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1

Lactobacillus strains belonging to Casei group display various adherence to enterocytes and mucus

100%
Markowicz C., Schmidt M. T.
Acta Scientiarum Polonorum. Technologia Alimentaria
|
2015
|
tom 14
|
nr 3
Background. The ability of lactobacilli to adhere to the surface of the intestine is an important functional characteristic which can largely determine the effective colonization of the intestinal tract by probiotics. The following study compares the adhesion efficiency of the twenty strains of Lactobacillus genus belonging to Casei group to the Caco-2 cells and gastrointestinal mucus. Material and methods. Twenty isolates of lactobacilli belonging to Casei group were tested. The ability of bacterial cells to adhere to mucus was examined using adhesion assay to gastrointestinal mucus. Obtained results were compared with adhesion efficiency to Caco-2 cells. Phylogenetic relationship between isolates was analysed by rep-PCR. Results. The results showed large differences in adhesion efficiency between strains, as well as differences in the efficiency of adhesion to the intestinal epithelial cells and mucus. Group similarity highlighted by a rep- PCR technique does not correspond with groups of similarity in terms of the characteristics of the ability to adhere to mucus or the epithelial cells of intestinal tract. Conclusions. Strains having a high adhesion efficiency to enterocytes do not always show a high adhesion efficiency to the mucus. This may indicate the presence of different and multiple factors responsible for adhesion efficiency of Lactobacillus group Casei strains to epithelial cells and mucus.
2

Zastosowanie egzopolisacharydów produkowanych przez bakterie kwasu mlekowego

100%
Markowicz C., Schmidt M. T.
Przemysł Spożywczy
|
2015
|
tom 69
|
nr 11
3

Exopolysaccharides produced by Lactobacillus rhamnosus KL 53A and Lactobacillus casei Fyos affect their adhesion to enterocytes

81%
Konieczna C., Slodzinski M., Schmidt M. T.
Polish Journal of Microbiology
|
2018
|
tom 67
|
nr 3
Probiotics promote and help to maintain beneficial microbiota composition of the gastrointestinal tract ecosystem and have a positive impact on the host’s health. Production of exopolysaccharides is an important feature of probiotic lactobacilli. It increases the chance of their survival in the gastrointestinal tract and promotes adhesion to the epithelium; therefore, exopolysaccharides are important for the process of colonization. Two lactic acid bacteria strains were used in this study: Lactobacillus rhamnosus KL 53A and Lactobacillus casei Fyos. Exopolysaccharides were isolated from bacterial cells and their monosaccharide composition was examined using liquid chromatography. The influence of exopolysaccharides on lactobacilli adhesion to enterocytes was studied after deglycosylation of the bacterial cells and incubation with the selected intestinal microbiota strains that metabolize polysaccharides – Faecalibacterium prausnitzii DSM 17677 and Blautia luti DSM 14534. Both deglycosylation and incubation with polysaccharide metabolizing strains influenced the ability of probiotic strains to adhere to enterocytes. Enzymatic deglycosylation decreased adhesion efficiency of L.rhamnosus KL 53A; however, co-incubation of both lactobacillus strains with F. prausnitzii DSM 17677 resulted in an increase of their adhesion efficiency. Exopolysaccharides are important adhesins of Lactobacillus spp. that influence their ability to colonize gut epithelium. Other members of gut microbiota can modify the adhesion property in situ; therefore the composition and metabolic state of commensal bacteria may influence their probiotic action.
4

Lactobacillus spp. belonging to the Casei group display a variety of adhesins

81%
Konieczna C., Olejnik-Schmidt A., Schmidt M. T.
Acta Scientiarum Polonorum. Technologia Alimentaria
|
2018
|
tom 17
|
nr 1
5

SpaCBA sequence instability and its relationship to the adhesion efficiency of Lactobacillus casei group isolates to Caco - 2 cells

81%
Markowicz C., Olejnik-Schmidt A., Borkowska M., Schmidt M. T.
Acta Biochimica Polonica
|
2014
|
tom 61
|
nr 2
 The ability to adhere to enterocytes is one of the key features of probiotics. This process involves a number of factors, among which the important role of pili was demonstrated. Some Lactobacillus species are confirmed to have heterotrimeric spaCBA type pili. The aim of this study was to identify spaCBA pili in strains of selected Lactobacillus spp. and assess the impact of their presence and sequence polymorphism on the adhesion of these strains to enterocytes. Total 20 bacterial strains of L. rhamnosus, L. casei and L. paracasei were tested. The presence of pilus specific proteins coding genes spaA, spaB and spaC was verified by PCR in order to identify the presence of sequence polymorphism in the genes possibly affecting the structure of the spaCBA pilus. To correlate spaCBA polymorphism to adhesion capability the adhesion assay was carried out using Caco-2 cell line. The effectiveness of the adhesion was measured using a scintillation counter. The Lactobacillus strains analyzed showed the adhesion to Caco-2 enterocytes capability from 0.6% to 19.6%. The presence of spaCBA pili is a factor increasing the adhesion efficiency of Lactobacillus spp. to Caco-2 enterocytes. Lack of these structures on the surface of bacterial cells results in the reduction in adhesion efficiency, indicating its important role in the adhesion process. But not in all cases the correlation between the presence of protein spaCBA structures and adhesion efficiency was observed, what may indicate the important role of other factors in adhesion of analyzed strains to Caco-2 cells.
6

