Search results for " Biosynthesis"

Biotechnological Approaches to Increase Essential Oil Yield and Quality in Aromatic Plants: The Lavandula latifolia (Spike Lavender) Example. Past an…

2019

Increasing knowledge about isoprenoid biosynthesis pathways has provided new tools for aromatic plant breeding using biotechnological approaches. Notably, there are possibilities to modify essential oil profiles and enhance production of valuable monoterpenes. This attains a particular significance in Lavandula latifolia Medik. (spike lavender), one of the most important essential oil crops in Spain. This chapter summarizes work done to improve essential oil yield and quality by engineering: (1) the enzymes controlling regulatory steps of methyl-D-erythritol 4-phosphate (MEP) and mevalonic acid (MVA) pathways to increase C5 units employed for monoterpene biosynthesis and (2) the monoterpene…

Cloning of branched chain amino acid biosynthesis genes and assays of alpha-acetolactate synthase activities in Leuconostoc mesenteroides subsp. crem…

1999

A genomic library from Leuconostoc mesenteroides subsp. cremoris (Lmc) in Escherichia coli was screened for alpha-acetolactate synthase (ALS) activity using a phenotypic test detecting the production of acetolactate or related C4 derivatives (diacetyl, acetoin or 2,3-butanediol) in the culture. Four recombinant E. coli clones, with plasmids containing overlapping DNA fragments and displaying anabolic ALS activity, were selected. This activity is encoded by an ilvB gene belonging to a putative operon which contains genes highly similar to the genes of the branched chain amino acid (BCAA) operon of Lactococcus lactis subsp. lactis. This putative BCAA operon is not functional as the ilvA gene …

Effects of some isoxazolpyrimidine derivatives on nitric oxide and eicosanoid biosynthesis

2000

Abstract The inhibitory effect of some isoxazolpyrimidine derivatives on iNOS and COX-2 endotoxin induction in mouse peritoneal macrophages has been studied. Three of these compounds inhibited nitrite and PGE2 accumulation in a concentration dependent-manner at μM range. None of these active compounds affected iNOS, COX-2, COX-1 or PLA2 activities, although some reduced iNOS or COX-2 expression. Besides, no effect was observed on human neutrophil inflammatory responses (LTB4 biosynthesis and Superoxide or elastase release). Active compounds were assayed by oral administration in the mouse air pouch model, where they inhibited nitrite accumulation without affecting PGE 2 levels or leukocyte …

Tetracycline inhibits the nitric oxide synthase activity induced by endotoxin in cultured murine macrophages

1998

Here we investigate the effects of tetracycline base and of a semi-synthetic tetracycline derivative, doxycycline, on the induction of inducible nitric oxide synthase and, hence, on the production of nitric oxide (NO) by lipopolysaccharide in J774 macrophage cultured in vitro. The treatment of J774 line with tetracycline base (6.25-250 microM) or doxycycline (5-50 microM) dose-dependently decreased the lipopolysaccharide-stimulated (1 microg/ml) inducible NO synthase activity and, consequently, nitrite formation. For instance, the inhibition was 70% for tetracycline base at 250 microM and 68% for doxycycline at 50 microM. The inhibitory effect of tetracyclines was due neither to a reduction…

Identification and characterization of a novel Ets-2-related nuclear complex implicated in the activation of the human interleukin-12 p40 gene promot…

1997

Interleukin-12 (IL-12) is a proinflammatory cytokine produced by antigen-presenting cells in response to many microbial infections. IL-12 plays an important role in the generation of T helper type-1 cells, which favor cell-mediated immune response. IL-12 is composed of two different subunits, p40 and p35, whose expression can be regulated concomitantly or differentially. Monocytic cells, the major producers of IL-12, can be primed by interferon-gamma (IFN-gamma) to produce optimal amounts of IL-12 in response to LPS stimulation as a consequence of bacterial infection. The priming effect is exerted primarily at the transcriptional level on the p40 promoter in conjunction with the effects of …

Tissue inhibitor of metalloproteinases-2 (TIMP-2) in rat liver cells is increased by lipopolysaccharide and prostaglandin E2

1995

AbstractTo explore the functional role of TIMP-2 in liver, we determined TIMP-2 mRNA levels in primary rat hepatocytes and in total rat liver. Rat hepatocytes constitutively express TIMP-2 mRNA at a low level. Incubation with dexamethasone, prostaglandin E2 and a combination of inflammatory cytokines leads to an up-regulation of TIMP-2 mRNA. In rats in vivo we found a dramatic increase of TIMP-2 expression after intraperitoneal injection of lipopolysaccharide. Compared to our previous findings on TIMP-1 we conclude that TIMP-2 mRNA expression is regulated in a distinct and partially opposite manner. Over-production of TIMP-2 could inhibit the activity of metalloproteinases and thus lead to …

Sex hormones modulate inflammatory mediators produced by macrophages.

1999

The stellate cell (Ito-cell, fat-storing cell, lipocyte, perisinusoidal cell) of the liver. New insights into pathophysiology of an intriguing cell.

1992

Identification and characterization of an ABA-activated MAP kinase cascade in Arabidopsis thaliana.

2015

†These authors contributed equally to the work. Accession numbers Sequence data from this article can be found in Arabidopsis Genome Initiative or GenBank/EMBL databases under the following accession numbers: At1g10210 (MPK1), At1g59580 (MPK2), At2g43790 (MPK6), At2g18170 (MPK7), At1g18150 (MPK8), At4g36450 (MPK14), At5g40440 (MKK3), At2g32510 (MAP3K17) and At1g05100 (MAP3K18). SUMMARY Abscisic acid (ABA) is a major phytohormone involved in important stress-related and developmental plant processes. Recent phosphoproteomic analyses revealed a large set of ABA-triggered phosphoproteins as putative mitogen-activated protein kinase (MAPK) targets, although the evidence for MAPKs involved in AB…

Construction of Chimeric Dual-Chain Avidin by Tandem Fusion of the Related Avidins

2011

BackgroundAvidin is a chicken egg-white protein with high affinity to vitamin H, also known as D-biotin. Many applications in life science research are based on this strong interaction. Avidin is a homotetrameric protein, which promotes its modification to symmetrical entities. Dual-chain avidin, a genetically engineered avidin form, has two circularly permuted chicken avidin monomers that are tandem-fused into one polypeptide chain. This form of avidin enables independent modification of the two domains, including the two biotin-binding pockets; however, decreased yields in protein production, compared to wt avidin, and complicated genetic manipulation of two highly similar DNA sequences i…