Nonspecific resistance to bacterial infections. Enhancement by ubiquinone-8.

A lipid fraction from Escherichia coli was extracted with apolar solvents and was found to protect mice from a number of experimental bacterial infections. The benzoquinone, ubiquinone-8, was isolated from this extract by high pressure liquid chromatography and identified as such by nuclear magnetic resonance and mass spectrometry. At a dose of 25 mg/kg this substance was found to provide complete protection against otherwise lethal infections with gram-negative and gram-positive bacteria in mice. Treatment was most effective when given intravenously 24 h before infection. In comparative studies, ubiquinone-8 had a clearly higher activity than ubiquinones-4, Q6, and Q10. A highly significant increase in the clearance rate of bacteria from the blood by the spleen and the liver of treated animals, correlated well with the protective effect of ubiquinone-8. The compound stimulated the ability of mouse macrophages to incorporate sheep erythrocytes and significantly increased the number of antibody-producing cells in spleens of mice.

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Reactions of tin- and triorganotin(IV) isopropoxides with thymol derivative: Synthesis, characterization and in vitro antimicrobial screening

Journal of the Serbian Chemical Society ◽

10.2298/jsc120917030m ◽

2013 ◽

Vol 78 (9) ◽

pp. 1323-1333 ◽

Cited By ~ 8

Author(s):

Garima Matela ◽

Robina Aman ◽

Chetan Sharma ◽

Smita Chaudhary

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Nuclear Magnetic Resonance ◽

Antibacterial Activity ◽

Gram Negative Bacteria ◽

Carboxylate Group ◽

Gram Negative ◽

Gram Positive Bacteria ◽

1H Nuclear Magnetic Resonance

A new series of diisopropyloxytin- and triorganotin(IV) complexes of H2hbgl (1) of the general formula Sn(OPri)2(hbgl) (2), Sn(OPri)2(Hhbgl)2 (3), Ph3Sn(Hhbgl) (4), Bu3Sn(Hhbgl) (5) and Me3Sn(Hhbgl) (6), [where H2hbgl= a ligand of thymol derivative namely, N-(2-hydroxy-3-isopropyl-6-methyl benzyl)Glycine] were synthesized by reacting tin- and triorganotin(IV) chloride with the ligand, with the aid of sodium iso-propoxide in appropriate stiochiometric ratios (1:1 and 1:2). These complexes were characterized by elemental analysis, IR, 1H nuclear magnetic resonance. The spectral data suggest that the carboxylate group, in complexes 2-5, was bonded in a bidentate manner, while a unidentate bonding was observed in complex 6. All five complexes were tested in vitro for their antibacterial activity against Gram-positive bacteria namely, Staphylococcus aureus MTCC 96, Bacillus subtilis MTCC 121 and two Gram-negative bacteria namely, Escherichia coli MTCC 1652 and Pseudomonas aeruginosa MTCC 741. All the five complexes were also tested against three pathogenic fungal strains namely, Aspergillus niger, A. flavus and Penicillium sp.

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Epidemiology of patients with central nervous system infections, mainly neurosurgical patients: a retrospective study from 2012 to 2019 in a teaching hospital in China

BMC Infectious Diseases ◽

10.1186/s12879-021-06561-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Zheng Zhang ◽

Yan Song ◽

Jianbang Kang ◽

Surong Duan ◽

Qi Li ◽

...

Keyword(s):

Risk Factors ◽

Escherichia Coli ◽

Central Nervous System ◽

Nervous System ◽

Retrospective Study ◽

Bacterial Infections ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Cns Infections

