Non-enzymatic acetylation inhibits glycolytic enzymes in Escherichia coli.

Advanced mass spectrometry methods have detected thousands of post-translational phosphorylation and acetylation sites in bacteria, but their functional role and the enzymes catalyzing these modifications remain largely unknown. In addition to enzymatic acetylation, lysine residues can also be chemically acetylated by the metabolite acetyl phosphate. In Escherichia coli, acetylation at over 3,000 sites has been linked to acetyl phosphate, but the functionality of this widespread non-enzymatic acetylation is even less clear than the enzyme-catalyzed one.

Extensive regulation of enzyme activity by phosphorylation in Escherichia coli.

Protein serine/threonine/tyrosine (S/T/Y) phosphorylation is an essential and frequent post-translational modification in eukaryotes, but historically has been considered less prevalent in bacteria because fewer proteins were found to be phosphorylated and most proteins were modified to a lower degree. Recent proteomics studies greatly expanded the phosphoproteome of Escherichia coli to more than 2000 phosphorylation sites (phosphosites), yet mechanisms of action were proposed for only six phosphosites and fitness effects were described for 38 phosphosites upon perturbation. By systematically characterizing functional relevance of S/T/Y phosphorylation in E.

Non-photochemical quenching in the cells of the carotenogenic chlorophyte Haematococcus lacustris under favorable conditions and under stress.

The microalga Haematococcus lacustris (formerly H. pluvialis) is the richest source of the valuable pigment astaxanthin, accumulated in red aplanospores (haematocysts). In this work, we report on the photoprotective mechanisms in H.

Effects of CO enrichment on primary photochemistry, growth and astaxanthin accumulation in the chlorophyte Haematococcus pluvialis.

The atmospheric CO level is limiting for growth of phototrophic organisms such as microalgae, so CO enrichment boosts the growth and photosynthesis of microalgal cultures. Still, excessive CO injection might inhibit photosynthesis of microalgae. We investigated the effect of continuous sparging of the cultures of Haematococcus pluvialis BM 1 (IPPAS H-2018) (Chlorophyceae), the richest natural source of the value-added pigment astaxanthin.