Search results for "Transferases"
showing 10 items of 426 documents
Enhanced Accumulation of Betulinic Acid in Transgenic Hairy Roots of Senna obtusifolia Growing in the Sprinkle Bioreactor and Evaluation of Their Bio…
2021
Betulinic acid, which is found in transgenic roots of Senna obtusifolia (L.) H.S.Irwin & Barneby, is a pentacyclic triterpene with distinctive pharmacological activities. In this study, we report the differences in the content of betulinic acid and selected anthraquinones in transgenic S. obtusifolia hairy roots with overexpression of the PgSS1 gene (SOPSS2 line) and in transformed hairy roots without this genetic construct (SOA41 line). Both hairy root lines grew in 10 L sprinkle bioreactor. Additionally, the extracts obtained from this plant material were used for biological tests. Our results demonstrated that the SOPSS2 hairy root cultures from the bioreactor showed an increase in the c…
Inhibition of FcεRI-mediated Activation of Rat Basophilic Leukemia Cells by Clostridium difficile Toxin B (Monoglucosyltransferase)
1996
Abstract Treatment of rat basophilic leukemia (RBL) 2H3-hm1 cells with Clostridium difficile toxin B (2 ng/ml), which reportedly depolymerizes the actin cytoskeleton, blocked [3H]serotonin release induced by 2,4-dinitrophenyl-bovine serum albumin, carbachol, mastoparan, and reduced ionophore A23187-stimulated degranulation by about 55-60%. In lysates of RBL cells, toxin B 14C-glucosylated two major and one minor protein. By using two-dimensional gel electrophoresis and immunoblotting, RhoA and Cdc42 were identified as protein substrates of toxin B. In contrast to toxin B, Clostridium botulinum transferase C3 that selectively inactivates RhoA by ADP-ribosylation did not inhibit degranulation…
Thymidine-, uridine- and choline-kinase in rabbit kidney cells infected with herpesvirus hominis, type I and II.
1972
Data are presented about the activity of the thymidine-, uridine- and choline-kinase after infection with 21 strains ofherpesvirus hominis of serotype I or II in rabbit kidney cells. Type I strains increase the activity of the thymidine-kinase 15–20 fold over the controls, whereas the type II strains demonstrate a moderate activity, the level of the enzyme is increased 2–5 fold. One giant cell forming strain exhibits unusual properties, the TK activity decreases in correlation to the controls. The uridine- and choline-kinases induce the respective enzymes in different manner. The strains tested are divided into 5 groups depending upon the activity of the enzymatic activity. The implications…
Induction capacity and influence of dThdMP on thymidine kinase activity of type 1 and 2 strains of herpes simplex virus
1978
The thymidine kinase inducing ability of 104 strains of herpes simplex virus was studied comparatively. A pronounced relationship was established between induction of the enzyme and the serotype of the strains. As a rule, the strains of serotype 2 are weaker inducer of dThd- and dCyd-kinase activity than serotype 1 strains. A certain parallelism exists between induction of both enzymes, however the activity of the thymidine kinase increases after infection with herpes simplex virus 4--5 times more than that of the dCyd-kinase. Adaptation of the strains to cell cultures only slightly modifies the inducing ability of the herpes simplex virus strains. The thymidine kinase activity induced by H…
Evolution and functional differentiation of recently diverged phytochelatin synthase genes from Arundo donax L.
2019
Plant phytochelatin synthases undergo evolutionarily rapid functional differentiation after duplication, allowing fast and precise adjustment of metal detoxification capacity by modulation of both transcription and enzymatic activity.
dfh is a Drosophila homolog of the Friedreich's ataxia disease gene
2000
Abstract A putative Drosophila homolog of the Friedreich's ataxia disease gene (FRDA) has been cloned and characterized; it has been named Drosophila frataxin homolog (dfh). It is located at 8C/D position on X chromosome and is spread over 1 kb, a much smaller genomic region than the human gene. Its genomic organization is simple, with a single intron dividing the coding region into two exons. The predicted encoded product has 190 amino acids, being considered a frataxin-like protein on the basis of the sequence and secondary structure conservation when compared with human frataxin and related proteins from other eukaryotes. The closest match between the Drosophila and the human proteins in…
Aberrant methylation of tRNAs links cellular stress to neuro-developmental disorders.
2014
Mutations in the cytosine-5 RNA methyltransferase NSun2 cause microcephaly and other neurological abnormalities in mice and human. How post-transcriptional methylation contributes to the human disease is currently unknown. By comparing gene expression data with global cytosine-5 RNA methylomes in patient fibroblasts and NSun2-deficient mice, we find that loss of cytosine-5 RNA methylation increases the angiogenin-mediated endonucleolytic cleavage of transfer RNAs (tRNA) leading to an accumulation of 5' tRNA-derived small RNA fragments. Accumulation of 5' tRNA fragments in the absence of NSun2 reduces protein translation rates and activates stress pathways leading to reduced cell siz…
Role of secondary transporters and phosphotransferase systems in glucose transport by Oenococcus oeni.
2011
ABSTRACT Glucose uptake by the heterofermentative lactic acid bacterium Oenococcus oeni B1 was studied at the physiological and gene expression levels. Glucose- or fructose-grown bacteria catalyzed uptake of [ 14 C]glucose over a pH range from pH 4 to 9, with maxima at pHs 5.5 and 7. Uptake occurred in two-step kinetics in a high- and low-affinity reaction. The high-affinity uptake followed Michaelis-Menten kinetics and required energization. It accumulated the radioactivity of glucose by a factor of 55 within the bacteria. A large portion (about 80%) of the uptake of glucose was inhibited by protonophores and ionophores. Uptake of the glucose at neutral pH was not sensitive to degradation …
Levansucrases from Pseudomonas syringae pv. tomato and P. chlororaphis subsp. aurantiaca: Substrate specificity, polymerizing properties and usage of…
2011
Levansucrases of Pseudomonas syringae pv. tomato DC3000 (Lsc3) and Pseudomonas chlororaphis subsp. aurantiaca (also Pseudomonas aurantiaca) (LscA) have 73% identity of protein sequences, similar substrate specificity and kinetic properties. Both enzymes produce levan and fructooligosaccharides (FOS) of varied length from sucrose, raffinose and sugar beet molasses. A novel high-throughput chip-based nanoelectrospray mass spectrometric method was applied to screen alternative fructosyl acceptors for levansucrases. Lsc3 and LscA could both transfructosylate D-xylose, D-fucose, L- and D-arabinose, D-ribose, D-sorbitol, xylitol, xylobiose, D-mannitol, D-galacturonic acid and methyl-α-D-glucopyra…
Pyrrolomycins as antimicrobial agents. Microwave-assisted organic synthesis and insights into their antimicrobial mechanism of action
2019
Abstract New compounds able to counteract staphylococcal biofilm formation are needed. In this study we investigate the mechanism of action of pyrrolomycins, whose potential as antimicrobial agents has been demonstrated. We performed a new efficient and easy method to use microwave organic synthesis suitable for obtaining pyrrolomycins in good yields and in suitable amount for their in vitro in-depth investigation. We evaluate the inhibitory activity towards Sortase A (SrtA), a transpeptidase responsible for covalent anchoring in Gram-positive peptidoglycan of many surface proteins involved in adhesion and in biofilm formation. All compounds show a good inhibitory activity toward SrtA, havi…