Figure 2

Metabolic network of xylose and maltose catabolism. Simplified scheme of the extra- and intracellular pathways involved in xylose and maltose catabolism in A. niger [64]. The reaction numbers correspond to reactions listed in Additional file 1. Proteins identified from 2-D gels (indicated by gray background) include enzymes from the glycolytic pathway: 4 (fructose-bis-phosphate aldolase, An02g07470); 5 (triose phosphate isomerase, An14g04920); 6 (glyceraldehde-3-phosphate dehydrogenase, An16g01830); 7 (phosphoglycerate kinase, An08g02260); 9 (enolase, An18g06250); 11 (pyruvate dehydrogenase complex: pyruvate dehydrogenase E1, An07g09530, dihydrolipoamide dehydrogenase E3, An07g06840); TCA cycle enzymes: 13 (aconitase, An08g10530); 15 (α-ketoglutarate dehydrogenas complex: dihydrolipoamide dehydrogenase E3, An07g06840); 18 m (fumarase, An12g07850); 19 m (malate dehydrogenase, An07g02160, An15g00070); enzymes from the pentose phosphate pathway: 24 (ribose-5-phosphate isomerase, An02g02930); 26 (transaldolase, An07g03850); enzymes from the malate-aspartate shuttle: 52 m (aspartate aminotransferase, An04g06380); enzymes involved in anaerobic redox balancing: 17c (cytoplasmic fumarate reductase, An06g00990); enzymes involved in polyol metabolism: 30 (sorbitol dehydrogenase, An01g03480); acetate formation (acetyl-CoA hydrolase, An16g07110); xylose breakdown: 48 (xylose reductase, An01g03740); and the enzymes involved in the extracellular maltose and glucose breakdown: 28 (glucoamylase An03g06550; α-amylase, An11g03340), 39 (glucose oxidase, An01g14740) and 40 (catalase, An01g01550).