Biofilm inhibitory efficiency of phytol in combination with cefotaxime against nosocomial pathogen Acinetobacter baumannii

Acinetobacter baumannii has emerged as a dangerous nosocomial pathogen, particularly for severely ill patients in intensive care units and patients with hematologic malignancies. Here, we present the complete genome sequence of a multidrug-resistant A. baumannii isolate, recovered from a Mexican hospital and classified as sequence type 422 according to the multilocus sequence typing Pasteur scheme.

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Serum Albumin and Ca2+Are Natural Competence Inducers in the Human Pathogen Acinetobacter baumannii

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00529-16 ◽

2016 ◽

Vol 60 (8) ◽

pp. 4920-4929 ◽

Cited By ~ 23

Author(s):

German Matias Traglia ◽

Brettni Quinn ◽

Sareda T. J. Schramm ◽

Alfonso Soler-Bistue ◽

Maria Soledad Ramirez

Keyword(s):

Acinetobacter Baumannii ◽

Natural Transformation ◽

Hospital Environment ◽

Human Pathogen ◽

Nosocomial Pathogen ◽

Natural Competence ◽

Exogenous Dna ◽

Content Type ◽

Resistance Determinants ◽

Main Protein

ABSTRACTThe increasing frequency of bacteria showing antimicrobial resistance (AMR) raises the menace of entering into a postantibiotic era. Horizontal gene transfer (HGT) is one of the prime reasons for AMR acquisition.Acinetobacter baumanniiis a nosocomial pathogen with outstanding abilities to survive in the hospital environment and to acquire resistance determinants. Its capacity to incorporate exogenous DNA is a major source of AMR genes; however, few studies have addressed this subject. The transformation machinery as well as the factors that induce natural competence inA. baumanniiare unknown. In this study, we demonstrate that naturally competent strain A118 increases its natural transformation frequency upon the addition of Ca2+or albumin. We show thatcomEAandpilQare involved in this process since their expression levels are increased upon the addition of these compounds. An unspecific protein, like casein, does not reproduce this effect, showing that albumin's effect is specific. Our work describes the first specific inducers of natural competence inA. baumannii. Overall, our results suggest that the main protein in blood enhances HGT inA. baumannii, contributing to the increase of AMR in this threatening human pathogen.

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Low concentrations of commercial alcohol hand rubs facilitate growth of and secretion of extracellular proteins by multidrug-resistant strains of Acinetobacter baumannii

Journal of Medical Microbiology ◽

10.1099/jmm.0.47442-0 ◽

2007 ◽

Vol 56 (12) ◽

pp. 1595-1599 ◽

Cited By ~ 20

Author(s):

Justin Edwards ◽

Geeta Patel ◽

David W. Wareham

Keyword(s):

Acinetobacter Baumannii ◽

Culture Supernatant ◽

Multidrug Resistant ◽

Extracellular Proteins ◽

Nosocomial Pathogen ◽

Emulsifying Activity ◽

Health Care Settings ◽

Low Concentrations ◽

Resistant Strains ◽

Minimal Media

Acinetobacter baumannii is increasingly recognized as an important multidrug-resistant nosocomial pathogen. Recent work has highlighted enhanced growth and heightened virulence in the presence of ethyl alcohols. As alcohol-based hand rubs (ABHRs) are extensively used in health care settings, the authors set out to determine whether the hand rubs could also influence the growth of prevalent multidrug-resistant strains circulating in UK hospitals. A significant increase in growth was observed when minimal media were supplemented with concentrations of 1 % and lower of four commercially available hand rubs. In addition, growth in ABHR-supplemented media resulted in secretion of proteins into the culture supernatant. One of these was identified as OmpA, which is recognized as having emulsifying activity, which could potentially confer enhanced pathogenicity to A. baumannii.

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Functional Characterization of AbaQ, a Novel Efflux Pump Mediating Quinolone Resistance inAcinetobacter baumannii

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00906-18 ◽

2018 ◽

Vol 62 (9) ◽

Cited By ~ 8

Author(s):

María Pérez-Varela ◽

Jordi Corral ◽

Jesús Aranda ◽

Jordi Barbé

Keyword(s):

Acinetobacter Baumannii ◽

Antimicrobial Agents ◽

Efflux Pump ◽

Functional Characterization ◽

Multidrug Resistant ◽

Quinolone Resistance ◽

Nosocomial Pathogen ◽

Content Type ◽

Mfs Transporter

ABSTRACTAcinetobacter baumanniihas emerged as an important multidrug-resistant nosocomial pathogen. In previous work, we identified a putative MFS transporter, AU097_RS17040, involved in the pathogenicity ofA. baumannii(M. Pérez-Varela, J. Corral, J. A. Vallejo, S. Rumbo-Feal, G. Bou, J. Aranda, and J. Barbé, Infect Immun 85:e00327-17, 2017,https://doi.org/10.1128/IAI.00327-17). In this study, we analyzed the susceptibility to diverse antimicrobial agents ofA. baumanniicells defective in this transporter, referred to as AbaQ. Our results showed that AbaQ is mainly involved in the extrusion of quinolone-type drugs inA. baumannii.

