Tetrahydromethanopterin, a coenzyme involved in autotrophic acetyl coenzyme A synthesis from 2 CO₂ in <i>Methanobacterium</i>

Abstract

Methanobacterium thermoautotrophicum , a methane forming archaebacterium, grows autotrophically by synthesizing activated acetic acid from 2 CO 2 . It is demonstrated in vitro that the methyl group of acetate is derived from methenyl tetrahydromethanopterin, which is known to be a one‐carbon carrying coenzyme in CO 2 reduction to methane. The direct acetate precursors are suggested to be methyl tetrahydromethanopterin (“activated methanol”) and “activated carbon monoxide”.