Search results for "Enzymatic synthesis"
showing 4 items of 4 documents
Comparative biochemistry of CO2 fixation and the evolution of autotrophy
1999
Carbon dioxide fixation is a polyphyletic trait that has evolved in widely separated prokaryotic branches. The three principal CO2-assimilation pathways are (i) the reductive pentose-phosphate cycle, i. e. the Calvin-Benson cycle; (ii) the reductive citric acid (or Arnon) cycle; and (iii) the net synthesis of acetyl-CoA from CO/CO2, or Wood pathway. Sequence analysis and the comparative biochemistry of these routes suggest that all of them were shaped to a considerable extent by the evolutionary recruitment of enzymes. Molecular phylogenetic trees show that the Calvin-Benson cycle was a relatively late development in the (eu)bacterial branch, suggesting that some form(s) of carbon assimilat…
Silicateins - A Novel Paradigm in Bioinorganic Chemistry: Enzymatic Synthesis of Inorganic Polymeric Silica
2013
The inorganic matrix of the siliceous skeletal elements of sponges, that is, spicules, is formed of amorphous biosilica. Until a decade ago, it remained unclear how the hard biosilica monoliths of the spicules are formed in sponges that live in a silica-poor (<50 mu m) aquatic environment. The following two discoveries caused a paradigm shift and allowed an elucidation of the processes underlying spicule formation; first the discovery that in the spicules only one major protein, silicatein, exists and second, that this protein displays a bio-catalytical, enzymatic function. These findings caused a paradigm shift, since silicatein is the first enzyme that catalyzes the formation of an inorga…
Chemical and enzymatic synthesis of glycopeptides
1995
Progress recently made in the synthesis of biologically relevant N- and O-glycopeptides is illustrated by examples. In this context, developments in the preparation of complex saccharide side chains and in the subsequent coupling to peptide portions is described. Special emphasis is given to the synthesis of Lewis antigen-type structures. Furthermore, modern methods in solid phase peptide syntheses utilizing glycosylated building blocks are presented. Recent advances in glycopeptide syntheses employing enzymatic methods in deprotection steps as well as in peptide/saccharide chain elongation are reported.