Enzymatic and molecular characterization of an endo-1,3-β-d-glucanase from the crystalline styles of the mussel Perna viridis

The retaining endo-1,3-β-d-glucanase (EC 3.2.1.39) was isolated from the crystalline styles of the commercially available Vietnamese edible mussel Perna viridis. It catalyzes hydrolysis of β-1,3-bonds in glucans and enables to catalyze a transglycosylation reaction. Resources of mass-spectrometry for analysis of enzymatic products were studied. cDNA sequence of endo-1,3-β-d-glucanase was determined by RT-PCR in conjunction with the rapid amplification of cDNA ends (RACE) methods. The cDNA of 1380 bp contains an open reading frame of 1332 bp encoding a mature protein of 328 amino acids. On basis of amino acid sequence analysis endo-1,3-β-d-glucanase was classified as a glycoside hydrolase of family 16.     

Polymorphism of yellow locus in Drosophila melanogaster from natural populations

We studied molecular characteristics of yellow (y; 1-0.0) locus, which determines the body coloration of phenotypically wild-type and mutant alleles isolated from geographically distant populations of Drosophila melanogaster in different years. According to Southern data, restrictions map of yellow locus of all studied strains differ from each other as well as from that of Oregon stock. FISH analysis shows that in the neighborhood of yellow locus in X chromosome neither P nor hobo elements are found in y1-775 stock, while only hobo is found there in y1-859 and y1-866 stocks, only P element in y+sn849 stock, and both elements in y1-719 stock. Thus, all studied mutant variants of yellow are of independent origin. Yellow locus residing at the very end of X chromosome (region 1A5-8 of cytologic map) carries significantly more transposon than retrotransposon-induced mutations, as compared to white locus (regions 3C2). It is possible that transposons are more active than retrotransposons at the chromosomal ends of D. melanogaster.     

Plasma and saliva miR-21 expression in colorectal cancer patients

MicroRNA-21 (miR-21) expression was quantified by real-time qRT-PCR in peripheral blood and saliva samples obtained from patients diagnosed with colorectal cancer (CRC) of varying degrees of malignancy and healthy volunteers. All patients had adenocarcinoma located in the distal colon at different stages. Significant differences were detected between the control group and the total experimental group of CRC patients (plasma, P?=?0.0001; saliva, P?=?5e-12). MiR-21 expression was also significantly different in certain subgroups of patients with CRC disease stages II–IV as compared to the control group. No correlation of miR-21 expression was found with regard to gender and age of patents. Also, there were no significant individual correlations and linear regression of miR-21 expression in the plasma and saliva. The estimated diagnostic sensitivity and specificity of miR-21 expression were respectively 65 and 85% in the plasma, and 97 and 91% in the saliva. Our data suggest that miR-21 in both the saliva and plasma could be a proper biomarker for CRC screening, although the saliva miR-21 expression test looks preferable due to its higher sensitivity, specificity, and technical simplicity.     

Activity of Embryonic Mink Genome during Diapause (Cytogenetic Analysis): Nucleolar and Extranucleolar RNA Synthesis

The nucleolar and extranucleolar RNA synthesis was studied in the mink blastocysts at different stages of embryonic diapause and during the periimplantation period using cytoradioautography. The data obtained suggest a differential and stage specific activity of the embryonic mRNA and rRNA synthesis during the period of delayed implantation.     

Acid-base status of the blood and adenine nucleotide metabolism in ruminant erythrocytes during early post-natal development]

It has been established that data of acid-base balance in cows' and newborn calves' blood closely correlate with physiological status of animals during their initial days of postnatal ontogenesis and depend on the peculiarities of metabolism in fetus and newborn organisms. Data on the acid-base balance in blood of newborn calves under diarrhea syndrome are discussed from the point of view of the influence of rehydration therapy and "Namacit" preparation on clinical status of animals.     

Mechanism of plasmid ColEl and pMB-9 mobilization by plasmid F'lac+ in Escherichia coli K-12]

The genetic control and mechanism of mobilization of the non-conjugative plasmids ColE1 and pMB-9 by the conjugative plasmids was orived to be recA-independent process in contrast to the mobilization of the chromosomal marker pro. Acridine orange and ethidium bromide curing data together with the results of electrophoretic analysis of plasmid DNA suggest that the plasmids F' lac+ and pMB-9 as well as F' lac+ and ColE1 remain autonomous after their contransfer to recipient cells. These data argue in favour of non-recombinational nature of the plasmid mobilization process. The possibility of transmission of a non-conjugative plasmid without transmission of a conjugative one from the donor strain carrying both plasmids was established. The results obtained are discussed with respect to the hypothesis on the effect of diffusible products encoded by the conjugative plasmid and required of the mobilization of the non-conjugative plasmid.     

DNA Repair Enzymes as Promising Targets in Oncotherapy

DNA repair is a complicated process that occurs due to a network of different pathways and mechanisms for correction of DNA damages during the normal DNA biosynthesis and under the influence of external and internal factors. The study of these mechanisms and their regulation is closely related to both diagnostics and the search for ways of treating various diseases, including oncological ones. Malignant neoplasms are one of the three most widespread diseases in the world, which unfortunately often become the reason for a lethal outcome. Traditional cancer therapy aims to the DNA damage in malignant cells, and its result depends on the efficiency of the repair systems. In many cancer cells, the individual DNA repair enzymes are overexpressed, which promotes the resistance of these tumors to the therapy. On the other hand, defects in the DNA repair systems in cancer cells allow researchers to find both appropriate biomarkers for diagnostics and targets for the development of the specific and effective therapy. Currently, DNA repair inhibitors are being actively developed in order to increase the sensitivity of the tumor cells to traditional chemotherapy. The principle of synthetic lethality is used to create cell-specific drugs and to improve the effectiveness of the treatment. In this review, we discuss the current state of research and prospects for the development of inhibitors for five important DNA repair enzymes.     

Characteristics of the electrolyte balance of the blood of healthy newborn calves and calves with diarrhea

Cows and newborn (just after the birth, and on the 1st, 3rd, 5th and 10th days after it) calves were tested for the peculiarities of the electrolyte blood composition and acid-base balance under normal and diarrheic conditions. The values of Na+/K+, Cl-/HCO3-, Pn/Ca2+ ratios in the blood serum of sick animals remain unchanged, which testifies to the deep disturbances of the water-salt metabolism in tissues.     

Catalytic properties of endo-1,3-β-D-glucanase from the Vietnamese edible mussel Perna viridis

A β-1,3-glucanase with a molecular mass of 33 kDa was isolated in the homogeneous state from a crystalline stalk of the commercially available Vietnamese edible mussel Perna viridis. It hydrolyzes β-1,3-bonds in glucans and is capable of catalyzing the transglycosylation reaction. The β-1,3-glucanase has a K _m value of 0.3 mg/ml for the hydrolysis of laminaran and shows a maximum activity in the pH range from 4 to 6.5 and at 45°C. Its half-inactivation time is 180 min at 45°C and 20 min at 50°C. The enzyme was ascribed to glucan-endo-(1 → 3)-β-D-glucosidases (EC 3.2.1.39). The enzyme could be used in the structure determination of β-1,3-glucans and enzymatic synthesis of new carbohydrate-containing compounds.