Antimicrobial Potential of Natural and Semi-Synthetic ent-Kaurane and ent-Pimarane Diterpenes against Clinically Isolated Gram-Positive Multidrug-Resistant Bacteria

The aim of the study was to assess the epidemiology, the incidence of multidrug-resistant bacteria and bloodstream infections’ (BSIs) seasonality in a university hospital. This retrospective study was carried out in the University General Hospital of Patras, Greece, during 2011–13 y. Blood cultures from patients with clinical presentation suggestive of bloodstream infection were performed by the BacT/ALERT System. Isolates were identified by Vitek 2 Advanced Expert System. Antibiotic susceptibility testing was performed by the disk diffusion method and E-test. Resistance genes (mecA in staphylococci; vanA/vanB/vanC in enterococci; blaKPC/blaVIM/blaNDM in Klebsiella spp.) were detected by PCR. In total, 4607 (9.7%) blood cultures were positive from 47451 sets sent to Department of Microbiology, representing 1732 BSIs. Gram-negative bacteria (52.3%) were the most commonly isolated, followed by Gram-positive (39.5%), fungi (6.6%) and anaerobes bacteria (1.8%). The highest contamination rate was observed among Gram-positive bacteria (42.3%). Among 330 CNS and 150 Staphylococcus aureus, 281 (85.2%) and 60 (40.0%) were mecA-positive, respectively. From 113 enterococci, eight were vanA, two vanB and two vanC-positives. Of the total 207 carbapenem-resistant Klebsiella pneumoniae (73.4%), 202 carried blaKPC, four blaKPC and blaVIM and one blaVIM. A significant increase in monthly BSIs’ incidence was shown (R2: 0.449), which may be attributed to a rise of Gram-positive BSIs (R2: 0.337). Gram-positive BSIs were less frequent in spring (P < 0.001), summer (P < 0.001), and autumn (P < 0.001), as compared to winter months, while Gram-negative bacteria (P < 0.001) and fungi (P < 0.001) were more frequent in summer months. BSIs due to methicillin resistant S. aureus and carbapenem-resistant Gram-negative bacteria increased during the study period. The increasing incidence of BSIs can be attributed to an increase of Gram-positive BSI incidence, even though Gram-negative bacteria remained the predominant ones. Seasonality may play a role in the predominance of Gram-negative’s BSI.

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Genome Sequences of Three Spore-Forming Bacteria Isolated from the Feces of Organically Raised Chickens

Genome Announcements ◽

10.1128/genomea.00880-16 ◽

2016 ◽

Vol 4 (5) ◽

Cited By ~ 2

Author(s):

Victoria Kennedy ◽

Tricia A. Van Laar ◽

Omoshola Aleru ◽

Michael Thomas ◽

Michelle Ganci ◽

...

Keyword(s):

Multidrug Resistant ◽

Resistant Bacteria ◽

Genome Sequences ◽

Multidrug Resistant Bacteria ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Feed Supplements ◽

Chicken Feces ◽

Spore Forming Bacteria

Antibiotic feed supplements have been implicated in the rise of multidrug-resistant bacteria. An alternative to antibiotics is probiotics. Here, we report the genome sequences of two Bacillus and one Solibacillus species, all spore-forming, Gram-positive bacteria, isolated from the feces organically raised chicken feces, with potential to serve as probiotics.

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The Potential of Bacteriophage Lysins in the Treatment of Gram- Positive Bacteria Including Multidrug Resistant Bacteria

Frontiers in Clinical Drug Research: Anti-Infectives ◽

10.2174/9781608058549114010010 ◽

2014 ◽

pp. 308-337

Keyword(s):

Multidrug Resistant ◽

Resistant Bacteria ◽

Multidrug Resistant Bacteria ◽

Gram Positive ◽

Gram Positive Bacteria

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Pimarane-type Diterpenes Obtained by Biotransformation: Antimicrobial Properties Against Clinically Isolated Gram-positive Multidrug-resistant Bacteria

Phytotherapy Research ◽

10.1002/ptr.4887 ◽

2012 ◽

pp. n/a-n/a ◽

Cited By ~ 4

Author(s):

Thiago S. Porto ◽

Marília R. Simão ◽

Lucas Z. Carlos ◽

Carlos H. G. Martins ◽

Niege A. J. C. Furtado ◽

...

Keyword(s):

Antimicrobial Properties ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Multidrug Resistant Bacteria ◽

Gram Positive

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Inhibition of Multidrug-Resistant Gram-Positive and Gram-Negative Bacteria by a Photoactivated Porphyrin

Polish Journal of Microbiology ◽

10.5604/01.3001.0010.7092 ◽

2017 ◽

Vol 66 (4) ◽

pp. 533-536 ◽

Cited By ~ 2

Author(s):

Moreno Bondi ◽

Anna Mazzini ◽

Simona de Niederhäusern ◽

Ramona Iseppi ◽

Patrizia Messi

Keyword(s):

Multidrug Resistant ◽

Resistant Bacteria ◽

Gram Negative Bacteria ◽

Multidrug Resistant Bacteria ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

In Vitro Antibacterial Activity

The authors studied the in vitro antibacterial activity of the photo-activated porphyrin meso-tri(N-methyl-pyridyl), mono(N-tetradecyl-pyridyl)porphine (C14) against four multidrug-resistant bacteria: Staphylococcus aureus, Enterococcus faecalis (Gram-positive), Escherichia coli, Pseudomonas aeruginosa (Gram-negative). Using 10 μg/ml of porphyrin and 60 sec irradiation we observed the remarkable susceptibility of S. aureus and E. faecalis to treatment while, under the same conditions, E. coli and P. aeruginosa showed very low susceptibility. In a later stage, suspensions of Gram-negative bacteria were processed with EDTA before photo-activation, obtaining a significant decrease in viable counts. In view of the results, if the combination of low porphyrin concentrations and short irradiation times will be effective in vivo also, this approach could be a possible alternative to antibiotics, in particular against localized infections due to multidrug-resistant microorganisms.

