Acinetobacter

PURPOSES: The aim of this study was to determine the frequency of biocide resistant genes, qacA, qacE and cepA in multidrug resistant (MDR) bacteria: Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii and to correlate the presence or absence of resistant genes with biocides susceptibility. MATERIALS AND METHODS: The study included 44 MDR K. pneumoniae, P. aeruginosa and A. baumannii microorganisms. The bacteria were screened for the presence of biocide resistant genes by the polymerase chain reaction (PCR) method...

BACKGROUND: Head lice, Pediculus humanus capitis, are obligate blood-sucking parasites. Phylogenetically, they occur in five divergent mitochondrial clades (A, D, B, C and E), each having a particular geographical distribution. Recent studies have revealed that head lice, as is the case of body lice, can act as a vector for louse-borne diseases. Here, we aimed to study the genetic diversity of head lice collected from Niger's refugees (migrant population) arriving in Algeria, northern Africa, and to look for louse-borne pathogens...

OBJECTIVE: The objective of this study was to evaluate the ability of the BioFire FilmArray Blood Culture Identification (BCID) Panel to rapidly detect pathogens producing late-onset ventilator-associated pneumonia (VAP), a severe infection often produced by Gram negative bacteria. These microorganisms are frequently multidrug resistant (MDR) and typically require broad spectrum empiric treatment. METHODS: In this study, in the context of an international multicenter clinical trial (Magic Bullet), respiratory samples were collected at the time of suspicion of VAP from 165 patients in 32 participating hospitals in Spain, Greece and Italy...

OBJECTIVES: Tigecycline non-susceptible Acinetobacter nosocomialis (TNAN) have been discovered in clinical isolates. The resistance-nodulation-cell division (RND)-type efflux system plays a major role in tigecycline non-susceptible of Acinetobacter baumannii, but the mechanism in Acinetobacter nosocomialis remains unknown. Our aim was to analyze the contribution of efflux based tigecycline resistance in clinical A. nosocomialis isolates collected from multiple medical centers in Taiwan...

Mounting evidence indicates that microbiome plays an important role in the development and progression of cancer. The dogma that urine in healthy individuals must be sterile has been overturned. Dysbiosis of the urinary microbiome has been revealed responsible for various urological disorders, including prostate cancer. The link between chronic inflammation, microbiome and solid tumors has been established for various neoplastic diseases. However, a detailed and comprehensive analysis of urinary microenvironment of bladder cancer has not been yet reported...

Acinetobacter baumannii is a nonfermenting Gram-negative bacillus. A. baumannii resistance is a significant obstacle to clinical infection treatment. The existence of persister cells (persisters) might represent the reason for therapy failure and relapse, and such cells may be the driving force behind rising resistance rates. In this study, A. baumannii ATCC 19606 was used as a target to explore the essential features of A. baumannii persisters. Antibiotic treatment of A. baumannii cultures at 50-fold the minimum inhibitory concentration resulted in a distinct plateau of surviving drug-tolerant persisters...

The emergence of drug-resistant Acinetobacter baumannii is the global health problem associated with high mortality and morbidity. Therefore it is high time to find a suitable therapeutics for this pathogen. In the present study, subtractive proteomics along with reverse vaccinology approaches were used to predict suitable therapeutics against A. baumannii. Using subtractive proteomics, we have identified promiscuous antigenic membrane proteins that contain the virulence factors, resistance factors and essentiality factor for this pathogenic bacteria...

The authors devised a comparative prospective study to determine the in vitro microbicidal efficacy of skin preparation solutions in the concentrations and temperatures used in the burns theatre against common bacterial and fungal microorganisms. A panel of 10 microorganisms Staphylococcus aureus, streptococcus pyogenes, enterococcus faecalis, escherichia coli, pseudomonas aeruginosa, candida albicans, bacillus cereus were assembled comprising 8 common strains of S. aureus (including methicillin resistant staphylococcus aureus (MRSA)), S...

BACKGROUND: Due to the diverse nature of bloodstream infections etiology and to the antibiotic resistance patterns in periodic intervals, rational and accurate use of antibiotics requires an understanding of common causative agents of septicemia and their susceptibility patterns. The present study aimed to determine the bacterial etiology of the neonate and pediatric septicemia, and their antibiotic resistance pattern in Tehran, North of Iran. MATERIAL AND METHODS: This retrospective cross-sectional study was conducted along two years, from October 2014 to November 2016 among children with suspected bloodstream infection...

INTRODUCTION: The emergence of Metallo-beta-lactamase (MBL)-producing Acinetobacter baumannii has become a global concern in nosocomial infections. The aim of this study is to determine the prevalence of MBL producing genes among clinical isolates of A. baumannii from hospitalized patients. METHODS: This study was performed from October 2015 to October 2016 at three teaching hospitals located in Isfahan, Iran. Totally, 100 A-baumannii isolates were collected from clinical specimens and identified as A-baumannii using standard microbiological methods...

