The unicellular green microalga is a powerful photosynthetic model organism which is capable of heterotrophic growth on acetate as a sole carbon source. This capacity has enabled its use for investigations of perturbations in photosynthetic machinery as mutants can be recovered heterotrophically. Fixation of acetate into cellular carbon metabolism occurs first by its conversion into acetyl-CoA by a respective synthase and the generation of succinate by the glyoxylate cycle.
View Article and Find Full Text PDFCationic antimicrobial peptides (CAMPs) are essential components of innate immunity. Here we show that antimicrobial potency of CAMPs is linearly correlated to the product CHL where C is the net charge of the peptide, H is a measure of its hydrophobicity and L its length. Exponents m and n define the relative contribution of charge and hydrophobicity to the antimicrobial potency.
View Article and Find Full Text PDFCommercial uses of bioactive peptides require low cost, effective methods for their production. We developed a new carrier protein for high yield production of recombinant peptides in Escherichia coli very well suited for the production of toxic peptides like antimicrobial peptides. GKY20, a short antimicrobial peptide derived from the C-terminus of human thrombin, was fused to the C-terminus of Onconase, a small ribonuclease (104 amino acids), which efficiently drove the peptide into inclusion bodies with very high expression levels (about 200-250 mg/L).
View Article and Find Full Text PDFIn anaerobiosis, the microalga Chlamydomonas reinhardtii is able to produce H2 gas. Electrons mainly derive from mobilization of internal reserves or from water through biophotolysis. However, the exact mechanisms triggering this process are still unclear.
View Article and Find Full Text PDFBackground: Novosphingobium sp. strain PP1Y is a marine α-proteobacterium adapted to grow at the water/fuel oil interface. It exploits the aromatic fraction of fuel oils as a carbon and energy source.
View Article and Find Full Text PDFCold-adapted enzymes possess high specific activity at low and moderate temperatures with respect to their mesophilic and thermophilic homologs; it is accepted that they have a less rigid and more flexible structure in the region surrounding the active site. However, the low stability of such molecules could represent the main barrier for their application in some industrial bioprocesses. The aim of this article was to investigate the ability of the naturally occurring osmolytes to increase the thermal stability and the specific activity of the cold-active lipase from Psychrobacter sp.
View Article and Find Full Text PDFVitis vinifera cell suspensions are a suitable system to study the metabolic regulation of a large range of polyphenols, including flavonoids and stilbenes that play important roles in plant development. Grape cv. Barbera petioles cell cultures were treated with red light and 10 μM methyl-jasmonate (MeJA), alone or in combination, to investigate their influence and/or induction effect on the production of anthocyanins, catechins and free and mono-glucosylated stilbenes.
View Article and Find Full Text PDFThe multiple antibiotic resistance regulators (MarR) constitute a family of ligand-responsive transcriptional regulators abundantly distributed throughout the bacterial and archaeal domains. Here we describe the identification and characterization of BldR2, as a new member of this family, in the archaeon Sulfolobus solfataricus and report physiological, biochemical, and biophysical investigation of its stability and DNA binding ability. Transcriptional analysis revealed the upregulation of BldR2 expression by aromatic compounds in the late-logarithmic growth phase and allowed the identification of cis-acting sequences.
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