Variability of resistance plasmids in coagulase-negative staphylococci and their importance as a reservoir of antimicrobial resistance
In this study, we analyzed plasmid content in 62 strains belonging to 10 CoNS species of human and veterinary origin. In 48 (77%) strains analyzed, 107 different plasmids were detected, and only some of them showed similarities with plasmids found previously. In total, seven different antimicrobial-resistance genes carried by plasmids were identified. Five of the CoNS staphylococci carried plasmids identical with either those of other CoNS species tested, or a well characterized Staphylococcus aureus strain COL, suggesting plasmid dissemination through horizontal transfer. To demonstrate the possibility of horizontal trans...
Source: Research in Microbiology - November 29, 2018 Category: Microbiology Source Type: research
Editorial board
Publication date: November 2018Source: Research in Microbiology, Volume 169, Issue 9Author(s): (Source: Research in Microbiology)
Source: Research in Microbiology - November 25, 2018 Category: Microbiology Source Type: research
Relic DNA Does Not Obscure the Microbial Community of Paddy Soil Microbial Fuel Cells
In this study the effect of the MFCs on the soil microbial community composition within the soil profile and the influence of relic DNA were investigated. Microbial community analysis revealed that the MFCs deployment significantly influenced the community composition within the soil profile. The phylum Proteobacteria (34.4% vs 23.6%) and the class Deltaproteobacteria (16.8% vs 5.9%) significantly increased in the MFCs compared to the control, while the phylum Firmicutes (24.0% vs 28.7%) and the class Sphingobacteria (5.3% vs 7.0%) were more abundant in the control. Furthermore, the archaeal phyla Euryarchaeota (40.7% vs 5...
Source: Research in Microbiology - November 21, 2018 Category: Microbiology Source Type: research
Role of the Klebsiella pneumoniae TolC porin in antibiotic efflux
Publication date: Available online 20 November 2018Source: Research in MicrobiologyAuthor(s): Ramkumar Iyer, Samir H. Moussa, Ruben Tommasi, Alita A. MillerAbstractThe major Gram-negative gated efflux channel TolC has been extensively characterized in Escherichia coli but there is minimal information about Klebsiella pneumoniae TolC. Using an arabinose-inducible plasmid-based expression system, we show that the K. pneumoniae TolC complements the efflux defect in an E. coli K-12 ΔtolC strain, restoring wild-type levels of resistance towards most antibiotics suggesting that it can interact with the E. coli AcrB efflux pump....
Source: Research in Microbiology - November 21, 2018 Category: Microbiology Source Type: research
Expressing Cytotoxic Compounds in Escherichia coli Nissle 1917 for Tumor-targeting Therapy
The objective of this study was to establish a tumor-targeting therapy system using the genetically engineered EcN for targeted delivery of cytotoxic compounds, including colibactin, glidobactin and luminmide. Biosynthetic gene clusters of these cytotoxic compounds were introduced into EcN and the corresponding compounds were detected in the resultant recombinant EcN strains. The recombinant EcN showed significant cytotoxic activity in vitro and in vivo as well, and significantly suppressed the tumor growth. Together, this study confirmed efficient tumor-targeting colonization of EcN and demonstrated its potentiality in th...
Source: Research in Microbiology - November 15, 2018 Category: Microbiology Source Type: research
Quorum-sensing systems trigger catalase expression to reverse the oxyR deletion-mediated VBNC state in Salmonella typhimurium
In this study, conditioned media containing autoinducer collected from the wild type strain can restore the growth of low concentrations of the oxyR mutant strain on LB plates, and S. typhimurium collected from the plate has higher catalase activity than that from the broth, suggesting that a quorum-sensing system can trigger catalase expression to resuscitate the organism from the VBNC state independent of the OxyR regulon. We discovered a novel catalase (STM14_2049, Cat) whose expression is strictly concentration-dependent. The purified Cat protein has obvious catalase activity in vitro and in vivo and can restore the gr...
Source: Research in Microbiology - November 7, 2018 Category: Microbiology Source Type: research
Low-level thiocyanate concentrations impact on iron oxidation activity and growth of leptospirillum ferriphilum through inhibition and adaptation
Publication date: Available online 2 November 2018Source: Research in MicrobiologyAuthor(s): Catherine J. Edward, Athanasios Kotsiopoulos, Susan T.L. HarrisonAbstractLeptospirillum ferriphilum is the dominant iron-oxidising bacterium in traditional microbial communities utilised in bioprocesses for gold recovery from sulfidic minerals. Ferrous iron oxidation activity and growth of unadapted and thiocyanate-adapted L. ferriphilum HT was studied in batch culture across increasing thiocyanate (SCN-) concentrations in the range 0 – 2 mg/L to assess the feasibility of recycling remediated cyanidation wastewaters. Thiocyanate ...
