Comparative analysis of biofilm structures in Salmonella Typhimurium DMC4 strain and its dam and seqA gene mutants using Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy methods.

It is well-established that the dam and seqA genes act in the biofilm production in Salmonella. However, the molecular basis underlying this activity remains unexplored. This study aims to address this gap in the literature.

[Effect of Quorum Sensing Systems on Biofilm Formation and Virulence in Salmonella].

In recent years, as the paradigm of communication between cells has been clarified, the ability of bacteria to change their gene expression patterns in response to various extracellular signals has attracted great interest. In particular, intracellular and intercellular communication between bacterial populations, called quorum sensing (QS), is essential for coordinating physiological and genetic activities. QS studies are critical, particularly in elucidating the regulatory mechanisms of infectious processes in food-borne pathogens.

Genomic analysis of Salmonella bacteriophages revealed multiple endolysin ORFs and importance of ligand-binding site of receptor-binding protein.

Salmonella is a prevalent foodborne pathogen causing millions of global cases annually. Antimicrobial resistance is a growing public health concern, leading to search for alternatives like bacteriophages. A total of 97 bacteriophages, isolated from cattle farms (n = 48), poultry farms (n = 37), and wastewater (n = 5) samples in Türkiye, were subjected to host-range analysis using 36 Salmonella isolates with 18 different serotypes.

Characteristics of Bacterial Biofilm Formation in Nasolacrimal Silicone Tubes Post-dacryocystorhinostomy.

Purpose: To examine the biofilm formation characteristics of bacteria identified at the genus level in samples obtained from silicone tubes after dacryocystorhinostomy surgery.

Methods: In the study involving consecutive patients who underwent dacryocystorhinostomy surgery at Ankara Bilkent City Hospital and whose silicone tubes were removed six months after surgery, between January 2023 and May 2023; the tubes were placed in glycerol-PBS (phosphate buffered saline) solution and cultured on descriptive selective media at the genus level. The biofilm-forming properties of the obtained isolates were examined in solid-air and liquid-air interphases.

Comparative global gene expression analysis of biofilm forms of Salmonella Typhimurium ATCC 14028 and its seqA mutant.

In this study, comparative transcriptomic analyzes (mRNA and miRNA) were performed on the biofilm forms of S. Typhimurium ATCC 14028 wild-type strain and its seqA gene mutant in order to determine the regulation characteristics of the seqA gene in detail. The results of global gene expression analyses showed an increase in the expression level of 54 genes and a decrease in the expression level of 155 genes (p < 0.

What makes another life possible in bacteria? Global regulators as architects of bacterial biofilms.

Biofilm structures are the main mode of evolutionary reproductive adaptation of bacteria, and even these features alone, are sufficient to make them the focus of genetic and physiological studies. As this life form is a multicellular-like life form coordinated by genetic and physiological programming, it is quite different from the planktonic form. In bacterial biofilms, which are often composed of more than one species in nature, there is a clear division of labor, nutrient channels, and a language (signaling) established between the cells forming the biofilm.

Phenotypic impacts and genetic regulation characteristics of the DNA adenine methylase gene (dam) in Salmonella Typhimurium biofilm forms.

In this study, transcriptional level gene expression changes in biofilm forms of Salmonella Typhimurium ATCC 14028 and its dam mutant were investigated by performing RNAseq analysis. As a result of these analyzes, a total of 233 differentially expressed genes (DEGs) were identified in the dam mutant, of which 145 genes were downregulated and 88 genes were upregulated compared to the wild type. According to data from miRNA sequence analysis, of 13 miRNAs differentially expressed in dam mutant, 9 miRNAs were downregulated and 4 miRNAs were upregulated.

Genetic Diversity and Characterization of Plant Growth-Promoting Effects of Bacteria Isolated from Rhizospheric Soils.

Plant growth-promoting rhizobacteria (PGPR) have the potential to make a significant contribution to the development of sustainable agricultural systems. Generally, PGPRs function in three different ways, summarized as the synthesis of certain compounds for plants, facilitating the uptake of certain nutrients from the soil and protecting plants from diseases. This study aims to isolate plant growth-promoting bacteria from different plant rhizospheres from Ankara province, to reveal their genetic diversity, and to determine their plant growth-promoting properties.

Determination of an effective agent combination using nisin against Salmonella biofilm.

This present study aims to determine the lowest concentration effects of the assayed different antibiotics; antimicrobial agents alone and their combinations with nisin were investigated to prevent the biofilm formation and break down the biofilm structure of Salmonella. While the combination of nisin and EDTA showed a synergistic effect against Salmonella strain, chlorhexidine digluconate and streptomycin with nisin showed a partial synergetic effect; citric acid and sulfonamides with nisin showed an indifferent effect. The use of citric acid and chlorhexidine digluconate alone was very effective in Salmonella inhibition.

The role of bcsE gene in the pathogenicity of Salmonella.

The effects of the bcsE gene and BcsE protein on bacterial physiology and pathogenicity in SalmonellaTyphimurium and Salmonella Group C1 were investigated. It was observed that biofilm and pellicle formation did not occur in the bcsE gene mutants of wild-type strains. Besides, the 'rdar' (red, dry, rough) biofilm morphotype in wild-type strains changed significantly in the mutants.

Identification and characterization of lytic bacteriophages specific to foodborne pathogenic O157:H7.