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Widespread dispersion of the resistance element tet(B)::ISCR2 in XDR Acinetobacter baumannii isolates

Epidemiology and Infection ◽

10.1017/s0950268815002897 ◽

2015 ◽

Vol 144 (7) ◽

pp. 1574-1578 ◽

Cited By ~ 6

Author(s):

E. VILACOBA ◽

M. ALMUZARA ◽

L. GULONE ◽

G. M. TRAGLIA ◽

S. MONTAÑA ◽

...

Keyword(s):

Drug Resistance ◽

Acinetobacter Baumannii ◽

Tetracycline Resistance ◽

Drug Resistant ◽

Nosocomial Pathogen ◽

Pcr Assay ◽

Extreme Drug Resistance ◽

Different Levels

SUMMARYAcinetobacter baumannii is a significant nosocomial pathogen often associated with extreme drug resistance (XDR). In Argentina, isolates of A. baumannii resistant to tetracyclines have accounted for more than 40% of drug-resistant isolates in some hospitals. We have previously reported the dispersion of the tet(B) resistance element associated with the ISCR2 transposase in epidemiologically unrelated A. baumannii isolates recovered from 1983 to 2011. This study extends this surveillance to 77 recent (2009–2013) XDR A. baumannii isolates with different levels of minocycline susceptibility. Isolates were examined by a pan-PCR assay, which showed six different amplification patterns, and specific PCRs were used for the confirmation of the the ΔISCR2-tet(B)-tet(R)-ISCR2 element. The tet(B) gene was present in 66 isolates and the ISCR2 element in 68 isolates; the tet(B) gene was associated with ISCR2 in all tet(B)-positive isolates. We conclude that this element is widespread in XDR A. baumannii isolates from Argentina and could be responsible for the emergence of tetracycline resistance in recent years.

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Multiple Quorum Quenching Enzymes Are Active in the Nosocomial Pathogen Acinetobacter baumannii ATCC17978

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2018.00310 ◽

2018 ◽

Vol 8 ◽

Cited By ~ 19

Author(s):

Celia Mayer ◽

Andrea Muras ◽

Manuel Romero ◽

María López ◽

María Tomás ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Quorum Quenching ◽

Nosocomial Pathogen

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Complete Genome Sequence of the Nosocomial Pathogen Acinetobacter nosocomialis Strain M2

Microbiology Resource Announcements ◽

10.1128/mra.00538-19 ◽

2019 ◽

Vol 8 (44) ◽

Author(s):

Bailey Pehde ◽

Nicholas Lizer ◽

Michael Carruthers

Keyword(s):

Acinetobacter Baumannii ◽

Genome Sequence ◽

Complete Genome Sequence ◽

Complete Genome ◽

Acinetobacter Calcoaceticus ◽

Human Pathogen ◽

Nosocomial Pathogen ◽

Content Type ◽

Opportunistic Human Pathogen

Acinetobacter nosocomialis is an opportunistic human pathogen that is part of the Acinetobacter calcoaceticus/Acinetobacter baumannii (ACB) complex. Here, we report the complete genome sequence of Acinetobacter nosocomialis strain M2.

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Biocide susceptibilities and biofilm-forming capacities of Acinetobacter baumannii clinical isolates from Malaysia

The Journal of Infection in Developing Countries ◽

10.3855/jidc.11455 ◽

2019 ◽

Vol 13 (07) ◽

pp. 626-633

Author(s):

Muhammad Harith Nor A'shimi ◽

Ahmed Ghazi Alattraqchi ◽

Farahiyah Mohd Rani ◽

Nor Iza A Rahman ◽

Salwani Ismail ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Benzalkonium Chloride ◽

Inhibitory Concentration ◽

Antimicrobial Compounds ◽

Nosocomial Pathogen ◽

Chain Reaction ◽

Gram Negative ◽

Biocide Resistance ◽

Benzethonium Chloride ◽

Polymerase Chain

Introduction. Acinetobacter baumannii is a Gram-negative nosocomial pathogen that has the capacity to develop resistance to all classes of antimicrobial compounds. However, very little is known regarding its susceptibility to biocides (antiseptics and disinfectants) and capacity to form biofilms, particularly for Malaysian isolates. Aim. To determine the susceptibility of A. baumannii isolates to commonly-used biocides, investigate their biofilm-forming capacities and the prevalence of biocide resistance and biofilm-associated genes. Methodology. The minimum inhibitory concentration (MIC) values of 100 A. baumannii hospital isolates from Terengganu, Malaysia, towards the biocides benzalkonium chloride (BZK), benzethonium chloride (BZT) and chlorhexidine digluconate (CLX), were determined by broth microdilution. The isolates were also examined for their ability to form biofilms in 96-well microplates. The prevalence of biocide resistance genes qacA, qacE and qacDE1 and the biofilm-associated genes bap and abaI were determined by polymerase chain reaction (PCR). Results. Majority of the A. baumannii isolates (43%) showed higher MIC values (> 50 µg/mL) for CLX than for BZK (5% for MIC > 50 µg/mL) and BZT (9% for MIC > 50 µg/mL). The qacDE1 gene was predominant (63%) followed by qacE (28%) whereas no isolate was found harbouring qacA. All isolates were positive for the bap and abaI genes although the biofilm-forming capacity varied among the isolates. Conclusion. The Terengganu A. baumannii isolates showed higher prevalence of qacDE1 compared to qacE although no correlation was found with the biocides’ MIC values. No correlation was also observed between the isolates’ biofilm-forming capacity and the MIC values for the biocides.

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