Methanol utilization (MUT) pathway in P. pastoris. A, MUT pathway overview (adapted from [5] and [16]); B, catalytic reaction of DAS1, DAS2 and hypothetically TKL1; C, catalytic reaction of FLD1; D, catalytic reaction of TKL1 in the pentose phosphate pathway. ADH: methylformate synthase. AOX: alcohol oxidase. CAT: catalase. DAK: dihydroxyacetone kinase. DHA: dihydroxyacetone. DHAP: dihydroxyacetone phosphate. F1,6BP: fructose-1,6-bisphosphate. F6P: fructose-6-phosphate. FBA: fructose-1,6-bisphosphate aldolase. FBP: fructose-1,6-bisphosphatase. FLD: formaldehyde dehydrogenase. FDH: formate dehydrogenase. FGH: S-formylglutathione hydrolase. GAP: glyceraldehyde-3-phosphate. GSH: glutathione. Pyr: pyruvate. PPP: pentose phosphate pathway. Ri5P: ribose-5-phosphate. SeHe7P: sedoheptulose-7-phosphate. TCA: tricarboxylic acid cycle. Xu5P: xylulose-5-phosphate.