The objective of this study was to identify and characterize five different lytic bacteriophages specific to O157:H7. vB_EcoM-P12, vB_EcoM-P13, vB_EcoM-P23, and vB_EcoM-P34 phages belonged to the Myoviridae family and vB_EcoS-P24 phage was in the Siphoviridae family. Their plaque sizes changed between 0.

Regulation of biofilm formation by marT in Salmonella Typhimurium.

In this study, we aimed at identifying the regulatory role of marT gene, known as the regulator of misL, on 15 different biofilm-related genes in S. Typhimurium 14028 strain. We also tested the strains for their ability to form biofilm and determined the adherence characteristics of the wild type and the mutant strains of the organism on Caco-2 and HEp-2 cells.

Characterization of SE-P3, P16, P37, and P47 bacteriophages infecting Salmonella Enteritidis.

The aim of this study was to identify and characterize the SE-P3, P16, P37, and P47 phages infecting Salmonella Enteritidis. Transmission electron microscopy analysis showed that the SE phages belonged to the Myoviridae or Siphoviridae family and had plaque sizes between 0.622 ± 0.

Investigation of the effect of different environmental conditions on biofilm structure of Salmonella enterica serotype Virchow via FTIR spectroscopy.

This study aims to describe the content of polymeric matrix components under different incubation temperatures and pH levels. Optimal biofilm production of 15 S. Virchow isolates occurred following the incubation in LB for 72 h, at pH 6.

Inhibition and eradication of Salmonella Typhimurium biofilm using P22 bacteriophage, EDTA and nisin.

P22 phage >10 PFU ml could be used to inhibit Salmonella Typhimurium biofilm formation by 55-80%. Concentrations of EDTA >1.25 mM and concentrations of nisin >1,200 µg ml were also highly effective in reducing S.

Effects of dam and seqA genes on biofilm and pellicle formation in Salmonella.

In this study, the effects of dam and seqA genes on the formation of pellicle and biofilm was determined using five different Salmonella serovars S. Group C1 (DMC2 encoded), S. Typhimurium (DMC4 encoded), S.

Innovative approaches to nisin production.

Nisin is a bacteriocin produced by Lactococcus lactis that has been approved by the Food Drug Administration for utilization as a GRAS status food additive. Nisin can inhibit spore germination and demonstrates antimicrobial activity against Listeria, Clostridium, Staphylococcus, and Bacillus species. Under some circumstances, it plays an immune modulator role and has a selective cytotoxic effect against cancer cells, although it is notable that the high production cost of nisin-a result of the low nisin production yield of producer strains-is an important factor restricting intensive use.

Does subinhibitory concentrations of clinically important antibiotic induce biofilm production of Enterococcus faecium strains?

Biofilm structures are the most resistant form of active microorganisms against sanitation, disinfection, and sterilization processes. One of the specific properties of biofilm is the development of antibiotic resistance that can be up to 1,000-fold greater than planktonic cells. Enterococcus faecium is a human pathogen that causes nosocomial bacteremia and at the present time, it is well known that most of the chronic infections are biofilm-based.

Identification of genomic heterogeneity among Lactococcus lactis strains by plasmid profiling, PFGE and 16S rDNA sequence analysis.

Lactococcus lactis strains are used commonly as starters, which contribute to desirable flavour and texture properties known as strain-specific, in dairy industry. Genomic heterogeneity of 30 L. lactis strains originating from Turkey and characterized phenotypically were investigated in this study.

Characterization of antibiotic resistance in Salmonella enterica isolates determined from ready-to-eat (RTE) salad vegetables.

In the last decade, ready-to-eat (RTE) salad vegetables are gaining increasing importance in human diet. However, since they are consumed fresh, inadequate washing during processing can bring on some foodborne illnesses, like salmonellosis, since these food items have natural contamination from soil and water. During 2009-2010, a total of 81 samples were purchased arbitrarily from local markets in Ankara, and were examined for Salmonella contamination.

Immobilization of nisin producer Lactococcus lactis strains to chitin with surface-displayed chitin-binding domain.

In this study, nisin producer Lactococcus lactis strains displaying cell surface chitin-binding domain (ChBD) and capable of immobilizing to chitin flakes were constructed. To obtain ChBD-based cell immobilization, Usp45 signal sequence with ChBD of chitinase A1 enzyme from Bacillus circulans was fused with different lengths of PrtP (153, 344, and 800 aa) or AcmA (242 aa) anchors derived from L. lactis.

Purification and partial characterization of bacteriocin produced by Lactococcus lactis ssp. lactis LL171.

Lactic acid bacteria (LAB) are possessing ability to synthesize antimicrobial compounds (like bacteriocin) during their growth. In this regard, novel bacteriocin compound secreting capability of LAB isolated from Tulum Cheese in Turkey was demonstrated. The synthesized bacteriocin was purified by ammonium sulphate precipitation, dialysis and gel filtration.

Partial characterization of bacteriocins produced by two Lactobacilus strains with probiotic properties.

The probiotic characteristics of Lactobacillus brevis BG18 and Lb. plantarum BG33, isolated from traditional Turkish Tulum cheese were assessed. These two bacteriocinproducer strains exhibited good probiotic characteristics such as resistance in media containing 0.

Thermal inactivation kinetics of Lactococcus lactis subsp. lactis bacteriophage pll98-22.

Survival curves of Lactococcus lactis subsp. lactis bacteriophage pll98 inactivated by heat were obtained at seven temperature values (50-80 degrees C) in M17 broth and skim milk. Deviations from first-order kinetics in both media were observed as sigmoidal shapes in the survival curves of pll98.