Orphan nuclear hormone receptor NR4A1 interacts with HPV16 E2 regulatory protein

80%
Olejnik-Schmidt A. K., Schmidt M. T., Gozdzicka-Jozefiak A.
Cellular and Molecular Biology Letters
|
2006
|
tom 11
|
nr 1
The human NR4A1 orphan receptor is a member of the TR3 steroid receptor superfamily, which binds DNA at the NBRE and NurRE responsive elements. The TR3 receptors are involved in the regulation of differentiation, proliferation and apoptosis. We report that NR4A1 interacts with human papillomavirus type 16 (HPV16) E2 protein — a key papillomavirus regulatory factor. This interaction might be involved in the transcription regulation of the HPV16 genes and the regulation of infected cell homeostasis.
7

The HPV16 E2 transcriptional regulator mode of action depends on the physical state of the viral genome

80%
Schmidt M. T., Olejnik A. K., Gozdzicka-Jozefiak A.
Acta Biochimica Polonica
|
2005
|
tom 52
|
nr 4
Human papillomavirus (HPV) infection is a major risk factor for the development of cervical cancer. The HPV-induced immortalization of epithelial cell usually requires integration of the viral DNA into the host cell genome. The integration event causes disruption of the E2 gene and this is followed by overexpression of the E6 and E7 oncoproteins. The E2 protein is a transcription factor that regulates expression of the E6 and E7 oncoproteins by binding to four sites within the viral long control region. We used an in vitro cell culture model to explore the role of the E2 protein in the transcriptional control of the HPV16 long control region. Employing transient and stable transfection experiments we simulated the episomal and integrated states of the viral genome, respectively. We show that the E2 protein up-regulates E6/E7 transcription from episomal DNA but represses it in the case of integrated DNA. The activator function of the E2 protein seems to counteract the repressive chromatin structure formed over episomal DNA. Steroid hormones and retinol also modulate oncogene transcription differently depending on the physical structure of the viral DNA. Our data suggest regulatory mechanisms involving interactions between the E2 protein and nuclear hormone receptors.
8

Expression of bacteriocin divercin AS7 in heterologous system Pichia methanolica

71%
Olejnik-Schmidt A., Sowinska A., Schmidt M. T., Sip A., Grajek W.
Acta Biochimica Polonica
|
2006
|
tom 53
|
nr Supplement 1
9

Evaluation of quantitative PCR measurement of bacterial colonization of epithelial cells

71%
Schmidt M. T., Olejnik-Schmidt A. K., Myszka K., Borkowska M., Grajek W.
Polish Journal of Microbiology
|
2010
|
tom 59
|
nr 2
89-93
Microbial colonization is an important step in establishing pathogenic or probiotic relations to host cells and in biofilm formation on industrial or medical devices. The aim of this work was to verify the applicability of quantitative PCR (Real-Time PCR) to measure bacterial colonization of epithelial cells. Salmonella enterica and Caco-2 intestinal epithelial cell line was used as a model. To verify sensitivity of the assay a competition of the pathogen cells to probiotic microorganism was tested. The qPCR method was compared to plate count and radiolabel approach, which are well established techniques in this area of research. The three methods returned similar results. The best quantification accuracy had radiolabel method, followed by qPCR. The plate count results showed coefficient of variation two-times higher than this of qPCR. The quantitative PCR proved to be a reliable method for enumeration of microbes in colonization assay. It has several advantages that make it very useful in case of analyzing mixed populations, where several different species or even strains can be monitored at the same time.
10

Impact of DNA microarray data transformation on gene expression analysis - comparison of two normalization methods

61%
Schmidt M. T., Handschuh L., Zyprych J., Szabelska A., Olejnik-Schmidt A. K., Siatkowski I., Figlerowicz M.
Acta Biochimica Polonica
|
2011
|
tom 58
|
nr 4
Two-color DNA microarrays are commonly used for the analysis of global gene expression. They provide information on relative abundance of thousands of mRNAs. However, the generated data need to be normalized to minimize systematic variations so that biologically significant differences can be more easily identified. A large number of normalization procedures have been proposed and many softwares for microarray data analysis are; available. Here, we have applied two normalization methods (median and loess) from two packages of microarray data analysis softwares. They were examined using a sample data set. We found that the number of genes identified as differentially expressed varied significantly depending on the method applied. The obtained results, i.e. lists of differentially expressed genes, were consistent only when we used median normalization methods. Loess normalization implemented in the two software packages provided less coherent and for some probes even contradictory results.In general, our results provide an additional piece of evidence that the normalization method can profoundly influence final results of DNA microarray-based analysis. The impact of the normalization method depends greatly on the algorithm employed. Consequently, the normalization procedure must be carefully considered and optimized for each individual data set.
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