Search results for "bacteri"

Outbreak of CTX-M-15-producing Klebsiella pneumoniae of sequence type 199 in a Latvian teaching hospital

2010

Dumpis U, Iversen A, Balode A, Saule M, Miklasevics E, Giske CG. Outbreak of CTX-M-15-producing Klebsiella pneumoniae of sequence type 199 in a Latvian teaching hospital. APMIS 2010; 118: 713–6. Previous studies on the epidemiology of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae in Latvia are lacking. ESBL-producing Klebsiella pneumoniae (n = 32) were subjected to pulsed-field gel electrophoresis (PFGE) and selected isolates to multi-locus sequence typing (MLST). Species identification and susceptibility testing were performed using VITEK2, and sequencing of blaCTX-M was performed in selected isolates. PFGE revealed one major clone (n = 23), with most of the isolates de…

The power and limitations of genomic surveillance of bacteria.

2019

Physiological engineering of Pseudomonas aurantiaca antimicrobial activity: effects of sodium chloride treatment

2012

The influence of sodium chloride (NaCl) treatment on the antifungal activity of the bacterium Pseudomonas aurantiaca, a producer of biopesticide for vegetable plants, was investigated. It was shown that an increase in the NaCl concentration in incubation solutions from 1 M to 3 M led to a significant increase in the antifungal activity of this bacterium. Antifungal activity continued to increase with prolonged treatment of bacteria in fresh nutrient medium from 72 h to 96 h. These findings could be very important for the further development of biotechnological processes directed not only to the production of new active biopesticides but also of other valuable resources.

2021

The genus Centaurea is recognized in folk medicine for anti-inflammatory, anti-itch, antitussive, purgative, astringent, and tonic activities. To study the chemical determinant for antimicrobial activity essential oils (EOs), five Centaurea species were analyzed including: C. scoparia, C. calcitrapa, C. glomerata, C. lipii and C. alexandrina. Conventional hydro-distillation (HD) and microwave-assisted extraction (MAE), as new green technologies, were compared for the extraction of essential oils. GC/MS analysis identified 120 EOs including mostly terpenoid except from C. lipii and C. alexandrina in which nonterpenoids were the major constituents. Major terpenoids included spathulenol, caryo…

Out of the Abyss: Genome and Metagenome Mining Reveals Unexpected Environmental Distribution of Abyssomicins.

2020

AbstractNatural products have traditionally been discovered through the screening of culturable microbial isolates from all sort of environments. The sequencing revolution allowed the identification of dozens of biosynthetic gene clusters (BGCs) within single bacterial genomes, either from cultured or uncultured strains. However, we are still far from fully exploiting the microbial reservoir, as most of the species are non-model organisms with complex regulatory systems and yet recalcitrant to be engineered. Today, genomic and metagenomic data produced by laboratories worldwide covering the most different natural and artificial environments on Earth, are an invaluable source of raw informat…

Identification of Shigella sonnei biotype g isolates carrying class 2 integrons in Italy in 2001-2003

2005

ABSTRACT Phenotyping and genotyping have been carried out on 64 epidemic and sporadic isolates of Shigella sonnei identified in Italy in the years 2001 to 2003. Class 2 integron carriage has been also investigated. Isolates from four of the five outbreaks and four of six sporadic cases were biotype g , pulsed-field gel electrophoresis type B, and class 2 integron positive, suggesting emergence and spread of an epidemic clone in Italy.

Functional gene pyrosequencing reveals core proteobacterial denitrifiers in boreal lakes

2015

Denitrification is an important microbial process in aquatic ecosystems that can reduce the effects of eutrophication. Here, quantification and pyrosequencing of nirS, nirK, and nosZ genes encoding for nitrite and nitrous oxide reductases was performed in sediment samples from four boreal lakes to determine the structure and seasonal stability of denitrifying microbial populations. Sediment quality and nitrate concentrations were linked to the quantity and diversity of denitrification genes, the abundance of denitrifying populations (nirS and nosZ genes) correlated with coupled nitrificationdenitrification (Dn), and the denitrification of the overlying water NO3 − (Dw) correlated with the n…

Phylogenetic Distribution of Polysaccharide-Degrading Enzymes in Marine Bacteria

2021

Deconstruction is an essential step of conversion of polysaccharides, and polysaccharide-degrading enzymes play a key role in this process. Although there is recent progress in the identification of these enzymes, the diversity and phylogenetic distribution of these enzymes in marine microorganisms remain largely unknown, hindering our understanding of the ecological roles of marine microorganisms in the ocean carbon cycle. Here, we studied the phylogenetic distribution of nine types of polysaccharide-degrading enzymes in marine bacterial genomes. First, we manually compiled a reference sequence database containing 961 experimentally verified enzymes. With this reference database, we annota…

Yaws re-emergence and bacterial drug resistance selection after mass administration of azithromycin: a genomic epidemiology investigation

2020

Summary Background In a longitudinal study assessing the WHO strategy for yaws eradication using mass azithromycin treatment, we observed resurgence of yaws cases with dominance of a single JG8 sequence type and emergence of azithromycin-resistant Treponema pallidum subspecies pertenue (T p pertenue). Here, we analyse genomic changes in the bacterial population using samples collected during the study. Methods We did whole bacterial genome sequencing directly on DNA extracted from 37 skin lesion swabs collected from patients on Lihir Island, Papua New Guinea, between April 1, 2013, and Nov 1, 2016. We produced phylogenies and correlated these with spatiotemporal information to investigate t…

Biocontrol of the Major Plant Pathogen Ralstonia solanacearum in Irrigation Water and Host Plants by Novel Waterborne Lytic Bacteriophages

2019

Three new lytic bacteriophages were found to effectively control the pathogen Ralstonia solanacearum, a quarantine bacterium in many countries, and causative agent of bacterial wilt, one of the most important vascular plant diseases. Bacterial wilt management has been carried out with fluctuating effects, suggesting the need to find alternative treatments. In this work, three lytic phages were isolated from environmental water from geographically distant regions in Spain. They proved to specifically infect a collection of R. solanacearum strains, and some of the closely related pathogenic species Ralstonia pseudosolanacearum, without affecting non-target environmental bacteria, and were abl…