Figure 6
From: Discovery of anaerobic lithoheterotrophic haloarchaea, ubiquitous in hypersaline habitats
Summary of C1 metabolism in Halodesulfurarchaeum formicicum HTSR1 representing ancestral routes of glycine, serine and methyl group chemistry (Braakman and Smith, 2012). Pathways shown in the model were deduced on the basis of genome annotation and genome-wide proteomic analysis of cells grown on different electron acceptors. Enzymes involved: (1) formate transporter (HTSR_0446) or formate/oxalate antiporter (HTSR_1713); (1 A) numerous amino acid permeases; (2) formate dehydrogenase subunit alpha (HTSR_1736 [A], 1740 [B]); (3) formate—tetrahydrofolate ligase (HTSR_1739); (4) 5,10-methylenetetrahydrofolate reductase (HTSR_1746); (5) methylenetetrahydrofolate dehydrogenase (NADP+) (HTSR_1747); (6) serine hydroxymethyltransferase (HTSR_0671); (7) glycine cleavage system proteins H, P and T (HTSR_0503-0506, 1750); (8) methylenetetrahydrofolate reductase (NADPH) (HTSR_1220); (9) electron transfer flavoprotein (HTSR_1748-1749); (10) methionine synthase (HTSR_1805); (11) S-adenosylmethionine hydroxide adenosyltransferase (HTSR_1447); (12) S-adenosylmethionine-dependent methyltransferase (HTSR_1450); (13) adenosylhomocysteinase (HTSR_0160); (14) D-3-phosphoglycerate dehydrogenase (HTSR_0539), (15) phosphoserine phosphatase (HTSR_1388). The data for the 150 most abundant proteins from proteomic analysis are outlined in the small nested box. The proteins are sorted according to their relative abundance in cells grown on formate+thiosulfate. Proteins involved in C1 metabolism are indicated in red. Abbreviations: Fd, ferrodoxin; THF, tetrahydrofolate.