Biosynthesis of nanoparticles by fermented plants using microbes is an eco-friendly and cost-effective process. In this study, we used the fungus Aspergillus orayzae for the fermentation process. The aqueous extract of fermented Lupin (AEFL) possesses the ability to reduce selenium ion in the presence of gamma rays evidenced by the color changes to red. Elemental composition, surface morphology, and identity of selenium nanoparticles (SeNPs) were verified by UV-Vis., TEM, DLS, XRD, EDX, SEM and FT-IR. Antimicrobial activity of SeNPs was tested towards multidrug-resistant (MDR) bacteria, and some pathogenic fungi...

Acinetobacter baumannii is a Gram negative organism that is a cause of hospital acquired multidrug resistant (MDR) infections. A. baumannii has a unique cell surface compared to many other Gram-negative pathogens in that it can live without LPS and it has a high content of cardiolipin in the outer membrane. Therefore, to better understand the cell envelope and mechanisms of A. baumannii MDR, we screened a transposon library for mutants with defective permeability barrier function, as defined as a deficiency in the ability to exclude the phosphatase chromogenic substrate, 5-Bromo-4-chloro-3-indolyl phosphate (XP)...

This study was conducted to investigate the prevalence and risk factors for carbapenem-resistant Gram-negative Bacteria (CR-GNB) colonization and acquisition among patients admitted to Intensive Care Units (ICUs) in two tertiary care hospitals in Northern Thailand. Rectal swab screening for CR-GNB was performed on patients at ICU admission and discharge. Phenotypes and genotypes of all isolates were determined. Risk factors were analyzed by logistic regression analysis. Overall, carriage rates of CR-GNB at admission was 11...

Transcriptional analyses of A. baumannii ATCC 17978 showed that the expression of A1S_2091 was enhanced in cells cultured in darkness at 24°C through a process that depended on the BlsA photoreceptor. Disruption of A1S_2091, a component of the A1S_2088-A1S_2091 polycistronic operon predicted to code for a type I chaperone/usher pilus assembly system, abolished surface motility and pellicle formation but significantly enhanced biofilm formation on plastic by bacteria cultured under darkness. Based on these observations, the A1S_2088-A1S_2091 operon was named the <u>p</u> hoto- <u>r</u> egulated <u>p</u> ilus ABCD ( prpABCD ) operon, with A1S_2091 coding for the PrpA pilin subunit...

Antibiotic resistance has become increasingly prevalent over the past few decades, and this combined with a dearth in the development of new classes of antibiotics to treat multidrug resistant Gram-negative infections has led to a significant global health problem and the increased usage of colistin as the last resort antibiotic. Colistin, however, presents dose dependent toxicity in the clinic. One potential approach to combatting this problem is the use of an antibiotic adjuvant, a compound that is non-toxic to the bacteria, that enhances the potency of colistin and ultimately allows for reducing dosing...

The emergence of infections associated to new antimicrobial resistance in Acinetobacter baumannii (Ab) genotypes represents a major challenge. In this context, this study aimed to determine the diversity of resistance mechanisms and investigate clonal dissemination and predominant sequence types (STs) in multidrug-resistant Ab strains of clinical (tracheal aspirate, n = 17) and environmental (surface, n = 6) origins. Additionally, the major clones found in clinical (A) and environmental (H) strains had their complete genomes sequenced...

Sediment microbial communities from plain river networks exert different effects on pollutant transformation and migration in lake basins. In this study, we examined millions of Illumina reads (16S rRNA gene amplicons) to compare lake, lake wetland, and estuary bacterial communities through a technically consistent approach. Results showed that bacterial communities in the sampled lake sediments had the highest alpha-diversity (Group B), than in sampled lake wetland sediments and estuary sediments. Proteobacteria was the most abundant (more than 30%) phyla in all the sediments...

Outer membrane complex (OMC) vaccines, which contain antigens from the bacterial outer membrane, have been developed for multiple Gram-negative bacteria. However, OMC vaccines demonstrate high endotoxin activity due to the presence of lipopolysaccharide in the bacterial outer membrane, thus precluding their use in humans. We isolated OMCs from an LPS-deficient strain of A. baumannii (IB010) which completely lacks LPS due to a mutation in the lpxD gene. OMCs from IB010 demonstrated a more than 10,000-fold reduction in endotoxin activity compared to OMCs from wild type A...

A capsular polysaccharide (CPS) was isolated from strain MAR13-1452 of an emerging pathogen Acinetobacter baumannii and assigned type K125. The following structure of the CPS was established by sugar analysis, Smith degradation, and 1D and 2D 1 H and 13 C NMR spectroscopy: Proteins encoded by the KL125 gene cluster in the genome of MAR13-1452, including three glycosyltransferases, were assigned roles in the biosynthesis of the K125 CPS.

Acinetobacter baumannii has emerged as a leading nosocomial pathogen, infecting a wide range of anatomic sites including the respiratory tract and the bloodstream. In addition to being multi-drug resistant, little is known about the molecular basis of A. baumannii pathogenesis. To better understand A. baumannii virulence, a combination of a transposon-sequencing (TraDIS) screen and the neutropenic mouse model of bacteremia was used to identify the full set of fitness genes required during bloodstream infection...