Abstract Background Central nervous system (CNS) infections are relatively rare but are associated with high mortality worldwide. Empirical antimicrobial therapy is crucial for the survival of patients with CNS infections, and should be based on the knowledge of the pathogen distribution and antibiotic sensitivities. The aim of this study was to investigate the features of pathogens in patients with CNS infections in North China and evaluate the risk factors for mortality and multi-drug-resistant (MDR) bacterial infections. Methods A retrospective study was conducted with patients with positive cerebrospinal fluid (CSF) cultures in a teaching hospital from January 2012 to December 2019. The following data were collected: demographic characteristics, laboratory data, causative organisms and antimicrobial sensitivity results. Data were analyzed with SPSS 16.0. Univariate analysis and binary logistic regression analyses were performed to identify the risk factors for mortality and MDR bacterial infections. Results A total of 72 patients were diagnosed with CNS infections, and 86 isolates were identified. The proportions of Gram-positive bacteria, Gram-negative bacteria and fungi were 59.3, 30.2 and 10.5%, respectively. The predominant Gram-positive bacteria was Coagulase-negative Staphylococci. Acinetobacter baumannii, Escherichia coli and Klebsiella spp. were the predominant Gram-negative bacteria. Compared to 2012–2015 years, the proportion of Gram-negative bacteria increased markedly during 2016–2019 years. Coagulase-negative Staphylococci, Streptococcus pneumoniae and Enterococcus faecium had 100% sensitivity to vancomycin, teicoplanin and linezolid. Acinetobacter baumannii and Klebsiella pneumoniae were 100% sensitive to tigecycline. Escherichia coli had 100% sensitivity to amikacin, meropenem and imipenem. The overall mortality rate in the 72 patients was 30.6%. In multivariate analysis, age > 50 years, pulmonary infections and CSF glucose level < the normal value were associated with poor outcomes. CSF adenosine deaminase level > the normal value and the presence of external ventricular drainage/lumbar cistern drainage were associated with MDR bacterial infections. Conclusions The mortality rate due to CNS infections reached 30.6% in our study. The proportion of Gram-negative bacteria has increased markedly in recent years. We should give particular attention to patients with risk factors for mortality and MDR bacterial infections mentioned above.

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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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Pyelonephritis in Pediatric Uropathic Patients: Differences from Community-Acquired Ones and Therapeutic Protocol Considerations. A 10-Year Single-Center Retrospective Study

Children ◽

10.3390/children8060436 ◽

2021 ◽

Vol 8 (6) ◽

pp. 436

Author(s):

Giovanni Parente ◽

Tommaso Gargano ◽

Stefania Pavia ◽

Chiara Cordola ◽

Marzia Vastano ◽

...

Keyword(s):

Escherichia Coli ◽

Retrospective Study ◽

Success Rate ◽

Pediatric Population ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Significant Difference ◽

Klebsiella Spp

Pyelonephritis (PN) represents an important cause of morbidity in the pediatric population, especially in uropathic patients. The aim of the study is to demonstrate differences between PNs of uropathic patients and PNs acquired in community in terms of uropathogens involved and antibiotic sensitivity; moreover, to identify a proper empiric therapeutic strategy. A retrospective study was conducted on antibiograms on urine cultures from PNs in vesicoureteral reflux (VUR) patients admitted to pediatric surgery department and from PNs in not VUR patients admitted to Pediatric Emergency Unit between 2010 and 2020. We recorded 58 PNs in 33 patients affected by VUR and 112 PNs in the not VUR group. The mean age of not VUR patients at the PN episode was 1.3 ± 2.6 years (range: 20 days of life–3 years), and almost all the urine cultures, 111 (99.1%), isolated Gram-negative bacteria and rarely, 1 (0.9%), Gram-positive bacteria. The Gram-negative uropathogens isolated were Escherichia coli (97%), Proteus mirabilis (2%), and Klebsiella spp. (1%). The only Gram-positive bacteria isolated was an Enterococcus faecalis. As regards the antibiograms, 96% of not VUR PNs responded to beta-lactams, 99% to aminoglycosides, and 80% to sulfonamides. For the VUR group, mean age was 3.0 years ± 3.0 years (range: 9 days of life–11 years) and mean number of episodes per patient was 2.0 ± 1.0 (range: 1–5); 83% of PNs were by Gram-negatives bacteria vs. 17% by Gram-positive: the most important Gram-negative bacteria were Pseudomonas aeruginosa (44%), Escherichia coli (27%), and Klebsiella spp. (12%), while Enterococcus spp. determined 90% of Gram-positive UTIs. Regimen ampicillin/ceftazidime (success rate: 72.0%) was compared to ampicillin/amikacin (success rate of 83.0%): no statistically significant difference was found (p = 0.09). The pathogens of PNs in uropathic patients are different from those of community-acquired PNs, and clinicians should be aware of their peculiar antibiotic susceptibility. An empiric therapy based on the association ampicillin + ceftazidime is therefore suggested.

