The Assimilation of 1-C compounds

Formate as the Main Branch Point for Methylotrophic Metabolism in Methylobacterium extorquens AM1

“…A revised kinetic model was used to validate this possibility, showing that physiologically plausible parameters in this model can account for the metabolic fluxes observed in vivo. These results all support the suggestion that formate, not formaldehyde, is the main branch point for methylotrophic metabolism in M. extorquens AM1.Methylobacterium extorquens AM1 is a facultative methylotroph that has served as a model system for understanding methylotrophic metabolism for many decades (1,3,33). One outstanding question in methylotrophic metabolism involves the route by which C 1 compounds are incorporated into assimilatory metabolism.…”

“…Methylobacterium extorquens AM1 is a facultative methylotroph that has served as a model system for understanding methylotrophic metabolism for many decades (1,3,33). One outstanding question in methylotrophic metabolism involves the route by which C 1 compounds are incorporated into assimilatory metabolism.…”

“…In this bacterium, methanol or methylamine is oxidized via formaldehyde and formate to CO 2 for energy metabolism and carbon is assimilated via the serine cycle ( Fig. 1) (1,3,33). The entry point into the serine cycle is methylene tetrahydrofolate (H 4 F).…”

Methanotrophic bacteria.

“…Formate is oxidized to carbon dioxide by an NAD-dependent formate dehydrogenase in most if not all methanotrophs (22,112). A cyclic pathway for the oxidation of formaldehyde to carbon dioxide has been described and found to exist in methylotrophs that possess the RuMP pathway for formaldehyde assimilation (22,308,309,372,431). In this pathway, formaldehyde and ribulose-5-phosphate react to form hexulose-6-phosphate, which is isomerized to fructose-6-phosphate, and this substrate is converted to glucose-6-phosphate, which is in turn oxidized to 6-phosphogluconate.…”

John Rodney Quayle (1926–2006), a Brilliant Scientist Who was Also a Wise and Innovative Academic Administrator

“…In addition to his election as a Fellow of the Royal Society, he was awarded Honorary Doctorates from the universities of Gö ttingen, Bath, and Sheffield; elected to Corresponding Membership of the Academy of Sciences of Gö ttingen; and awarded the CIBA Medal and Prize of The Biochemical Society (Quayle 1980). But, perhaps, his greatest memorial is the affection in which he is held by his many students and colleagues-he was a warm, witty, and wise man, and he will be much missed.…”