significant public health importance as the information is expected to facilitate the control of this significant antibiotic resistance threat.

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ICU treatment of sepsis and septic shock

10.1093/med/9780199568741.003.0152 ◽

2018 ◽

Author(s):

Matt Wise ◽

Paul Frost

Keyword(s):

Septic Shock ◽

Elderly Population ◽

Indwelling Catheters ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Patient Demographics ◽

Dramatic Rise ◽

Gram Negative Organisms ◽

Sepsis And Septic Shock ◽

Icu Treatment

Bacteria are the most frequent causes of severe sepsis and septic shock, while viruses, fungi, and parasites are implicated less often. Positive cultures are found in only 60% of cases; this may be the result of previous antibiotic therapy or inadequate sampling or testing. The etiology of sepsis is constantly changing; whereas Gram-negative organisms used to make up the majority of cases, Gram-positive bacteria now predominate. Sepsis due to fungal disease has also seen a dramatic rise. These changes may be explained by alterations in patient demographics, such as an increasingly elderly population with multiple comorbidities; an increased frequency of indwelling catheters or devices; and greater numbers of patients with immunosuppression as a result of disease or drug therapy. This chapter covers symptoms, demographics, diagnosis, investigation, prognosis, and treatment within the ITU environment.

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