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Bacteriological Profile of Tracheal Aspirates of the Patients Attending Neuro-hospital Nepal

International Journal of Life Sciences ◽

10.3126/ijls.v4i0.3496 ◽

2010 ◽

Vol 4 ◽

Cited By ~ 3

Author(s):

Pratirodh Koirala ◽

Dwij Raj Bhatta ◽

Prakash Ghimire ◽

Bharat Mani Pokhrel ◽

Upendra Devkota

Keyword(s):

Pseudomonas Aeruginosa ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Gram Negative Bacteria ◽

Viridans Streptococci ◽

Multidrug Resistant Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Tracheal Aspirates

The tracheostomized patients are colonized mostly by gram negative bacteria which lead to either tracheobronchitis or bronchopneumonia. This study was conducted to isolate and identify the potential pathogen causing post tracheostomy infection. A cross-sectional study was conducted during April 2008 to February 2009 based at Neuro Center, Kathmandu. Tracheal aspirates of 50 patients having fever more than 38°C were collected and analyzed for bacterial content. Out of the 50 cases, 45(90%) cases showed bacterial growth. Sixty-seven isolates were identified; with 20(44.4%) poly-microbial cases. Pseudomonas aeruginosa and enteric gram negative bacteria were predominant bacteria (n=27, 40.3%) followed by Staphylococcus aureus (n=7, 10.4%), other Gram negative bacteria (n=4, 5.9%) and Viridans Streptococci (n=2, 2.9%). Pseudomonas aeruginosa were most sensitive to the Amikacin (n=22, 81.4%) and Ciprofloxacin (n=19, 70.3%). All Pseudomonal isolates were resistant to the Cefotaxime. Enteric Gram Negative bacteria (EGNB) were most sensitive to Amikacin and Chloramphenicol (20, 74.0%) and all were resistant to Ampicillin and Cephalexin. All the gram positive bacteria isolated were sensitive to Vancomycin. Among the total isolates, 24 (88.8%) of Pseudomonas aeruginosa, 21 (66.6%) of enteric gram negative bacteria, and 5 (55.5%) of Gram positive bacteria were multidrug resistant (MDR). The study reported alarming condition of MDR in tracheal aspirates. So surveillance for source of multidrug resistant bacteria would be beneficial for intervention of infection related to it. Key words: Tracheal aspirates, polymicrobial growth, Multidrug resistant bacteria (MDR)10.3126/ijls.v4i0.3496International Journal of Life Sciences Vol.4 2010 pp.60-65

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The antimicrobial potential of algicolous marine fungi for counteracting multidrug-resistant bacteria: phylogenetic diversity and chemical profiling

Research in Microbiology ◽

10.1016/j.resmic.2016.04.009 ◽

2016 ◽

Vol 167 (6) ◽

pp. 492-500 ◽

Cited By ~ 8

Author(s):

Giorgio Gnavi ◽

Fortunato Palma Esposito ◽

Carmen Festa ◽

Anna Poli ◽

Pietro Tedesco ◽

...

Keyword(s):

Phylogenetic Diversity ◽

Marine Fungi ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Multidrug Resistant Bacteria ◽

Chemical Profiling ◽

Antimicrobial Potential

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Structure of the enterococcal T4SS protein PrgL reveals unique dimerization interface in the VirB8 protein family

10.1101/2020.10.30.342212 ◽

2020 ◽

Author(s):

Franziska Jäger ◽

Anaïs Lamy ◽

Nina Guerini ◽

Wei-Sheng Sun ◽

Ronnie P-A Berntsson

Keyword(s):

Antibiotic Resistance Genes ◽

Building Blocks ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Secretion Systems ◽

Multidrug Resistant Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Dimerization Interface

AbstractMultidrug resistant bacteria are one of the most important current threats to public health and a serious problem in hospital acquired infections (HAIs). Most antibiotic resistance genes are acquired via conjugative gene transfer, in a process that is mediated by a protein machinery called the Type 4 Secretion System (T4SS). The core of the T4SS is a multiprotein complex that spans both the cell wall and cellular membrane(s), serving as a channel for macromolecular secretion. Although the majority of multidrug resistant bacteria responsible for HAIs are of Gram-positive origin, with Enterococci being major contributors, mostly Gram-negative T4SSs have been characterized. Here we describe the structure and organisation of PrgL, one of the seven membrane proteins forming the translocation channel of the T4SS encoded by the pCF10 plasmid from Enterococcus faecalis. We present the structure of the C-terminal domain of PrgL, which displays similarity to VirB8 proteins of Gram-negative secretion systems. PrgL forms dimers and higher order oligomers but does not interact strongly with the other T4SS components. In vitro experiments show that the soluble domain alone is enough to drive both dimerization and dodecamerisation, with a dimerization interface that differs from all other known VirB8-like proteins. Our findings provide insight into the molecular building blocks of Gram-positive T4SS, highlighting similarities but also unique features in PrgL compared to other VirB8-like proteins.

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