Source: Research in Microbiology - November 3, 2018 Category: Microbiology Source Type: research
Centennial Celebration of the Bacteriophage Research
Publication date: Available online 2 November 2018Source: Research in MicrobiologyAuthor(s): Laurent Debarbieux, Patrick Forterre, Mart Krupovic, Mzia Kutateladze, David Prangishvili (Source: Research in Microbiology)
Source: Research in Microbiology - November 3, 2018 Category: Microbiology Source Type: research
The Phosphotransferase System Gene ptsH Plays an Important Role in MnSOD Production, Biofilm Formation, Swarming motility, and Root Colonization in Bacillus cereus 905
In this study, we found that the deletion of the ptsH gene, which encodes the histidine-phosphorylatable protein (HPr), a component of the phosphotransferase system (PTS), causes a decrease of about 60% in the MnSOD2 expression. Evidences indicate that the ptsH dramatically influences resistance to oxidative stress, glucose uptake, as well as biofilm formation and swarming motility of B. cereus 905. Root colonization assay demonstrated that ΔptsH is defective in colonizing wheat roots, while complementation of the sodA2 gene could partially restore the ability in utilization of arabinose, a non-PTS sugar, and root coloniz...
Source: Research in Microbiology - November 3, 2018 Category: Microbiology Source Type: research
Editorial board
Publication date: September–October 2018Source: Research in Microbiology, Volume 169, Issues 7–8Author(s): (Source: Research in Microbiology)
Source: Research in Microbiology - October 13, 2018 Category: Microbiology Source Type: research
Stratification of microbial communities throughout a biological sulphate reducing up-flow anaerobic packed bed reactor, revealed through 16S metagenomics
Publication date: Available online 9 October 2018Source: Research in MicrobiologyAuthor(s): Tomas Hessler, Susan T.L. Harrison, Robert J. HuddyAbstractBiological sulphate reduction (BSR) is a promising low-cost treatment of acid rock drainage effluents. In this paper, the system performance and microbial ecology of a lactate supplemented BSR up-flow anaerobic packed bed reactor (UAPBR) are evaluated across reactor height and compared to a continuous stirred tank reactor (CSTR). The biomass concentrations of planktonic and biofilm communities were quantified and subsequently characterised by 16S rRNA gene amplicon sequencin...
Source: Research in Microbiology - October 9, 2018 Category: Microbiology Source Type: research
Structural and functional profiles of the gut microbial community in polycystic ovary syndrome with insulin resistance (IR-PCOS): a pilot study
In this study, next-generation sequencing based on the 16S rRNA gene was used to compare the gut microbial composition of women with IR-PCOS (n = 9, PCOS with insulin resistance), NIR-PCOS (n = 8, PCOS alone) and healthy controls (n = 8, HC). We assessed that the composition of the gut microbial communities in NIR-PCOS and IR-PCOS patients were significantly altered. The family Bacteroidaceae was prolific in the NIR-PCOS group and reached its highest level in the IR-PCOS group, while the Prevotellaceae dramatically decreased in PCOS patients, especially in the IR-PCOS group. Subsequent correlation analysis revealed that th...
Source: Research in Microbiology - October 5, 2018 Category: Microbiology Source Type: research
Introduction of bifunctional alcohol/acetaldehyde dehydrogenase gene (adhE) in Fructobacillus fructosus settled its fructophilic characteristics
In this study, the bifunctional alcohol/acetaldehyde dehydrogenase gene (adhE) from Leuconostoc mesenteroides NRIC 1541T was cloned into a plasmid and transferred to Fructobacillus fructosus NRIC 1058T. Differences in biochemical characteristics between the parental strain (NRIC 1058T) and the transformants were compared. Strain 1-11, transformed with the adhE gene, did not show any fructophilic characteristics, and the strain grew well on D-glucose without external electron acceptors. Accumulation of acetic acid, which was originally seen in the parental strain, was replaced with ethanol in the transformed strain. Further...
Source: Research in Microbiology - October 4, 2018 Category: Microbiology Source Type: research
Bacterial Efflux Transporters in the Limelight
Publication date: Available online 15 September 2018Source: Research in MicrobiologyAuthor(s): Klaas Martinus Pos (Source: Research in Microbiology)
Source: Research in Microbiology - September 15, 2018 Category: Microbiology Source Type: research
What is the minimum length of gltA gene required for phylogenetic analyzes in Bartonella?
Publication date: Available online 12 September 2018Source: Research in MicrobiologyAuthor(s): Alexandro Guterres, Jonathan Gonçalves, Elba Regina Sampaio de LemosAbstractBartonellosis is an emerging serious diseases of zoonotic relevance caused by an expanding number of recently discovered species of Bartonella. Many studies use partial gltA gene sequencing as the method of choice for species attribution, and a plethora of studies have utilized only this gene to describe Bartonella diversity. We observe a lack of correspondence between the phylogenies constructed using the complete gltA gene sequences and the small gene ...
Source: Research in Microbiology - September 12, 2018 Category: Microbiology Source Type: research
