Simplified carbon metabolic network. Identified enzymes from pathways involved in glycerol and methanol metabolism, from the glycolytic and pentose phosphate pathway, and TCA cycle and their changes in response to the shift from growth on glycerol to growth and HBsAg production on methanol. The red arrow (↑) indicates an increasing and the green arrow (↓) a decreasing amount of the enzyme in the methanol fed-batch phase. An orange dash (−) indicates no significant change. One arrow indicates small (0.6-1 log2 change), two arrows strong (1–4 log2 change) and three arrows very strong changes (> 4 log2 change). Abbreviations (enzymes): AOX1, alcohol oxidase 1; CTA1, catalase; PMP20, peroxiredoxin; FLD1, formaldehyde dehydrogenase; FGH1, S-formylglutathione hydrolase; FDH1, NAD(+)-dependent formate dehydrogenase; ADH, alcohol dehydrogenase; DAS1, transketolase (dihydroxyacetone synthase); TPI1, triose phosphate isomerase; FBA1, fructose 1,6-bisphosphate aldolase; TDH1, glyceraldehyde-3-phosphate dehydrogenase; PGK1, 3-phosphoglycerate kinase; GMP1, tetrameric phosphoglycerate mutase; ENO2, enolase; 6PGD, 6-phosphogluconate dehydrogenase; RKI1, 1-ribose-5-phosphate ketol-isomerase; ACO1, aconitase; IDH2, subunit of mitochondrial NAD(+)-dependent isocitrate dehydrogenase; FUM1, fumarase; MDH1, mitochondrial malate dehydrogenase.