Biological activity of surfactins - a case of a biosurfactant produced by Bacillus subtilis PCM 1949

Biosurfactants are microbial surface active compounds which, contrary to synthetic surfactants, are natural in origin, biodegradable and less toxic to a human organism. For that reason, there is a great research potential in studies aimed at their purification, finding potential ways of their utilization and decreasing their production costs. This paper demonstrates the process of isolating and purifying a surfactin synthesized by Bacillus subtilis PCM 1949. Surfactin samples were prepared by a classical organic solvent extraction and were studied using mass spectrometry (MS). Analysis of the susceptibility profile of microorganisms utilized in the diffusion-plate tests demonstrated that their sensitivity to this surfactin is differentiated and depends on the microorganism species. In our studies, we found that the selected strains of bacteria and fungi were insensitive to this surfactin at a wide range of concentrations

Molecular evolution of enolase �

Enolase (EC 4.2.1.11) is an enzyme of the glycolytic pathway catalyzing the dehydratation reaction of 2-phosphoglycerate. In vertebrates the enzyme exists in three isoforms: α, β and γ. The amino-acid and nucleotide sequences deposited in the GenBank and SwissProt databases were subjected to analysis using the following bioinformatic programs: ClustalX, GeneDoc, MEGA2 and S.I.F.T. (sort intolerant from tolerant). Phylogenetic trees of enolases created with the use of the MEGA2 program show evolutionary relationships and functional diversity of the three isoforms of enolase in vertebrates. On the basis of calculations and the phylogenetic trees it can be concluded that vertebrate enolase has evolved according to the “birth and death ” model of evolution. An analysis of amino acid sequences of enolases: non-neuronal (NNE), neuron specific (NSE) and muscle specific (MSE) using the S.I.F.T. program indicated non-uniform number of possible substitutions. Tolerated substitutions occur most frequently in α-enolase, while the lowest number of substitutions has accumulated in γ-enolase, which may suggest that it is the most recently evolved isoenzyme of enolase in vertebrates

Role of Advanced Glycation End-Products and Other Ligands for AGE Receptors in Thyroid Cancer Progression

To date, thyroid cancers (TCs) remain a clinical challenge owing to their heterogeneous nature. The etiopathology of TCs is associated not only with genetic mutations or chromosomal rearrangements, but also non-genetic factors, such as oxidative-, nitrosative-, and carbonyl stress-related alterations in tumor environment. These factors, through leading to the activation of intracellular signaling pathways, induce tumor tissue proliferation. Interestingly, the incidence of TCs is often coexistent with various simultaneous mutations. Advanced glycation end-products (AGEs), their precursors and receptors (RAGEs), and other ligands for RAGEs are reported to have significant influence on carcinogenesis and TCs progression, inducing gene mutations, disturbances in histone methylation, and disorders in important carcinogenesis-related pathways, such as PI3K/AKT/NF-kB, p21/MEK/MPAK, or JAK/STAT, RAS/ERK/p53, which induce synthesis of interleukins, growth factors, and cytokines, thus influencing metastasis, angiogenesis, and cancer proliferation. Precursors of AGE (such as methylglyoxal (MG)) and selected ligands for RAGEs: AS1004, AS1008, and HMGB1 may, in the future, become potential targets for TCs treatment, as low MG concentration is associated with less aggressive anaplastic thyroid cancer, whereas the administration of anti-RAGE antibodies inhibits the progression of papillary thyroid cancer and anaplastic thyroid cancer. This review is aimed at collecting the information on the role of compounds, engaged in glycation process, in the pathogenesis of TCs. Moreover, the utility of these compounds in the diagnosis and treatment of TCs is thoroughly discussed. Understanding the mechanism of action of these compounds on TCs pathogenesis and progression may potentially be the grounds for the development of new treatment strategies, aiming at quality-of-life improvements

Paraoxonase (PON)-1 activity in overweight and obese children and adolescents: association with obesity-related inflammation and oxidative stress

Paraoxonase-1 (PON1) is a HDL-attached extracellular esterase which is believed to contribute to the anti-atherogenic and anti-inflammatory properties of HDL. A decrease in PON1 is a risk factor for cardiovascular disease and has recently been found to be associated with juvenile obesity. The issue of a possible association between enzyme activity and/or its phenotype distribution and obesity-related metabolic abnormalities, inflammation, and oxidative stress has not been addressed yet. To evaluate PON1 activity and phenotype distribution with respect to obesity and obesity-related metabolic disorders, inflammation and oxidative stress in children and adolescents. PON1 arylesterase activity was measured spectrophotometrically in 156 children and adolescents (47 lean, 27 overweight and 82 obese). Enzyme phenotype was determined using dual substrate (phenyl acetate/paraoxon) method. PON1 activity and phenotype distribution were related to the presence of obesity, metabolic syndrome, insulin resistance, hyperinsulinemia, hypertriglyceridemia, high blood pressure, low HDL level, impaired fasting glucose and/or glucose tolerance as well as inflammatory and oxidative stress indices. PON1 arylesterase activity decreased in general and central obesity, high blood pressure, and hyperinsulinemia conditions and correlated with BMI, CRP, adipocyte fatty acid-binding protein, superoxide dismutase, catalase, glutathione peroxidase, free thiols, and HOMA in a gender-dependent manner. PON1 decreases were independently associated with central obesity in girls, explaining 17% in PON1 variability, and with elevated CRP in boys, explaining 12% in its variability. PON1 phenotype was not associated with frequency of metabolic abnormalities. PON1 decreases in central obesity, exacerbating obesity-related inflammation and oxidative stress. The enzyme associations are gender-dependent: obesity and oxidative stress affects PON1 in girls whereas inflammation in boy