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Chemical Composition and Antimicrobial Activity of the Essential Oil from Chaerophyllum Aureum L. (Apiaceae)

Natural Product Communications ◽

10.1177/1934578x0900400125 ◽

2009 ◽

Vol 4 (1) ◽

pp. 1934578X0900400 ◽

Cited By ~ 2

Author(s):

Branislava Lakušić ◽

Violeta Slavkovska ◽

Milica Pavlović ◽

Marina Milenković ◽

Jelena Antić Stanković ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Candida Albicans ◽

Chemical Composition ◽

Micrococcus Luteus ◽

Bacterial Strains ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Aerial Parts

The essential oils of the aerial parts and fruits of Chaerophyllum aureum L., collected from two mountains in Serbia, were analyzed by GC and GC/MS. Sabinene (18.5-31.6%), p-cymene (7.9-25.4%) and limonene (1.9-10.9%) were characterized as the main constituents. The oils were tested against six bacterial strains and one strain of yeast, Candida albicans. The highest antimicrobial activity was observed against the Gram-positive bacteria Staphylococcus aureus, S. epidermidis and Micrococcus luteus, while of the Gram-negative strains, Escherichia coli was the most sensitive.

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Survival of some non-starter bacteria in naturally ripened and enzyme-accelerated Cheddar cheese

Journal of Dairy Research ◽

10.1017/s0022029900033380 ◽

1988 ◽

Vol 55 (4) ◽

pp. 597-602 ◽

Cited By ~ 5

Author(s):

Lydia Bautista ◽

Rohan G. Kroll

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Enterococcus Faecalis ◽

Enzyme System ◽

Cheddar Cheese ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Ripening Period ◽

Gram Positive Bacteria

SummaryEffects of the addition of a proteinase (Neutrase 1–5S) and a peptidase (aminopeptidase DP-102) as agents for accelerating the ripening of Cheddar cheese on the survival of some non-starter bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coliand aSalmonellasp.) were studied throughout a 4-month ripening period. The enzymes were found to have no significant effect on the survival of the Gram-positive bacteria but some significant effects were observed, at some stages of the ripening period, with the Gram-negative bacteria in that lower levels were recovered from cheeses treated with the enzyme system.

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Different Modes of Action of Naphthyridones in Gram-Positive and Gram-Negative Bacteria

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.50.1.385-387.2006 ◽

2006 ◽

Vol 50 (1) ◽

pp. 385-387 ◽

Cited By ~ 16

Author(s):

Ed T. Buurman ◽

Kenneth D. Johnson ◽

Roxanne K. Kelly ◽

Kathy MacCormack

Keyword(s):

Escherichia Coli ◽

Haemophilus Influenzae ◽

Mode Of Action ◽

Bacterial Pathogens ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Modes Of Action

ABSTRACT Naphthyridones that were recently described as a class of translation inhibitors in gram-positive bacteria mediate their mode of action via GyrA in Haemophilus influenzae and Escherichia coli. These are the first examples of compounds in which modes of action in different bacterial pathogens are mediated through widely different targets.

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Synthesis of cyclotetrapeptide analogues of c-PLAI and evaluation of their antimicrobial properties

Royal Society Open Science ◽

10.1098/rsos.201822 ◽

2021 ◽

Vol 8 (3) ◽

Author(s):

Rani Maharani ◽

Orin Inggriani Napitupulu ◽

Jelang M. Dirgantara ◽

Ace Tatang Hidayat ◽

Dadan Sumiarsa ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Properties ◽

Trichophyton Mentagrophytes ◽

Solution Phase ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Aromatic Residues ◽

Gram Positive Bacteria ◽

Lysine Residues ◽

Bacteria And Fungi

Antimicrobial peptides (AMPs) are interesting compounds owing to their ability to kill several pathogens. In order to identify new AMPs, c-PLAI analogues were synthesized and evaluated together with their linear precursors for their antimicrobial properties against two Gram-positive bacteria ( Staphylococcus aureus and Bacillus cereus ), two Gram-negative bacteria ( Escherichia coli and Klebsiella pneumoniae ), and two fungal strains ( Candida albicans and Trichophyton mentagrophytes ). The new c-PLAI analogues were prepared through a combination of solid- and solution-phase syntheses, as previously employed for the synthesis of c-PLAI. The antimicrobial activity tests showed that the synthetic parent peptide c-PLAI was inactive or weakly active towards the bioindicators employed in the assay. The tests also indicated that cyclic c-PLAI analogues possessed enhanced antimicrobial properties against most of the bacteria and fungi tested. Furthermore, this study revealed that analogues containing cationic lysine residues displayed the highest activity towards most bioindicators. A combination of lysine and aromatic residues yielded analogues with broad-spectrum antimicrobial properties.

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First results of complex studies of modern microorganisms by physico-chemical and mineral-geochemical methods

Vestnik of Geosciences ◽

10.19110/geov.2021.9.1 ◽

2021 ◽

Vol 9 ◽

pp. 3-33

Author(s):

V. I. Silaev ◽

◽

A. V. Kokin ◽

N. V. Pavlovich ◽

S. N. Shanina ◽

...

Keyword(s):

Mass Spectrometry ◽

Amino Acids ◽

Amino Acid ◽

Chemical Composition ◽

Amino Acid Content ◽

Total Amino Acid ◽

Strong Positive Correlation ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria

We studied 14 samples of gram-negative and gram-positive bacteria, unicellular yeasts and green algae using optical, atomic force and analytical scanning electron microscopy, thermal analysis, gas chromatography, infrared spectroscopy, inductively coupled plasma mass spectrometry and isotope mass spectrometry. In shape, the cells of microorganisms vary from rod-shaped to lenticular and coccoid, in size they range from mesonanometer to micrometer. A strong positive correlation was found between the extreme cell sizes. An admixture of inorganic chemical elements — Mg, Ca, Ba, Na, K, Cu, Zn, P, S, Cl and submicron-sized precipitates of mineral phases — carbonates, phosphate sulfates, hydrogen sulfate phosphates, hydrogen phosphates, halite, kaolinite, was found in the chemical composition of the studied microorganisms, metal alloys of brass composition, baddeleyite. Among the 45 microelements identified in microorganisms, there were 7 essential elements (E), 17 physiogenically active (FA) and 19 abiotic (AB). The total concentration of trace elements ranged from 0.003—0.26 wt. %. The value of the essential coefficient — E / AB — averaged 196 ± 153. Microorganisms were characterized by a mixed fat-protein elemental composition, they contained 14 amino acids belonging to the aliphatic, aromatic, basic, acidic, hydroxyl, imino and sulfur-containing groups. The total amino acid content ranged from 409 to 942 (682 ± 221) mg/g. Up to half of the amino acids were represented by the left (L) and right (D) enantiomers. The degree of racemization (D / L) ranged from 0.01 to 0.37. Yeast and chlorella were characterized by the most isotopically heavy composition of carbon in combination with relatively isotopically light nitrogen. In bacteria, a statistically lighter carbon was found in combination with a much heavier nitrogen. According to a number of properties — the chemical composition of organic matter, microelements, the degree of enrichment with antibiotic elements, the content of amino acids and the degree of their racemization — gram-negative and gram-positive bacteria differed. In general, the studied biological microorganisms were fundamentally different from the abiogenic organic substances found in meteorites and products of modern volcanism regarding their elemental and amino acid composition, carbon and nitrogen isotopes.

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Synthesis, Characterization and Antimicrobial Activities of Co (III) and Fe (III) Complexes of Imino-N-heterocyclic Carbenes Ligands

Chemical Science International Journal ◽

10.9734/csji/2021/v30i630238 ◽

2021 ◽

pp. 59-67

Author(s):

Samaila Abubakar ◽

Musa Muktari ◽

Rejoice Atiko

Keyword(s):

Escherichia Coli ◽

Salmonella Typhi ◽

Antimicrobial Activities ◽

Heterocyclic Carbenes ◽

Gram Negative Bacteria ◽

Disc Diffusion ◽

Gram Negative ◽

E Coli ◽

Gram Positive Bacteria

The synthesis and antimicrobial application of Co (III) and Fe (III) complexes of imine functionalized N-heterocyclic carbene (Imino-NHC) ligands is reported. The ligand precursors 1-(2-[(hydroxyl-benzylidene)-amino]-ethyl)-3-R-3H-imidazol-1-ium bromide where R = pyridyl (1a) and benzyl (1b) have been reported in our previous work. The in-situ generated ligands of 1a and 1b have been successfully coordinated to CoBr2 and [FeI(Cp)(CO)2] leading to the isolation of air-stable N^C^N^O four coordinate Co(III) complex 2 and a six-coordinate Fe(III) complex 3. The synthesised complexes were both found to be NMR inactive hence were characterize using FTIR and LRMS. The complexes were screened for antimicrobial activities against four gram-negative bacteria Escherichia Coli (E-coli), Shigella, Klebsiella pneumoniae (K. Pneumoniae) and Salmonella typhi (S. typhi) and a gram positive bacteria Staphylocossus aureus (S. aureus). The antimicrobial test was conducted using disc diffusion methods and based on the concentrations of 100, 200, 300, 400 and 500 µg/ mL, significant activities were recorded for both cobalt and the iron complexes.

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